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Bringing Extinct Species Back to Life | Dr. Beth Shapiro

第301期2026-10-05English

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§01Transcript — part 1

00:00So our direwolves, they have 20 edits that we picked and we sequenced genomes from fossil

00:06direwolves. We learned from those genomes what genetic changes made those animals bigger,

00:12more robust, light colored in coat. And then we engineered those changes into a gray wolf genome

00:18to recreate the direwolf. You know, I often get the question of why are you thinking about bringing

00:22extinct species back to life? Why aren't you thinking about helping living species not become extinct?

00:30And the answer is, we are doing both.

00:31It is the same tools.

00:33It's the same technology.

00:35It's the same needs.

00:37And when we excite people with the idea of mammoths and dodos and thylacines,

00:43we get more engagement and enthusiasm and investment in developing the technology

00:48that we can use to stop living species from becoming extinct.

00:52Welcome to the Huberman Lab podcast,

00:54where we discuss science and science-based tools for everyday life.

01:01I'm Andrew Huberman, and I'm a professor of neurobiology and ophthalmology at Stanford

01:06School of Medicine.

01:07My guest today is Dr. Beth Shapiro.

01:10Dr. Beth Shapiro is an evolutionary biologist.

01:13She was a professor at UC Santa Cruz and an investigator with the Howard Hughes Medical

01:18Institute before leaving to become chief scientific officer at Colossal Biosciences.

01:23Her work at Colossal is focused on what is called de-extincting species such as the woolly

01:27mammoth, the dodo bird, and the dire wolf, meaning bringing them back to life. But that

01:32entire initiative is also about species preservation more broadly and how genomics can be used to

01:38improve the global ecosystem. In this episode, we discuss what it means to use ancient DNA

01:43to bring back extinct species, which then led us to a broader discussion about genetic

01:47engineering in human health, both of which, by the way, are happening right now. So this

01:52is not just a projection into what's coming in the future. As you'll see, Dr. Beth Shapiro

01:57a one-of-a-kind thinker.

01:59And today you'll learn the science,

02:00the ethical implications,

02:02and the positive potential of using genetics

02:04to de-extinct species and using genetic selection

02:07and genetic tools to change humans.

02:10And no, Dr. Beth Shapiro is not planning

02:12to bring back dinosaurs, and today you'll learn why.

02:16Before we begin, I'd like to emphasize

02:17that this podcast is separate from my teaching

02:19and research roles at Stanford.

02:21It is, however, part of my desire and effort

02:23to bring zero cost to consumer information

02:25about science and science-related tools

02:27public. In keeping with that theme, today's episode does include sponsors. And now for my

02:32discussion with Dr. Beth Shapiro. Dr. Beth Shapiro, welcome. Thank you. Long time fan of your work.

02:39Same. Love animals, love stories about animals that aren't around anymore. Heard that you're

02:45going to bring back the woolly mammoths, the dodo bird, and that you might have already done

02:48something to contribute to the proliferation of the black-footed ferret. I'm a big fan of

02:54mustelids of which ferrets are. We're going to talk about all of that today, including the

02:58ethical implications and so on. But I have a very basic question, which is how do you decide

03:05what a species is? Because you have a degree in zoology. I always wanted to get a degree in

03:10zoology. But a few years ago, we got this thing called DNA sequencing. We can look at ancient DNA,

03:16can look at skeletons. People have done that for a long time. And my understanding is that it's

03:21completely revised the understanding of the relationship between different animals and the

03:26number of branches in these phylogenetic trees. So what have we learned that I think people might

03:32appreciate understanding about taxonomy and like, is my dog as a bulldog mutt really the same as a

03:40chihuahua? Are they really the same species? Right. That's a really fascinating way to put it.

03:45And I think the most important thing that most people probably don't think about is that

03:51Biology doesn't care what species you are. Species is a human concept. We have this incredible

03:59proclivity to want to put things into boxes so that we can talk about them, so that we can have

04:05conversations or share stories or share memories. In order to share something, we have to know what

04:10to call it. That's one of the reasons language has been so fundamental to the evolution of our

04:15species and our social structures. So what is a species? Probably when you learned about species

04:21biology class when you were in middle school. You learned about Ernst Mayr's biological species

04:26concept. Kingdom, phylum, order, genus, species, like this kind of thing, clade, you know?

04:31That's the taxonomy, right? So we have Linnaeus came up with this idea of doing taxonomy, right?

04:36So here's an interesting taxonomy story. I've spent a lot of my career working on bison for

04:42unfortunate reasons, probably, or fun reasons or whatever, but a lot of time working on bison.

04:46And bison were called buffalo, right?

04:50We think of American bison as buffalo.

04:52It's the same thing.

04:53It's the same thing.

04:53But bison is the taxonomic name that was given to American buffalo by Carl Linnaeus.

04:59Because when Europeans were going around the world and finding for the first time, Europeans had seen all these different animals.

05:06If they saw a big animal that looked like it would make a good coat, that was called a bouff coat.

05:13They called it a buffalo or a buffalo, right?

05:16So we have African buffalo and Asian buffalo and American buffalo, and they are not related to each other at all if you look at their DNA.

05:23But they all have the same name because they all made a good coat at some point, or at least there was the idea that they would.

05:30But taxonomists found this to be very disturbing.

05:35We want to know what animal we're talking about when we say the buffalo.

05:39And so this is why Carl Linnaeus comes up with this scheme.

05:43The American bison, the American buffalo is called bison, bison.

05:46In fact, the plains bison is called bison, bison, bison.

05:50That's a genus and a species and a subspecies that are all the same thing.

05:53That's the Latin name bison, bison, bison.

05:55Bison, bison, bison.

05:56It's almost as humorous as I think it's gorilla, gorilla.

05:59Yes, gorilla, gorilla.

06:00And llama, llama.

06:01That's one of my favorites too.

06:02Love it.

06:03Anyway, taxonomy.

06:04So we have these taxonomic ways of thinking about things.

06:06And that sorts everything into your deep evolutionary history.

06:09But species concepts are what people use to try to say, okay, I have this animal.

06:14is it in the same species as this other animal or a different species from this animal?

06:19And the species concept that you probably learned at Ernst Mayr's is the biological species concept,

06:24which says if they can breed and their offspring are fertile, then they're the same species.

06:30Which seems like a good place to start.

06:33It's a good place to start.

06:34Because even in my understanding from my fly biologists friends,

06:37is that you can't mate Drosophila with another species of fly and get a fertile offspring.

06:44there's some restriction. And what's wild is that flies and mammals of all sorts seem to know.

06:50Like they actually don't try to mate. In most cases, they don't try to mate

06:53with other species, which is fascinating in its own right.

06:58We might beg to disagree there. I mean, if you've seen your dog tries, your dog probably tries to

07:03mate anything it comes across.

07:04He just hit seven months. I've not seen him hump a single time. He's still intact.

07:07This time I'm keeping my dog intact. We can talk about the reasons for that health reasons. I might

07:11get them a vasectomy. People, we never talk about this, right? You can keep your dog intact and just

07:15give them a vasectomy if you don't want them to breed. Right. Yeah. Right. A guest on this podcast

07:20said that an animal expert from the Karolinska. That makes so much sense. She said, you know,

07:23in Scandinavia, it's actually, she claims, and I believe her, that it's illegal to neuter a male

07:30dog unless there's a health reason. In Scandinavia and Australia, the inverse is true. Of course,

07:34they're upside down, but we'll forgive them for that. But yeah, they need their hormones for

07:38proper brain development.

07:40Right.

07:40And we worry about them running around and breeding.

07:42There is this thing called a vasectomy, which is actually less invasive a procedure than

07:46the full neuter.

07:48Anyway, we don't want to digress too much.

07:49But my dog doesn't try and mate.

07:51I didn't see my previous dog try and mate with cats or even chihuahuas.

07:57Do you think Neanderthals and humans are a different species?

08:00I don't know.

08:01But I want to know if we are all the same species.

08:05This is an edgy topic, right?

08:08If it's somewhat based on nomenclature and if there's enough genetic variation out there,

08:15is it the case that people that we call people are actually divergent enough in terms of their DNA

08:22that two people are not necessarily both homo sapiens, that there's some homo sapiens with an asterisk?

08:27I'm not trying to cast any hierarchy.

08:29They could just be different.

08:30So you're referring to a different species concept, which is the genetic species concept,

08:36where an organism is classified based on some threshold of sequence similarity.

08:41And that is a species concept that is as valid and valuable a species concept

08:46as the biological species concept, which says you can't interbreed.

08:50If you're interested in conserving species,

08:53you might use a geographic species concept that says if you live here,

08:57you're a Florida panther, but if you live in Texas, you're a Texas panther.

09:01We're going to call you different species.

09:02Biology doesn't care about your species concept.

09:06concept is something that you have adopted to have a conversation with another person about a

09:11particular topic. Educate us on this Neanderthal piece. I know this is a topic very close to home,

09:17given that your husband works on these issues and we can, maybe we'll get him on here separately,

09:22but feel free to steal his thunder in any way that you feel. My husband, Ed Green, was part of

09:27Svante Pääbo's group when they were assembling the Neanderthal genome. And so he spent a lot of time

09:31thinking about Neanderthal. I think what's interesting from a species concept, if we start

09:37there with what's going on with Neanderthals, is we now know, based on studying DNA, both from

09:44Neanderthals that used to be alive and a different lineage of human called Denisovan, we call it

09:51this, that was first isolated again by Svante Pääbo's research group from a tiny little finger

09:55bone that they found in a cave, Denisova Cave in Russia. That's why they're called Denisovans.

09:59We know that there were multiple different species or lineages or whatever you want to call them of human-like people that were alive at the same time.

10:08And we know that after people moved out of Africa to colonize Europe, they met our ancestors, Homo sapiens, anatomically modern humans, everything you want to call them.

10:19They met groups of Neanderthals and they bred with them.

10:22So if they were a different species, they were violating the biological species concept at this point.

10:29Concepts are just what we make of them.

10:30And today, most people have somewhere between 2% and 5% of their DNA that is from this admixture event, this hybridization event between anatomically modern humans dispersing out of Africa and the Neanderthals that were already in Europe.

10:48Many questions about this.

10:49First of all, and try not to laugh, the silhouette diagram that we've seen of apes gradually in sort of time sequence working their way to bipedal and upright.

11:00When we see that diagram, is that substantiated by the fossil record?

11:04It is, yes.

11:05We know that the lineage that eventually became us evolved in Africa.

11:09We can trace ancestry back to apes and then to primates or primates and then to apes and then eventually to us.

11:17The fossil record in Africa is very fragmentary. One thing that's been really fun about working in ancient DNA is the field of paleoanthropology is pretty contentious because there are so few bones that are out there.

11:28That if someone finds a bone and it's a partial fragment of a jaw with a piece of a tooth in it, they can use that bone to completely revise what we think has happened in human evolutionary history.

11:39And maybe they're right and maybe they're not and they're smart and they've been thinking about these things and they compare it to all the other bones. So there's a lot there.

11:47What's brilliant about ancient DNA is that if I can find a little pinky bone in a cave in Denisova, right, and I can get

11:53DNA from that, I know that my bone has ancestors, right? If I have a bone that might be somewhere

12:02on that lineage to human evolution, I don't know that that bone has descendants. I don't know that

12:07that bone is part of our actual family tree, or if it's another one of the dead ends that went in

12:12a different direction and eventually became extinct. But that is one of the coolest things

12:17being able to sequence one of these bones, because now you know what it is. And now you can line it

12:23up against all the DNA from all of the people that are alive today and discover things like,

12:28we all have ancestry because there was breeding between these lineages, because they could,

12:33and because I think that if they can, they do. I would like to take a quick break and acknowledge

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§02Transcript — part 2

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15:26It's interesting, right?

15:28Because if you took the far ends of the spectrum of the, you know, the old world primate, you

15:32know, apes, and then the upright human walking, my assumption is that let's just say you used

15:37artificial insemination, that you wouldn't actually get viable, reproductively competent

15:42offspring from those.

15:43But at some point, you know, two different species, again, it's a nomenclature to some

15:48point, but to non-genetically similar, I don't want to say identical because they're not twins,

15:54right? So I don't have a language here, forgive me, but you can get breeding across species and

15:59get reproductively viable offspring. That has to be the way this happened, right? It couldn't have

16:05just been through spontaneous mutations that suddenly took animals from quadrupeds to bipeds.

16:10No, this is a very long and slow evolutionary process. It's actually a really good question,

16:15And I think it's an open question in evolutionary biology.

16:18And it's probably different.

16:20Evolution does happen because of random mutations that accumulate in a genome.

16:25And if you think about what might happen if two lineages are isolated from each other for a really long time and in different habitats, say, this lineage is adapting to the habitat that it's in.

16:37Maybe it's, you know, very rainy and there's a lot of water and there's a lot of floral plants.

16:41And over here, it's drier and there's really scrubby plants.

16:45There's different selective environments.

16:47And as mutations arise in that genome, different ones will go to fixation.

16:52The size of the population also matters.

16:54If a population is really small, even mutations that arise that are bad can become fixed in that population just because the population is small and it just happens by chance.

17:05And so over time, these two will become more and more different from each other.

17:09So what happens when they come back in contact with each other?

17:13I think it will really depend on what those mutations that arose over that time was.

17:19It could be that there's a very short evolutionary time, but a mutation has arisen that means the sperm can't fertilize the egg or the egg can't subdivide properly if you have a hybrid ancestry.

17:30Or it could be that nothing really has happened over a really long evolutionary time and admixture can happen.

17:37Humans and Neanderthals diverged somewhere 300,000 to 500,000 years ago.

17:43That's not very long ago in evolutionary time. Brown bears and polar bears diverged about half a million years ago,

17:48and we know that they can readily interbreed and do whenever they overlap in habitat. Yeah.

17:54They're called grolar bears or pizzly bears, depending on which direction. I know they're

17:59terrible names, right? You want a different name for this really cool name. Yeah, especially if

18:03you're a bear. Yeah. But that's been happening throughout their evolutionary history. We can

18:07see this because using ancient DNA, we were able to go back. We found a polar bear off the coast

18:13that probably lived more than 100,000 years ago.

18:15And it had ancestry that we see in brown bears everywhere in the world,

18:19suggesting that that bear's ancestors at some point,

18:24or that bear's descendants had hybridized with brown bears,

18:26and that DNA got passed around.

18:28We know that during the last ice age,

18:30there were polar bears that got trapped on the ABC Islands in southeast Alaska.

18:35And when brown bears expanded from the mainland,

18:38they interbred with those polar bears.

18:40And brown bears all alive in North America today have polar bear ancestry that is because of that interbreeding 20,000 years ago or so.

18:49Wow.

18:49Yeah.

18:50So in that case, a half a million years had gone by.

18:52They're really adapted to different habitats, and yet they can interbreed.

18:56But what's most interesting and I think is relevant to your question is that those hybrid bears only ever live and survive as brown bears.

19:07We see no evidence of brown bear DNA getting into polar bears.

19:12And that is, again, because of how evolution has worked.

19:16And it's especially interesting because it only really happens in the direction where the mom is a polar bear and the dad is a brown bear.

19:23Polar bears are induced ovulators.

19:25So the presence of a male will cause them to ovulate.

19:28it caused them to ovulate. So you can imagine a situation where a brown bear wakes up from

19:32hibernation, goes on to polar bear habitat to scavenge for food, comes across a polar bear

19:36female, induces ovulation, and they mate. The other way around, where a polar bear male finds

19:42a seasonally ovulating brown bear female probably wouldn't happen because the timing of overlap

19:46wouldn't be right. And also he would probably kill her rather than mate her because of the

19:50size difference and difference in what they're doing. So why is it then that since bears live

19:58that we see that have polar bear ancestry are brown bears, not polar bears.

20:01We were working with some polar bear biologists.

20:03We were doing this analysis many years ago,

20:05and their hypothesis was simply that if you have brown bear ancestry,

20:09you don't have perfectly white fur and you cannot successfully hunt seals.

20:14So it is just adaptation that means that that admixture doesn't work, right?

20:19So even though there's no problem with the sperm and egg mixing and the animal is born,

20:24they cannot survive as polar bears.

20:28separate from brown bear in that way.

20:30I'm going to bring up dogs again, but in the back of my mind is a conversation about humans

20:34and this question about different species of prior to Homo sapiens or Homo sapiens and

20:40nearby species having reproductively competent offspring.

20:43So in the dog world, it's well known that the English bulldog, which has a big head,

20:50small hips, is the byproduct of many crossings, but it's basically the bull mastiff and the

20:56pug.

20:58generate an animal with a short snout so it could clamp down for bull baiting, which fortunately is

21:03an illegal sport now, to clamp down and not get shaken off by the bull very easily. The floppy

21:09faces associated with lack of pain receptors. So a bunch of things in the bull mastiff lineage that

21:13they want, but they wanted a low center of gravity. So they took the pug. But when you cross them,

21:16of course, the females can't give birth because the birth canal just doesn't allow for it.

21:22Humans realize this pretty quickly and they learn cesarean section. So I could imagine a situation,

21:28I don't tend to think like this.

21:29Today, I'm imagining a situation where Homo sapiens

21:32and some other non-Homo sapien human-ish species

21:37were having sex, sometimes getting pregnant,

21:40but the babies would always die

21:42because the birth canal and the structure of the pelvis

21:45wasn't quite right to allow the head size through,

21:48which, you know, there are a lot of,

21:48I hear a lot of arguments that, you know,

21:50humans sort of have optimized for just enough space

21:53so that the large brain humans, you know,

21:55we love to talk about how big our brains are, right?

21:58through, but no larger and not much smaller in most cases. One of the reasons that giving birth

22:02is one of the ways that women have died in our evolutionary history. Right. And cesarean sections,

22:07I probably have changed human evolution in that sense, as has aseptic conditions and things like

22:13that. Absolutely. For me, my child was cesarean birth. Right. So I like to think you would have

22:17survived. But I could imagine a mutation that was an adaptive mutation where suddenly this other

22:24species, which maybe had a smaller pelvis, a female could deliver this child live. The mother

22:30survived as well. And then that DNA propagates so that there are now humans, maybe it's been

22:38bred out, but that there are or were humans walking around who are not completely homosapien.

22:43Or is it not possible? I don't know about what's known about hip size or anything like this,

22:49But it is true that humans and our archaic cousins, Neanderthals, interbred, and that people walking around today have Neanderthal DNA.

22:57Two to five percent, you said.

22:58Two to five percent.

22:59What's interesting about that, and it touches a little bit on the adaptation component that you raised, is that I think most people or a lot of people have heard this number.

23:09We have two to five percent Neanderthal DNA.

23:11Less well understood is that it's a different two to five percent.

23:16Like the 2% Neanderthal that is in my genome is different from the 2% or maybe 5% Neanderthal that's in your genome is different than the next person.

23:25So it could be heart, liver, skeleton, and spleen for me, and it could be some other constellation for you.

23:30It could be anything. And if we were to go around the world today and pick out all of the pieces of Neanderthal DNA that exist in humans today, we would put together more than 90%, possibly more than 95% of the Neanderthal genome just from people who are alive today.

23:48And that tells us that most of the Neanderthal genome was not maladaptive for people, that pretty much all of it could get passed on and live in healthy humans today.

24:01We don't know what happened in the other direction, right?

24:05We see Neanderthal bones and there hasn't really been any evidence of humans admins with Neanderthals.

24:11There has been evidence of hybrids between Neanderthals and Denisovans.

24:14This is really one of the most exciting things that ancient DNA has been able to contribute, I think, to understanding human disease and human medicine and what it means to be human.

24:22Because before we had the Neanderthal genome, if we wanted to know what in our DNA makes us human, we would have to compare all the humans that are alive today with our closest living relative, which is a chimpanzee or a bonobo.

24:36So there's three to five million years of time between when we shared a common ancestor.

24:41And a lot of change happens in three to five million years in your DNA.

24:45And some of it is useful.

24:47Some of it is what makes us human.

24:49And most of it is just not.

24:51It's just change because copying errors during copying cells.

24:55And that's what happens.

24:56That's how we're different.

24:57Every child that's born has about 100 differences compared to their parents because of copying

25:02error in the process of making the sperm and making the eggs that made that kids.

25:06When we got the Neanderthal genome, that 3 million to 5 million year long branch leading to us was shortened to 300,000 to 500,000 years by an order of magnitude.

25:18So now if we want to know what it is that makes us human, we have a much smaller list of mutations or variants that we can look at.

25:26And because we now know that 95%, say, of the Neanderthal genome exists in people today, we've narrowed that list down even further to that other 5%.

25:37What's going on in that 5% of the genome where no living person has Neanderthal DNA?

25:43That is where the stuff that the baby had to have the human version in order for that baby to survive.

25:49That's where we look to see what it is that made us human.

25:52A few years back when 23andMe and these other companies started making genomics in humans easier and more affordable, a lot of guys boast about Neanderthal DNA being vigor genes, whereas women try and downplay the amount of Neanderthal DNA that they have when they get their results.

26:11I found that interesting.

26:12Is there any evidence that the Neanderthal genes are, quote unquote, vigor genes, that they allow for more durability of human, male or female?

26:20It's an interesting question.

26:22look at that 2% to 5% of Neanderthal DNA that we all have, most of it is not anything that is

26:28under selection. So you see it at about 3% frequency or so in different populations.

26:33What is interesting is when a piece of Neanderthal DNA is suddenly much more common in a population

26:39of humans, because that would suggest I got some DNA from my Neanderthal ancestry, and that bit of

26:44DNA suddenly made me more fit. Because I had that bit of Neanderthal DNA, I was able to survive and

26:50have more kids than everybody else. And so it increases in frequency compared to average.

26:54And this has been a really interesting thing to learn when you think about Neanderthal DNA.

26:58There are a couple of things that have come out. There are genes that are common in Latin

27:03American populations that come from Neanderthals that predispose to type 2 diabetes. There is

27:09another gene that I think was, again, in a Latin American population that makes people feel,

27:14I can't remember if it was more pain or less pain, but it did have to do with pain sensation.

27:18And I remember there was a trial of people in Colombia where they got to feel pain in some way.

27:22And there's a Neanderthal gene associated with this.

27:25But most of the really interesting ones have been in immune-related genes.

27:30During the pandemic, one of the first alleles that was discovered to be associated with negative risk or bad outcomes of COVID was a gene that came from Neanderthals.

27:42So it's a Neanderthal-derived gene that was at something like 50% frequency.

27:48So way above the 3% average frequency in Asian populations. And it made people more susceptible to the virus

27:54entering your lungs. Presumably, it only became that high frequency because it was protective

27:59against some other disease that was circulating in the past. But the trade-off of that is that

28:05it, of course, made them more susceptible to COVID. There was another Neanderthal-associated

28:10allele that was actually protective against COVID. So I think our ancestors have been subjected to

28:18different diseases and pandemics and things that have happened throughout life.

28:20And we see the traces of that in ancient DNA.

28:23We can now go into graveyards in Europe

28:26and actually isolate plague from dirt and from bones

28:31from people who died of plague

28:32and look and see how their immune systems and genes

28:35have responded to exposure to things like this.

28:38It's really fascinating.

28:39Wow.

28:39My redhead friends like to claim that they have more Neanderthal

28:44and therefore more vigor and pain resistance.

28:48guessing the study probably said more pain resistance. We have pain experts on here that

28:52verify that indeed, on average, that redheads tend to require more anesthesia on average.

28:59So that tracks. But were Neanderthals, were a lot of them gingers?

29:03Yes. This comes from studying an MC1R, a gene that's associated with the red melanin. Mammoths

29:07as well. They had, I mean, you can see mammoth, you can see mammoth mummies with the actual hair

29:12and you can see that they're kind of, I don't know if it's because they all bleach to red,

29:18some evidence from their genome that they had reddish colored hair.

29:21Interesting. Maybe we could just briefly talk about eye color. Is it true that all blue-eyed

29:26people descended from a single blue-eyed human at one point? This almost sounds like some eugenics

29:31thing, but that's not why I'm asking. You also see a lot about how true green-eyed people are

29:37quite rare. Was there a time when the population of humans on earth had a lot more green-eyed people?

29:41I think all of the colors, if you look at African populations, mostly it's like me,

29:48dark eyes. I think that's probably the ancestral state, but there are lots of different eye

29:51colors that have evolved. And I think they're selected for, I mean, people like things that

29:55are different and unique. And so people want to mate that has blue eyes.

29:58You really think that it was selected for at the level of mating?

30:01I think probably eye color was sexual selection. I don't know what other benefits blue eyes could

30:05have other than looking very, you know, stoic and cool as you're like trying to hunt down something.

30:14Oh, geneticists are so much fun because they're willing to just go there.

30:18ask you this question later, but I'll ask now because it relates to what we're onto now. You

30:22know, we tend to think of our lives in the time bin of our lives, you know, roughly a hundred years

30:27if we're lucky, right? You know, at this stage of human evolution for about a hundred years,

30:32maybe 80, maybe, you know, if we're fortunate, 90, a hundred. But as somebody who studies

30:37long periods of time and what's happened to our species and other species across long periods of

30:41time, I'm always curious about this. I know you have to make your coffee in the morning and do

§03Transcript — part 3

30:45everything and, you know, manage your life like anybody else in, in the today and in the week and

30:49in the month and in the year. But do you, do you sit back and think of all the different tens and

30:55hundreds and thousands and millions of years that it could focus on? I'm going to focus at this time

31:00bin, right? It's a, it's an interesting way to live. And I'm just curious how you pick the

31:06problems that you choose to work on. Cause we'll talk about de-extinction, but you know, why the

31:11woolly mammoth, why not like get the Florida panthers rebooted completely? Why not both?

31:19Right. But in terms of just, you know, where to focus, like why bring back things from way back

31:24when, as opposed to, you know, maybe we could name a few species that disappeared in the last 200

31:29years. I'm guessing there are quite a few. Yeah. You know, how do you pick? And when you're making

31:35that decision, what's guiding it at the ethical level? What's guiding it at the practical level?

31:42Like what really are you trying to accomplish? Because the stuff about humans is fun place to

31:46play and put in the backdrop. We'll return to it. But your work's really focused on de-extinction.

31:52And like dinosaurs are one option, woolly mammoths are another. And, you know, just making sure that

31:57we don't lose any species that we've got right now also seems like a very, very important,

32:02indeed noble pursuit. Yes, that's a very complicated set of questions there. I think I'll start with

32:11what is motivating? And I think what's motivating is what drives the selection of the species.

32:18In fact, it's funny, I wrote a book a long time ago now called How to Clone a Mammoth,

32:22and the first chapter was how to pick a species. What are you going to do? How are you going to

32:26choose a species to bring back. And there are technical, ethical, ecological, and social reasons

32:33to pick any of the species that you can. Technical, these are the easiest, right? We can't bring a

32:40dinosaur back to life because we don't have dinosaur DNA. The oldest DNA that we have ever

32:45recovered from a bone is from a mammoth bone. A mammoth bone probably dates to around one to two

32:51million years ago. It's hard to know how old it is in that time range because there's not a really clean way of dating something

32:56within that time range. But it's old. Dinosaurs went extinct more than 66 million years ago. So

33:01that's far outside of where we're going to get recoverable DNA. And that's because the skeletons

33:06just don't... They're fossilized. They've turned into rock, right? There's no shred of DNA left.

33:12Yeah. As soon as an organism dies, the DNA in its cells starts getting chopped up into smaller and

33:18smaller and smaller fragments until eventually there's nothing left. This is really by three

33:22processes. UV light, we know about this. It's why we wear sunscreen when we go outside, but

33:27the UV light hits your DNA and it actually breaks it. And when we're alive, we have proofreading

33:32enzymes that will come and fix your DNA so you don't get cancer every time you go outside.

33:37But that is an energy requiring process. And after you die, there's no more energy. So the

33:42breaks from UV accumulate. Freezing and thawing is water molecules expand and will physically break

33:49the DNA fragment. So that's bad for DNA preservation. And most importantly, just

33:55microbial decay, the fungi, the bacteria that get into an organism when it's decaying and

34:00chew it up to transform that carbon and nitrogen into the next generation of organisms. And so

34:07that process is slower in some environments than others, exactly in the same way that your sandwich

34:13will rot faster if you leave it in the sun versus in the shelf versus in the fridge versus in the freezer.

34:20DNA will preserve for longer in the cold Arctic, where things are rapidly buried in frozen dirt,

34:26and they stay that way for a million years, like this mammoth bone that we were able to recover DNA from.

34:31But if you die in a very hot, wet, swampy place, like Mauritius, where the dodo lived,

34:37it's another one of the species that we're working on at Colossal,

34:39very little chance you're going to be able to recover DNA from any of the fragments that are on Mauritius Island.

34:45And I have tried, like, hundreds of bones from Mauritius.

34:49We have a great dodo genome, but it's from a bird that went to Europe alive on a ship and is part of the collection at the Danish Museum

34:55of Natural History. So you have to have a well-preserved sample that you can get DNA from.

35:01Ideally, many of them, because you want to know what are the DNA changes that made a mammoth a

35:06mammoth instead of another type of elephant, right? So many of them will help you to do that,

35:10but one is good enough to get some sort of template for what you're going to do.

35:14You probably should know what caused that species to go extinct in the first place so that you don't bring something back that becomes the first species to be de-extinct and then the first species to be re-extinct.

35:29Or bring back something really nasty that knocks out a bunch of other species.

35:33Yeah, you have to understand the role that that animal played in the ecosystem and whether that niche is still available.

35:39I mean, ecosystems don't live in a vacuum just waiting for something to come back.

35:45And in some cases, there's a real ecological driver for the species that we're focusing on.

35:50We feel like there is a real ecological role for these species to play, that these ecosystems are destabilized because of extinction.

35:58And by bringing back these key ecological interactions, we can make those ecosystems more robust and more resilient in the face of all the crap that people are always throwing at our natural ecosystems.

36:10Could you give me an example of that?

36:12So if you were to bring back woolly mammoths, I'm guessing that's not going to save the Amazon forest, but probably is going to do something useful based on what you just said.

36:21Yeah. So if you think about what large animals, large herbivores do in their ecosystem, they turn the soil by walking around. They knock down things. Elephants knock down trees. Mammoths probably lived places above trees, so that wasn't what they were doing. But they were distributing seeds and nutrients.

36:39Have you heard of Pleistocene Park? This is up in northeastern Siberia. There are these two scientists. It's actually Sergei Zimov, who's a Russian Academy scientist, and his son Nikita. They've been running this park up in northeastern Siberia for a long time.

36:51And they have been really interested in understanding what happens when you restore all of the species that used to live on the tundra to the tundra ecosystem.

37:01And they have bison that they've brought in from Canada and wild horses and several species of deer and muskox.

37:09And they've seen that having the animals on the landscape that they've fenced off actually causes the plants to come back with more ferocity.

37:20animals, they have to eat during the winter. So in order to find food, they scrape the snow off of

37:28the surface of the dirt. In the absence of these animals, the snow stays on the surface and snow

37:34is a very efficient insulator. So it traps the summer heat in that frozen sediment, causes the

37:40sediment to melt faster. And when the plants come back, it's a particular type of plant that can

37:46live in that moist sediment. With the animals, you get a mosaic landscape where there's some parts

37:53that are moist and wet. There are other parts that have been exposed and they're dry and colder,

37:58and you get broader diversity of plants that are coming back where these animals are. So they are

38:03essentially recreating their ecosystem just by being there. I'd like to take a quick break and

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39:21Okay, so you're picking, you don't have to pick a species, but you got to pick something of, you know, two or three.

39:28Right, right.

39:28I can't say we're going to bring back everything from a given era.

39:32So we did technical, ethical, ecological.

39:35I think another answer is what is going to make an impact, right?

39:40When I joined Colossal, we didn't have a bird program, but I really wanted there to be a bird de-extinction program because all of the tools that we are developing for de-extinction are the same tools that we can use to use synthetic biology to modify the genomes of living species and help them avoid becoming extinct.

40:01And so the kit that we're building from multiplex genome engineering to cellular rejuvenation to IPS cell technologies for wild animals to even learning the link between particular letters of the DNA sequence and what those letters actually do to cause an animal to look the way that it does.

40:22All of that is applicable across the board.

40:24So the stack that we're building for de-extinction, for synthetic biology stack, applies to synthetic biology for conservation.

40:31So when I joined Colossal and there wasn't a bird program, they had launched the mammoth program, which is a placental mammal, and the thylacine program, or Tasmanian tiger, that's a marsupial mammal.

40:42But birds are among the most endangered species on the planet, and it is not possible to clone birds using somatic cell nuclear transfer, the process that most famously brought us Dolly the sheep, because we don't have access to the egg cells at the right stage.

40:57So while that process is really pivotal and integral to our mammoth and thylacine and any other mammalian project, it's just not possible to use it for birds.

41:07And so I wanted a program that was going to help us develop technologies for birds.

41:12So why did we pick the dodo compared to any other bird for the first one?

41:17Cool beak.

41:17It comes down to that, which I also think is a really important part of talking about this project.

41:24And it's the idea of awe.

41:27of being excited about something.

41:31We get kids drawing animals,

41:33drawing mammoths and thylacines and dodos

41:35and sending them to us all the time.

41:36Ben has put them in frames up around.

41:38Some of them are good.

41:40The dodo with its sort of rounded top beak also,

41:43and the way the eyes are typically drawn,

41:46it also has a kind of cartoonish,

41:48friendly Toucan Sam type of look.

41:51It was in Alice in Wonderland.

41:52Most of what we know about the dodo

41:54is from cartoonish drawings of this animal.

41:57And of course, there's skeletons that we can piece together using the many, many bones in Mauritius that do not have any DNA in them based on my very best tries.

42:05You didn't choose to bring back like a 75 foot long python.

42:08Thank goodness.

42:09But there may be virtue in doing that.

42:11There might be.

42:12Although I think there are plenty of pythons in Florida Everglades right now.

42:15I'm not a snake fan.

42:16No disrespect to the snake lovers.

42:18But talk about bird developmental genetics for a second, not to scare anyone away, but hang in there.

42:24A few years ago, I saw something that two female condors can reproduce.

42:30Crazy.

42:31Right?

42:31And this, of course, for-

42:32It actually wasn't two female condors reproducing.

42:34It was one female condor.

42:36One female condor.

42:37Just having an egg all on her own.

42:39Yeah.

42:39And because of the sociopolitical implications, it's got people in what we're in from Northern

42:44California pretty excited.

42:46They were like, okay, we don't need men after all, right?

42:48That was the, that's always, that was the, you know-

42:50That's funny because what I heard was life finds a way.

42:54one female condor who we trust her when she says that she never mated with a male condor

43:01or a female condor, we believe her, was able to reproduce.

43:05My scientific explanation is that meiosis didn't fully separate and she ended up having a fertilized

43:11egg or-

43:12We should explain meiosis.

43:13So the separating of the-

43:14Of the cells during the very early phase when you're making eggs or making sperm.

43:20You're trying to duplicate your cell, but instead of that, you make two versions of

43:24one copy each of your chromosomes. So when normally in normal reproduction, an egg that has one copy

43:31of the set of chromosomes and a sperm that has one copy of the set of chromosomes come together,

43:35they're fertilized. The resulting eventually embryo has two copies, one from mom and one from

43:40dad. In this case, there was no sperm. There was an egg that had both copies, probably because of

43:46a mistake during meiosis. Like they didn't separate out properly and that was able to develop full

43:52term. Was the offspring viable? Yes. What's weird about that, yes. I mean, it's very, very cool and

43:59very clear the way you described it, how that could happen because you need the two sets of

44:04chromosomes. So both sets came from mom in this case and only mom, but in humans where that happens

44:10and it does happen on certain chromosomes, these homozygosity effects, they happen under certain

44:14conditions. Like there are these paternal or maternal imprinted conditions like Prader-Willi

44:19syndrome where paternal DNA gets kicked off and you have two copies from mom, which doesn't sound

44:25like a bad thing unless there are things on the paternal chromosome that are required for

44:29development. And the reverse also happens, like in Angelman syndrome, I think it is,

44:34that all the genes, everyone healthy walking around out there, you and me, and have genes

44:40that only came from our mom and only from dad. And so if you get two copies from mom of a chromosome

44:46or two copies from dad, you end up with like pretty severe deficits in brain development and

44:52other things. In some things. And you also could never be a boy because the one gene that turns on

44:56that cascade of male development is called SRY. It's on the Y chromosome. So without that gene,

45:03you would never be a boy. You would always be a girl. Trisomies where you get two copies from mom

45:07and one copy from dad, those can also be bad because of different levels of gene expression.

45:11Is Down syndrome.

45:12Trisomy 21.

45:13Down syndrome is trisomy 21.

45:14And there are a few other trisomies that are compatible with life.

45:18Trisomy 21 is the most common one because those people can live, obviously, with some challenges, additional challenges because it's an additional chromosome, but they can live full lives till relatively middle age.

45:29Is there a way of looking back at the ancient DNA of different species and knowing if they reproduce the way we imagine they reproduce?

45:37I'm not talking about the actual verb sex.

45:39I'm talking about the, like somehow sperm and egg met, but, or there was something more like the condor.

45:45You were just describing where the females were able to reproduce through these kind of unusual meiotic events.

45:51I think because, well, obviously sex has evolved a bunch of different times on the animal or the tree of life, right?

45:59And so different ways of doing sex have evolved.

46:02So we have this XY process where the males are what we call the heterogametic sex.

46:09And females have two X's and they don't have a Y.

46:12But birds do it differently.

46:13They have the WZ.

46:15And it's the females that have the two different chromosomes, the males that don't.

46:19And then there are alligators and crocodiles.

46:21And they do sex determination based on the temperature at which the egg is sitting during a very critical period during development.

46:30Yeah, there are communities online I've learned that actually believe this kind of stuff for humans.

§04Transcript — part 4

46:35There are all these theories about how to get a male or a female offspring based on position of intercourse, temperature, location, food.

46:43None of it beats chance.

46:45Right.

46:45Or if you really want ICSI, right, which is the process by which you take an egg and you take a particular sperm that you know whether it's carrying the Y chromosome or not and use that to fertilize the egg.

46:55Can you actually determine the XX or XY of the sperm?

46:59They can do that now?

47:00You can do it.

47:01You can select, so you can do true sexual selection.

47:05Because the Y chromosome is teeny, teeny tiny compared to the X.

47:09And so you can centrifuge them.

47:10And because they're smaller, they sort out.

47:13Got it.

47:13So you can spin sperm around.

47:15Don't do this at home.

47:16And then based on how the different things of different weights basically spin out to different depths.

47:21And so you can bias the likelihood that you'll get a XY carrying sperm or an XX carrying sperm.

47:26Or you can use cloning like we are at Colossal.

47:30And like we're thinking about in synthetic biology where you actually know the sex

47:33because you're starting with an actual somatic cell, a tissue cell of that animal instead of using a sperm and an egg.

47:39So let's talk about that.

47:40And before we do that, we should probably do a brief developmental neurobiology lesson.

47:44You beautifully told us what meiosis is.

47:48You know, sperm or egg, you have 20, well, in humans it's 23 chromosomes.

47:52So you only have half so that they can meet in conception and then start to divide and create more cells that become the embryo, right?

47:59And so in these other species, I guess you know how many chromosomes there are.

48:03And I must use the woolly mammoth because it's a fun one.

48:07And birds are complicated.

48:08As a developmental neurobiologist in my past, the bird stuff gets tricky, reptile stuff.

48:12Birds are tricky.

48:13They're really tricky.

48:14Some birds are trickier than others.

48:15I did not know until I joined Colossal that there are some birds that have what's called a germline restricted chromosome,

48:22which doesn't exist in any of their cells except for the germline.

48:26Germline or the sperm and eggs.

48:27And it comes into being this chromosome just in the germline, and then it disappears.

48:33Wow.

48:33I know. Biology is amazing.

48:35But birds have these mini microchromosomes that are a pain to assemble.

48:39And if you're sequencing DNA from an extinct species where the DNA fragments are really short,

48:44and you have to do it by taking each one of those really short fragments

48:47and trying to figure out where on a whole genome it goes best on a computer.

48:51We don't actually do it with like a tweezers or anything like that.

48:54Yeah, birds are really cool animals.

48:57They, from reproductive biology standpoint, it's tricky.

49:00So with the woolly mammoth was a mammal.

49:03Yes.

49:04Okay.

49:04And you know that because, I mean, people can say, well, duh, because people normally

49:08think, oh, it has fur and must be a mammal.

49:10But that is not necessarily true, right?

49:12You have monotremes and all this other stuff.

49:13So you know it's a mammal because there's evidence of lactation.

49:17How are you deeming it a mammal?

49:19Using its genome.

49:20So we've been able to sequence whole genome sequences, high quality whole genome sequences

49:25sequences from multiple mammoths that date to the last million and a half years. And we can

49:30assemble those genome sequences using a computer. And then we compare them to other animals that

49:36are alive today. And we know that the closest living relative of a mammoth is an Asian elephant.

49:42And in fact, mammoths and Asian elephants are more closely related to each other than Asian

49:47elephants are to African elephants. So mammoths are nested within the elephant family, most closely related to Asian elephants.

49:55Okay. So if you get the sequence of DNA from a mammoth, so you know, okay, this is the complete genome. And I think a lot of people probably don't realize that your complete genome is represented in most all of your cells. There are rare exceptions. It's just that not all those genes are expressed, which is why you get a hair cell versus skin cell versus heart cell and so on.

50:11That's the epigenome.

50:12Right. But the menu is there.

50:14The menu is there.

50:15Are you growing up DNA in a laboratory?

50:17No.

50:18That is the mammoth sequence?

50:19So this is what comes, I think, from Jurassic Park. And this is why I love talking about Jurassic Park, because I think everybody has an idea of how we're doing this because they saw Jurassic Park or they've thought about this movie. And what happened in Jurassic Park? And I should just say, it was not a documentary. So let's not get carried away here. Right? Okay.

50:39What happened in Jurassic Park was scientists found mosquitoes preserved in amber.

50:45They stuck a needle into those mosquitoes, preserved an animal.

50:48They sucked out a bit of stuff that happened to be blood, and it had dinosaur DNA.

50:54And then they had the little dancing DNA thing tells you about how they piece it together,

50:59and you can see the little pieces of dinosaur DNA lining up next to each other.

51:03And then there's holes and they fill in those holes with frog DNA, which was a weird choice even at the time because we already knew that birds are dinosaurs, right?

51:12So why they pick frogs?

51:13I don't know.

51:14But anyway, they filled in.

51:15Maybe they talked to Richard Harland at Berkeley or something.

51:17That's another biology joke.

51:19Look it up.

51:19But that's not actually how we're doing this.

51:22What we're doing is somehow easier than that because we know that Asian elephants are the closest living relative of mammoths.

51:31We also can, by sequencing a bunch of Asian elephant DNA and sequencing a bunch of mammoth DNA,

51:36we can see that they already have almost exactly the same genome sequence.

51:41How similar?

51:41They're about 99% similar.

51:44It depends on how you calculate the percentage and things like that.

51:46As a point of reference, how similar are we to the chimpanzees in terms of percentage similarity of DNA?

51:53In that counting, it's about the same.

51:55But some people might say, we don't look at anything like chimpanzees.

51:59Well.

52:00Sounds like so similar, like you're going to get the same thing.

52:02Yeah, well, there have been people calculate this in lots of different ways.

52:05There's some statistic online that we're 85% the same as a banana or something like that.

52:09Like a lot of our DNA is, I don't know if that's true, right?

52:12Is the goal to recreate the ancient mammoth or is it to create a pseudo hybrid of the ancient mammoth?

52:19The goal is to think about a mammoth in terms of what it does and what it looks like.

52:25And this gets back to this idea that you brought up in the beginning about a species concept.

52:30You know, this is one of the most common things that we hear. If you are going by a strictly genetic species concept where you're

52:36saying that a species, an organism is classified just by some threshold of similarity, sequence

52:41similarity to something else, that's the only way you can call it that thing. That isn't what we're

52:46doing in de-extinction. That's not what anyone doing synthetic biology is thinking about when

52:51they're designing or engineering things to solve problems, engineering animals or engineering

52:55plants to solve problems that we have in the future. The genetic species concept is an idea

53:00that was proposed to classify organisms that evolve over a very long evolutionary bifurcating

53:09phylogenetic tree process where accumulation of changes is over many generations over a long time.

53:15Our mammoths, our dire wolves are not created by that process. And so that concept really doesn't

53:21apply. I think that's where a lot of the disinformation comes. I'm going to just push

53:26back a little bit on this because what I don't want is for this sort of definitional gatekeeping

53:31to really take over and become the whole story. It's important. It's a question, but it's a

53:37narrow one. And I think it crowds out the real discussion about what it is that we're doing,

53:42how the technologies that we're developing can be applied to ecosystem health, to help stop species

53:48from becoming extinct, even as synthetic biology for human medicine. So we're not trying to make

53:55something that is identical to a particular individual that used to be alive. Our mammoths

54:00are millions of letters of DNA code different from each other. So even which one to use would

54:05be an open question. Instead, what we're doing is focusing on where all of those mammoths are the

54:11same as each other, but different from elephants and thinking that those places, like we were talking about with humans,

54:18Those are the places that are important to make a mammoth a mammoth.

54:21And that is where I'm going to focus my energy in bringing back a mammoth, which will be an elephant that is capable of living in the habitats that a mammoth lived in.

54:33Mammoths will have to live in habitats that exist today and tomorrow.

54:36So the mammoths will have to be genetically capable of living with the pathogens and the microbes and the food sources and the microbiome that the elephants that will birth them can survive in today.

54:49When you mentioned species nomenclature gatekeeping, I have a feeling this is based on the publicity around the dire wolf.

54:57Yes.

54:57Okay.

54:58I like to just address things very directly.

55:00I want to be very clear.

55:01I'm not arguing for species gatekeeping here.

55:04That's not what I do.

55:06After all.

55:07It's not even that.

55:08It's that.

55:09It's somehow this idea of what we should call it based on this very specific definition of you can only call it this if it's some threshold genetic similarity is noise.

55:20It's not an important part of the conversation.

55:22I mean, it's a part of the conversation and it's one that we can have.

55:24But if people don't want to call it a dire wolf, just don't.

55:27Right. It's like, I think like, like all things media and Hollywood, you know, I think Jurassic Park did an amazing service to science and the excitement around these concepts, but probably did a disservice as well by embedding in people's minds that the idea is to bring back the, the exact same animal.

55:45But didn't we just say that these dinosaurs were some dinosaur DNA and a whole bunch of frog DNA?

55:50Nobody looks at them and goes, no, they're not a dinosaur.

55:52Well, you're a scientist and I am too.

55:54Actually, it's funny that you mentioned this because my dad's a theoretical physicist.

55:58He was involved in chaos theory.

55:59He's been a guest on the podcast.

56:01I remember when Jurassic Park came out, he didn't dislike it, but the part where he kind

56:05of rolled his eyes was there's a description of chaos theory in there and what it means.

56:09And in Hollywood, they love to use the example of like a butterfly flaps its wings in Patagonia.

56:14And then this thing happens to the barista in Brooklyn, you know, and people like to

56:19bridge those concepts and they think, oh, that's so cool.

56:24as we say, but he was rolling his eyes. He's like, okay, that's not how these things work.

56:29And so for people that are experts in the area, it can be a little bit grading at times, but

56:33the public I think is open, right? And my experience in doing what I do is that the public,

56:38if they just have the knowledge in hand and the way you described it, great. So-

56:42So our direwolves, they have 20 edits that we picked and we sequenced genomes from

56:48fossil direwolves. We learned from those genomes what genetic changes made those animals bigger,

56:55more robust, light colored in coat. And then we engineered those changes into a gray wolf genome

57:01to recreate the direwolf. If it looks like a direwolf and it's able to fill the niche of a

57:06direwolf, I'm happy to call it a direwolf. So the direwolf was a very interesting choice.

57:11Clearly you were successful in creating this animal. It sounds like you were very intentional

57:15and picking which genes.

57:16It wasn't like, oh, we're going to take a couple of genes from the dire wolf and throw

57:19them into this other wolf and create what we call is the dire wolf.

57:23If I were to look at the dire wolf and you said a gray wolf?

57:29Yes.

57:30Side by side, is the dire wolf larger?

57:32They are.

57:33On average at the same age.

57:34Are there any other features that are visibly different or the other features more adaptive

57:38in terms of gut and ability to live in certain environments and this kind of thing?

57:42They're muscular.

57:43The fur is longer and more full, and it's also light colored.

57:48I think it's an important thing to understand about how we're selecting these because we are very deliberate about what we're doing.

57:55And it's both because we want to, with some fidelity, bring back these extinct traits so that the animals can eventually be released.

58:02Now, we're not planning on rewilding dire wolves.

58:04We will study the animals and learn about the effect of their genes on their lifespan.

58:09Yeah, I'm sorry.

58:11But the other animals, the ultimate goal is to eventually have populations of free living animals that local people are stewarding as they might like to.

58:20And so we want to understand how healthy they are, how they're going to interact with the habitat that's there.

58:25And we want to make sure that because we, with synthetic biology, have the power to engineer them in a very deliberate way, that we can do that in a way that's safe.

58:33So the hair color is a really interesting example of this and the strategy that we use.

58:38So when we sequenced the genomes of the fossil direwolves, we found that they both had variants, the same variants, in two genes that would have made them have light colored coats.

58:50But in living gray wolves and dogs,

58:54variants in those genes,

58:55not the same ones that we saw in dire wolves,

58:57but close enough to where we would need to do the edits

59:00that you have some concern

59:01that you would have bystander edits

59:03that might cause a problem,

59:04can lead to oculocutaneous albinism.

59:07So blindness or deafness in these dogs.

59:10And we decided that

59:12because we're not changing the whole genome,

59:14they have to be safe on a gray wolf genetic background.

59:17we wouldn't make the trait that way.

59:20It just wasn't passing the bar of animal welfare safety.

59:23And so instead we brought back the dire wolf light colored coat using different edits that we know are safe in a gray wolf background

59:31because there are light colored domestic dogs and gray wolves.

59:34So we use the edits that we know are safe because they exist in living dogs.

59:38Oh, that's cool.

59:39So we were able to engineer using all the tools of synthetic biology,

59:43this light colored coat that is the dire wolf light colored coat,

59:47is safe. And this is the way that we think about all of our projects. We have to take an Asian

§05Transcript — part 5

59:53elephant and turn it into a woolly animal. That trait requires changing not just the structure of

59:59the hair, but of the skin itself. We have to make room for more follicles, sebaceous glands,

60:05different approaches to be able to support that woolly coat, right? And we need to be able to do

60:10that in a way that results in a healthy animal, because these are very long-lived animals,

60:14It takes 22 months for gestation.

60:17They reach sexual maturity at 14, and it's a lot of work.

60:19So how many dire wolves are walking around right now in some location?

60:25Right now there is Romulus and Remus, and they're almost two years old.

60:30Male and female or male-male?

60:31Romulus and Remus are boys, and Khaleesi is a girl.

60:33She is about 18 months old or so.

60:36Is the intention to mate them?

60:38No, they're too closely related.

60:40We're stopping them using hormones, so rather than castration.

60:43But they live together.

60:45She was reared by herself.

60:47The boys had each other and she had just her.

60:48So she's a little bit on the like, I mean, you would never look at these animals and say, this is the way a wild wolf behaved.

60:55They were hand reared, right?

60:56But she's a little bit on the specially goofy side.

60:59But she's the best.

61:00She's adorable.

61:01Do you feel safe interacting with them?

61:02Oh, no.

61:03We have interacted with them.

61:05But the people who work with them a lot that they know feel safe interacting with them.

61:08But as they got older, it was very clear that they're wild animals.

61:11These are not domestic dogs.

61:12Remus is a little bit less skittish than Romulus.

61:14He will eventually, if you sit in the middle of where they are, he will eventually kind of sniff around and maybe come near you.

61:22Romulus wants nothing to do with you, which is funny because they're identical twins, but they're slightly different interacting with people.

61:28But it's very clear that these are wild.

61:30They're also huge, right?

61:31Yeah, how big are they?

61:32I don't have the latest measurements on how big they are.

61:35And of course, it's seasonal for all these different things.

61:37But I know that they were, at some point, they were at least like 120 pounds, which is big for a gray wolf.

61:41Yeah, that's a big animal.

61:42So everything you just said about these dire wolves, would you also say about gray wolves?

61:46Like you wouldn't want to be alone with one.

61:48Some can be skittish.

61:49Some can be calm.

61:51You know, I have good friends who are somebody you should think about having on.

61:55Actually, if you're interested in dog behavior and what we've learned about domestic dogs, I know you have a dog and it's very exciting.

62:00Elinor Karlsson is at the Broad Institute and at UMass.

62:03And she's done a lot of work with wolf-dog hybrids and then also with domestic dogs and trying to map genes to behavior and all these things.

62:12showed that breed stereotypes are just not real, that you really can't map genes to behavior,

62:17except for chihuahuas. They're just terrible. I'm just kidding.

62:20No, it's okay. We had Cesar Millan on the podcast. He'll be the first to say that in

62:24almost every decade in the United States, there was the demonized dog breed. It was actually

62:29German Shepherds post-World War II. Then it was Dobermans, same reason. Then it was the Bulldog,

62:35the English Bulldog, which having had English Bulldog is hilarious to me.

62:38I went to Georgia, so that's never going to be my least favorite dog.

62:42And now it's pit bulls, right?

62:43And statistically, actually, I think most bites come from chow.

62:46At least my uncle, who's a vet, tells me that.

62:48But chow owners, I met some nice chows.

62:51The blue tongue is pretty cool.

62:52And that's a particular variant.

62:54You can imagine, yeah, there's color is one of the things that's best understood, I think,

62:58especially in domestic dogs.

62:59There's so many genomes and all these things have been mapped.

63:03And that's part of what we have to do in all these cases is how do we figure out what it

63:08is that causes the thylacine to have the stripes that it has or causes the particular types of hair development that happen on a woolly mammoth.

63:16These are all huge open problems in evolutionary biology that I get to work on every day in my job.

63:22Clearly you have the right job.

63:26So you have these three dire wolves.

63:28They're not mating.

63:30Is the plan to make more of them, to mate them?

63:33What's the ultimate goal and intermediate goal?

63:36We will have another pack so that hopefully they will all be born more of them at the same time.

63:42So that's the plan eventually.

63:43It's not our priority right now.

63:45We're working on other species.

63:46But what we'd like to do is have another pack in the space where we are so we can really better understand the impact of the animals on the ecosystem.

63:53This is really the next rational, logical step in any de-extinction project.

63:58I often hear rumors and what are you doing?

64:00You're just going to take, get an elephant and make a mammoth and just release it into Alaska.

64:06No. First of all, no, because it's going to be so hard to make that first mammoth that I'm going to want to make sure that it is safe and cared for and has access to all.

64:15Well, this is the Jurassic Park thing again. It's that they break out. Right.

64:19But also, you know, you can't do that. We exist in the regulatory environment of anywhere that these animals are.

64:26It's not that we're some crazy scientists on an island like in Jurassic Park.

64:29We work here. We have IACUC protocols. And if you're doing anything that is releasing an animal outside, you're under the regulatory purview of a whole bunch of different agencies.

64:40I don't know if you saw, but the very first gene-edited organism created specifically for the purposes of conservation ecosystem restoration was deregulated by the USDA this week.

64:52It's the American chestnut tree.

64:55And the challenge with any of these genetically modified organisms that we have, which we're creating, synthetic biology uses a tool to make these things better.

65:03The chestnut tree is one of these stories, like the passenger pigeon, where the American chestnut was the most prolific tree across the eastern forests of North America, all the way through North America, until the early part of the 20th century, when a disease was introduced, believed to be on an import of a Chinese chestnut tree, that caused a fungus to get into these trees.

65:27And they all died. It took a decade, and a billion trees died.

65:33This scares me for a variety of reasons.

65:35A few years ago, this would be 2016, 17, I got this strange envelope in the mail to my

65:41residence.

65:42Do you know about this?

65:43No, but I'm scared.

65:44So I was living in the East Bay, California, and I get this envelope, and it contains a

65:49little kind of like, looks like a small quarter-sized plastic container, just thin, an envelope.

65:56And I had a little note, and it said, free seeds for gardening.

65:59And I was like, this is really odd.

66:01And I started fishing around on the internet.

66:03Turns out the idea was that massive amounts of seeds were being shipped from China and sent here.

66:09Now, this isn't a conspiracy, right?

66:10Like if you look at this, there are these, this is sort of attempt to just kind of like put new populations of plants.

66:17And maybe it was all benevolent.

66:18And my friends, actually, one of whom is down at Santa Cruz.

66:21I know some plant biologists.

66:23They were like, whatever you do, do not put that into the ground outside.

66:26because these things travel, birds eat them, birds poop, and then stuff grows.

66:31And this is how you can decimate important populations of trees and plants.

66:35It was the first time I really thought about vegetation on vegetation warfare.

66:39Is that actually what was happening?

66:41Is it the Chinese trying to do this?

66:43We don't know.

66:43But what is very important is that anytime you plant something,

66:47you actually want to talk to the people who understand

66:49how different ecosystems of plants coexist

66:51in the same way that you wouldn't put your wolves out into the dog park.

66:56I wouldn't put the wolves out because if we released dire wolves,

67:00they would compete with gray wolves.

67:01And gray wolves are already having enough trouble trying to find a way to survive.

67:04And so there's no need, there's no ecological need to release gray wolves into the habitat.

67:08And so we can use them to study these.

67:10But if you think about what you just said, right?

67:12I think people, we as a lineage, have been messing with the evolution of the stuff around us for as long as we've existed, right?

67:24Initially, just by driving things extinct.

67:27Not deliberately, right?

67:28Just like maybe this wasn't a deliberate attempt to have some plants that would outcompete other things.

67:34No, maybe they like those particular flowers, yeah.

67:34But we did.

67:35And we changed ecosystems by going into them and getting rid of all the largest animals that were there.

67:40Or the trappers.

67:40Because we were hunting them.

67:42you know, our ancestors in, you know, 50,000 years ago in Australia, 30,000 years ago in Asia.

67:48And then we domesticated things and now we conserve things. And when people think about

67:54conservation, a lot of people have this idea that it's this beautiful thing where you're just

67:58leaving everything alone. But that's not what we're doing. We are deciding how many of them

68:03get to live, what they get to eat. We vaccinate them. We protect them from predators. We,

68:07I'm not saying that is bad, but I think it's naive to say that it's not us determining what the future of these animals are.

68:14And we've also been moving stuff around forever.

68:17Like we have English birds all over the place here and in New Zealand that were brought by people because they liked them, right?

68:24They liked them where they were.

68:25And I think it's a mistake to imagine that the only good ecosystem is the one that you know right now, because you're claiming a particular slice of history as the thing that is better than everything else.

68:39And I think it's more important to think in terms of robustness.

68:43And you said, go back to the beginning, you said something about how when we have multiple things happening, multiple species in an ecosystem that are all doing different things, you end up with more biodiversity and richer environments.

68:57When there's an overlap in ecological niches, there's some redundancy there.

69:01And that redundancy is really good for that ecosystem because it means that bad stuff can happen and it can weather that bad stuff.

69:10So maybe we shouldn't always think in terms of bringing in something new is bad.

69:14I should have planted the seeds.

69:16No, I'm totally on board with what you're saying.

69:18I don't mean to plant the seeds.

69:19No, no, no, no.

69:20I'm totally on board with what you're saying.

69:22It touches on an important theme that we've certainly never discussed on this podcast,

69:26but it's very relevant to today's discussion and that people should think about,

69:29which is, you know, who gets to decide?

69:32It's interesting because there's both a kind of like massive ego inserted into the notion

69:36that like we know best about everything, including the other, all the other species of plants and

69:41animals. That's obviously not true, but also that we don't have anything to contribute in terms of

69:46our own evolution. That is, I mean, look here, you're a human being bringing back species of

69:52past. And some people might think scary. Other people might think fantastic. I think why it's

69:58hard for people to wrap their head around these things and they default to thinking about, oh,

70:02was better in the past is because a most people never experienced that they have no concept i

70:07think there's a great book that i had to read years ago called uh the good old days they were

70:11terrible but we hear the good old days you hear about all like the dysentery the lack of antibiotics

70:15like but we tend to look back and say oh that was it must have been so nice back then everything

70:19bucolic and beautiful and you forget all the the dark side of that right but the other one is that

70:24we don't have a window into the future right and so you know i went to school in santa barbara and

70:29one of the first things you learn there is that there are all these species of fox that are out

70:32on the Anacapa Island and Santa Rosa Island and all these islands that the Chumash brought out

70:38there on boats. But no one says they don't belong there. They say there's this incredible

70:42biodiversity out there, which is why it's protected, why we don't have a lot of tourists

70:46walking around out there. We want to protect that. But humans brought those out. But the fact that it

70:51was Native Americans and it was some time ago leads to our percept like it was good, right?

70:56And so the idea that we would remove them, no, we need to protect them.

71:00And that makes total sense to me, but it's a default psychology that I think is driving a lot of the quote unquote ethical conversations around this.

71:07Right.

71:07Because we don't have a window into the future.

71:09So let's say these dire wolves, you make more of them.

71:11I can get totally on board the idea that then there are wild lands that they are roaming, that they are serving other populations of animals and plants.

71:20There's new interactions that are benevolent interactions that are pro-evolution as opposed to devolution.

71:26think the challenge for people is we don't know what that looks like. And it feels like there are

71:32too many variables to understand. So I'm just wondering how you wrap your head around that

71:36when you're talking to people about what you do and when you're thinking about what you do.

71:40I'm thinking in terms of helping ecosystems to become more resilient. We know, for example,

71:49because of what happened in Yellowstone, the impact that restoring the top predator of an

71:54ecosystem that had been removed can have. The gray wolves that were reintroduced into Yellowstone,

71:59the population of animals that they ate had become too large and they had eaten away at all of the

72:05shrubbery. And so putting the gray wolves back in Yellowstone cascaded all the way down that

72:11ecosystem ladder to changing the way the rivers were flowing because the plants were growing back

72:16now along the edges of the rivers. The thylacine, which is the Tasmanian tiger, this is the second

72:24declared as one of our de-extinction targets.

72:26The thylacine was the top predator in Tasmania.

72:30And Tasmania today has problems because that top predator is missing.

72:36Have you heard about or seen the awful pictures of the Tasmanian devil facial tumor disease?

72:42Yeah, this came up on a few podcasts ago because we had Jared Rutter,

72:45who's another Hughes biologist, or some mitochondria.

72:49We're talking about there are no transmissible cancers,

72:51but these Tasmanian devils have wound-induced cancer-like problems.

72:57So they fight, they scratch each other up, they get cancers,

73:00and that population is suffering as a consequence.

73:02And they're so closely related to each other that they can pass them between each other.

73:07Oh, so it's the genetic similarity that allows that to happen.

§06Transcript — part 6

73:10The point is that I, yes, this is terrible, but if we had had the top predators,

73:15those sick individuals would have been weeded out of that population,

73:18and we might not have this problem.

73:22restoring that ecosystem. And also, I'll get back to, you know, I often get the question of,

73:28why are you thinking about bringing extinct species back to life? Why aren't you thinking

73:33about helping living species not become extinct? And the answer is, we are doing both. It is the

73:39same tools. It's the same technology. It's the same needs. And when we excite people with the

73:47idea of mammoths and dodos and thylacines, we get more engagement and enthusiasm and investment

73:54in developing the technology that we can use to stop living species from becoming extinct.

73:59There's a really great story. Our Colossal Australia partners have been working on a

74:03project to try to stop the northern quoll from becoming extinct. Have you ever heard of this guy?

74:08I'm familiar with the quoll. Most people won't.

74:10It's Q-U-O-L-L. So it's a little guy. They're adorable little.

74:13They're super cute.

74:14carnivorous marsupials, and they eat amphibians. And in Australia, there is an introduced amphibian

74:23called a cane toad that is toxic. It's toxic to dogs. When dogs eat them, they die. It's toxic

74:29to everything. When a quoll eats a cane toad, it dies. And that's terrible. And there is a very

74:36strong chance in the next few decades that northern quoll is going to become extinct.

74:40However, there is a synthetic biology solution to this, and it's one that has actually already been made, right?

74:47There are mammals that eat toxic toads that live on the other side of the planet, even that eat cane toads, right?

74:54And they have a single letter change that changes one amino acid in one gene that allows them to eat that toxic cane toad and not die.

75:03Our Australia, Colossal Australia partners, have made those changes in a quoll.

75:07And when you measure in a dish the ability of that toxin to break down the cane toad, that single letter change to that quoll's genome could allow that quoll not only to avoid becoming extinct, but to eat cane toads, which currently nothing really can in Australia.

75:23So now we can see the real benefit of this massive comparative biology framework.

75:29I know which gene it is that I need to change.

75:32The stack that allows us to develop the tools to be able to make that change, just that change,

75:37and then show that that's the only change that's there.

75:39You've made what you wanted to do.

75:40And then put that in a living animal can stop a species from becoming extinct.

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77:18membership. Again, that's functionhealth.com slash Huberman. As someone who does a lot of

77:24public science, health, education interaction, there are a couple of things that get the public

77:30really worried and that they need reassurance on. Honestly, I think it dates back to the pandemic.

77:35There's a lot of distrust about scientists. There is this belief that some scientists

77:39are only concerned with themselves.

77:42It's an important myth, in my opinion,

77:44to dispel the idea that most scientists

77:45are not what I believe them to be,

77:48which is they're trying very hard to get answers right,

77:51to do good for the world, including other species.

77:54And they're not so careerist

77:57that they're willing to overlook that.

77:59Independent of the IRB boards and the thing,

78:01the constraints that force them to do that.

78:04But that is the era we're living in, right?

78:06So I think that some people think more now

78:09Scientists are like doing stuff because they can.

78:12This has parallel conversations about AI where people are thinking like, hey, like, have

78:15we really thought this one through?

78:16And people are scared.

78:18But I totally agree with what you're saying.

78:20And I want to talk about two species to try and highlight this and how it can be done

78:25right.

78:25Because I think it's clear that you're trying to do this right.

78:29Which means for the best possible outcomes for humans and other species.

78:33And the first are mosquitoes.

78:35And the second are humans.

78:36Most people don't care about mosquitoes, but some years ago, I started paying attention to mosquitoes because your very own Howard Hughes director now, I think Leslie Vosshall, works on the olfactory system of mosquitoes and other insects.

78:51And it turns out bugs find mates and find things to suck blood from and et cetera by odors and pheromones, but odors.

79:00And so there was this idea, oh, mosquitoes have malaria.

79:03This wasn't Leslie's idea, but it was like, mosquitoes have malaria.

79:06Let's just get rid of all the mosquitoes.

79:08And the biologists were like, no, you can't do that because then the birds are going to suffer because they eat the mosquitoes and on and on and on.

79:14I mean, this stuff can really domino.

79:16It sounds like a great idea.

79:17It's a terrible idea.

79:19Or let's just make mosquitoes that can't reproduce.

79:22That's a great way to do it, right?

79:24Or let's just do in half of them, right?

79:26There were these ideas just kind of thrown out there that with genetics, you can do that.

79:30release a few of these little suckers into the wild, then there is the potential that they mate

79:34and proliferate and just enough to eradicate a population or half a population. It's harder to

79:39do than that. So people didn't know this was like being explored, but smart people put the brakes on

79:44it. So let's talk about mosquitoes. Like they clearly carry pathogens that harm people, but

79:51they're also important for ecosystems, vitally important for certain ecosystems. So how do you

79:56think about plucking out a node in an ecosystem, like a species, or introducing a species back into

80:04an ecosystem and thinking about the ramifications? It's hard to model behavior in one species,

80:09let alone interactions between species. How do you wrap your head around that? Maybe the mosquito

80:14would be, I hope, a simple example of this. Mosquitoes are a hard one. And I think that

80:19they do cause a lot of death and disease, but not all mosquitoes. So the only certain species of

80:26mosquitoes carry malaria and dengue and other diseases that are known to affect people. And

80:32also those mosquitoes have much higher population density because of the way that people have built

80:39our towns than they would have had in natural ecosystems. So for something like a mosquito

80:45that is extremely overpopulated and carrying a devastating disease,

80:49I would think that there actually is reason to think that it is safe in an ecosystem

80:54to at least bring that population back down to a size that it would have been in a natural ecosystem.

80:59And a lot of problem with mosquitoes is because people leave just tubs of water

81:03or water that isn't circulating out and they lay a billion eggs and then you have many more mosquitoes.

81:08That's not true in the Arctic.

81:09In the Arctic, there's a bazillion mosquitoes and no people and it's really miserable.

81:12But I've spent a lot of time in my life.

81:15It sounds horrible.

81:16So I do not like mosquitoes.

81:17I don't like mosquito bites.

81:18And I get it.

81:20Like at first blush, I'm like, get rid of all the mosquitoes.

81:23But it's a lot more complicated than that.

81:24Maybe engineer mosquitoes that they can't carry the disease rather than engineer the

81:28mosquitoes to be dead.

81:30I mean, there are ways that I think we can use synthetic biology.

81:32And gene drives is the thing you were getting at where you release something that is created

81:37by synthetic drive into the wild.

81:39And then it passes on to the next generation.

81:41I actually think that gene drives are an incredibly powerful way that we have at our fingertips where with the appropriate safety measures and care in place, we should think about how we might deploy these tools.

81:52You can make a gene drive so it only lasts for a fixed number of generations.

81:57And also because they tend not to make things reproduce, there is incredibly strong natural selection against them.

82:03Anything that breaks a gene drive and lets something reproduce is going to be favored in a population, right?

82:09So gene drives are going to be difficult to get to persist.

82:12And there are many switches that we could build into them to make them last for a short period of time.

82:16But there are some species that have taken over.

82:20You talk about your plants that you got.

82:22In this part of the world, there's cheatgrass everywhere.

82:25And it's highly flammable.

82:26And it grows alongside the rose.

82:28And it's Mediterranean in origin.

82:29And the only way we are ever going to get the cheatgrass down enough to be able to let the native California grasses come back

82:38is if we get rid of the cheatgrass for a few generations. Do you think this is one of the reasons there's so many

82:42fires? They're very flammable and they also don't have very deep roots. So in California,

82:48it's very dry, right? California native grasses have much deeper roots and so they stay green

82:52longer. So they're sequestering carbon and they're not as flammable for longer into the season. These

82:57shallow rooted Mediterranean grasses dry out super quickly. So as soon as it's fire season,

83:01like it is now, they're ready to go, right? And it's not just here, it's all across the

83:05western part of North America. And this is a problem. And it's a problem because it causes

83:10huge amounts of damage to forest ecosystems, huge amounts of property damage when fires take off,

83:15and they're out competing these grasses. This is a situation where I would say,

83:18let's think about how we might safely deploy something like a gene drive that can remove

83:23something or at least tamp something down enough to allow that ecosystem to become, again, once

83:29again, more robust and resilient. As far as, you know, what do we think about adding things back

83:35system. This is one of the reasons that every de-extinction project or every species translocation

83:42project is staged and thoughtful. When people moved Texas panthers into Florida in the mid-1990s to

83:50try to stop Florida panthers from becoming extinct, they had developed crooked tails and cowlicks and

83:56cryptorchidism. Their testicles didn't descend and they were going to become extinct. This was an

84:01inbreeding depression. There were only a few individuals, so they only bred with individuals

84:06they were related to. There was no choice. You bring in the Texas panthers and the panthers

84:10recovered. All of these diseases disappeared for a short period. Now they're inbreeding again

84:15because the population is cut off from Texas. And so they'll have to keep doing it. We have to be

84:20the stewards of these ecosystems that we're creating. But that's in our power. We can do

84:25a ton of analyses about potential risks and rewards of what might happen when we modify an

84:32ecosystem. And we do it all the time, sometimes to good ends and sometimes to bad ends. What we

84:39can't do, and I think this is sometimes where the conversation gets lost, is if you look around,

84:48We see habitats around the planet that are suffering because of changes that people have made.

84:57Within those habitats, there are species that are teetering at the edge of extinction.

85:03And the only strategy that they have to survive is natural selection, evolution and natural selection.

85:09The rate of change of these ecosystems is too fast for that to work.

85:14If we say these technologies that we have, whether it's translocations or assisted reproduction or genetic modification and synthetic biology and de-extinction, if we say that those technologies are too risky, we are accepting the outcome of doing nothing, which is also a decision.

85:35And I think that's where a lot of times the conversation gets lost.

85:40Doing nothing is not not deciding.

85:42Doing nothing is saying we accept the fact that we are going to have a future that is less biodiverse than the present.

85:50It's amazing how people are perfectly happy to allow the negative default outcome to emerge, even though it's the consequence of humans.

85:59But they are wary of humans intervening to a potentially better outcome.

86:05It gets back to this issue of trust in scientists.

86:07And it also raises the question of who decides.

86:10I'm very opinionated about this when it comes to public health policy.

86:14I think what the pandemic taught us, regardless of where people sat on vaccines and lockdowns,

86:19if nothing else, it taught us something absolutely essential, which is you can't have one person

86:24be the spokesperson.

86:25Right.

86:25People need to hear from a group, including the dissenters in that group, and why they

86:31arrived at a particular decision.

86:32I should be clear for all of the species that we're working on, we have advisory panels that are built from local people. We have the Tasmanian advisory panel that has politicians and people who grow forests to log them and people who work with the animals and people who are scientists and conservation biologists.

86:50And we have regular meetings with all of our different advisory groups to talk about what the future might look like well before we have a thylacine to be able to release anywhere.

87:01Our MOA project is led by the Naitahu Research Center in South Island of New Zealand.

87:05And these Maori people are the people who will be the long-term stewards of the MOA.

87:10And the decision about how many to make, which MOA to make, where to release them, how to release them, it's their decision.

87:17in consultation with other people who will be impacted by this.

87:21And I think that's really important.

§07Transcript — part 7

87:22The other thing that I think we do well is this, right?

87:26I mean, I am not a scientist hiding up in an ivory tower somewhere.

87:30I'm here talking to you and talking to as many people as I can

87:35to tell people all about what we even get yelled at for this.

87:38Why is Colossal always talking about what Colossal is doing?

87:41Well, would you rather we not tell you?

87:42I mean, I think the education piece is the critical piece.

87:45I think it's great that the colossal is doing this.

87:48I mean, it is true.

87:48I think we are all desperate for when the dire wolf story broke.

87:54And there was a small subset of scientists who were just yelling at me that I wasn't allowed to call it a dire wolf.

88:00And there are a bunch of people who are like, wow, I can't believe you learn from a bone and actually use the tools of synthetic biology to engineer extinct traits into a living animal.

88:08And now you have living dire wolves, right?

88:11And there were people who were scared of it and people who loved it.

88:15There were a bunch of people who said the word extinction and synthetic biology for the very first time in their lives.

88:21And I got emails from my colleagues at universities who said the undergraduates were coming into their ecology classes and their sociology classes, their anthropology classes.

88:31Some of them were mad and some of them were excited, but they were talking about it.

88:35And they were talking about it as if they had some agency in the world that they were inheriting.

88:40And we hear that from middle schoolers and high schoolers.

88:45And I think that is really something tremendous about what we're doing. People need to feel excited and positive and they need to feel

88:51awe. And when I saw the direwolves for the first time, that's what I felt is genuine awe, right?

88:59And there's something about that that just makes the world a better place. It makes people happier

89:04and healthier. And I love that I get to talk about it and do this hard science, like really hard

89:09science with a bunch of smart people every day. As long as we're wading into deep water here,

89:15Let's talk about the really deep water, which is humans.

89:18Okay.

89:19So we have this thing called IVF, where people can make embryos and select what are deemed at this point healthy versus unhealthy.

89:29So people are doing genetic selection in humans through technology, right?

89:33People don't really stop too often and think, oh, yeah, you know, how is that disrupting the human ecosystem in any different number of ways?

89:40But a few years back, there was a guy in China, actually who had been a postdoc at Stanford, who decided to use gene editing to modify the genome of some babies.

89:51Disrupted the HIV receptor.

89:53And there are two stories about this.

89:55I don't know which one is true.

89:56One story is that they did it for benevolent reasons to prevent these babies from getting HIV from either an infected parent or to just protect them against HIV.

90:06The father was HIV positive.

90:07The other story that was running in parallel was that this modification might have some impact on hippocampal or other brain circuit function that might make them hyperintelligent in one dimension.

90:20So this was kind of more of like a eugenics experiment.

90:22That was the idea.

90:23And it was very interesting how this emerged.

90:26Not in the general public.

90:28Like that was interesting in its own right.

90:29But there was this short moment of about a week where it wasn't clear if this guy was going to win a Nobel Prize and be celebrated or was going to be put in prison.

90:39Yeah, I remember this.

90:39It was Antonio Regalado broke the story about a week before the big CRISPR conference.

90:44There were these emails that suddenly came out.

90:46And it was very clear, like people were kind of tap dancing around this guy.

90:49Like, what's going to happen to him?

90:50Do I want to be associated with this and glean some of the benefit?

90:54Or is he going to be demonized, in which case I want nothing to do with this guy?

90:57He's like, he's blacklisted.

90:59It turns out it was the latter, right?

91:01And the Chinese government said, yeah, we're going to shut down his lab.

91:04He's going to be punished.

91:06I don't know what's happening, if he's running experiments or if he's in prison or what's

91:10happening.

91:10But this was so interesting, right?

91:12Because since then, there's been no fewer than four major companies launched for deep

91:18sequencing of embryos, both from IVF, but also non-IVF babies.

91:24And I have people coming up to me saying, hey, guess what?

91:29We just got to screen these embryos and we were told which of them is going to have the

91:33highest IQ and which of them is going to be tallest and which of them is going to be this

91:37and which one and that.

91:39And so some of these companies are geared towards ruling out disease.

91:42Right.

91:43Others are geared towards trying to optimize for best possible outcome.

91:48Right.

91:48Now, this gets people riled up because it's very expensive at this point.

91:52So that has other implications.

91:53Right.

91:54And it's easy to say, oh, well, that's like eugenics.

91:59But when people select who, assuming they do it voluntarily, who to have children with, they're selecting on the basis

92:04of a number of features, some physical, some emotional, some resource related, some cognitive,

92:11you know. And so there's a lot of this happening, happens in the animal kingdom. And in humans,

92:17it's happening now at the level of genetic sequencing. And I think we're headed for

92:22big discussions about ethics, about changing quote unquote ecosystems through genetic selection of

92:29it. It's happening. There's a really fascinating story that comes partly out of ancient human DNA

92:35literature and speaks directly to this, this idea that I think we feel uncomfortable with things.

92:40We feel comfortable with new technologies initially because there's kind of this reptile

92:43brain thing going on where first we have to decide if we're scared of it before we can decide if we're

92:47curious of something, right? So there's initial pushback there. But we are doing, as you say,

92:53genetic selection on humans by choosing our mates. And it makes us uncomfortable even to think about

93:03that. But here is a relatively benign example to show that that's true. And it has to do with human

93:10height, right? So we know, unlike IQ, which is very difficult to pin down which bits of your

93:17genome mean IQ, and IQ as measured by what, and what are you at? And it's different in different cultures, and so that's hard.

93:24But height is relatively easy, and we know that it's heritable.

93:27So we know that there's bits in your DNA that can mean that you're tall or short.

93:30I'm five feet tall, so I didn't get any of the tall genes, right?

93:33I'm little.

93:34But we know now, by looking at the ancient human DNA, that in Europe, at least, where

93:39there's a lot of very tall people in Northern Europe, right?

93:41The Dutch are extremely tall.

93:43I remember going to the Netherlands and imagining that I was going to be like speciating there,

93:47where I would be walking in between people as they were above me, you know?

93:50Like driving a tiny car with a lot of big trucks on the highways.

93:54Anyway, that's kind of what I feel like when I walk around the Netherlands.

93:56The Dutch are very tall.

93:57Very kind, but very tall.

93:58Very tall.

93:59But we know that a lot of these genes were first introduced into Europe with the steppe

94:03people at about 4,700 years ago at the Yamnaya, and that originally they were migrating.

94:08And for a long time, we thought that people were just getting taller because of environment.

94:13They were learning more about health.

94:14They're learning more about what they should eat.

94:16And yes, there is some true to that.

94:17But height in Northern Europe has kind of plateaued now.

94:21And people have reached what seems to be the tallest you can be with this set of genes that exist in people today.

94:27But it is there.

94:28It's in Northern Europe.

94:30It's not in other parts of the world, right?

94:32And so there is human genetic selection for a trait that we can visibly see that makes people look different from each other.

94:39That isn't because somebody's picking an embryo and a sperm in a dish.

94:43So we would be naive to imagine that it doesn't happen, that it hasn't happened throughout our evolutionary history, or that we can control it.

94:50But I think what offends us about it, this innate reptilian brain part of us, is that while we don't care that a chihuahua and a boxer, we pick, we engineer to have different traits because they have different roles in the society because we have created the roles for them in society.

95:11We created them.

95:12They were once gray wolves.

95:13We like to think of people as not having niches to fill, as having some freedom of choice to be able to pick what they want to do and what they want to be.

95:22And this idea that one generation might do something to take that away from the next generation just sits really uncomfortably with us.

95:31It's wonderful that you're doing public education on these things because I think people really need to understand that there are well-meaning scientists who are not just trying to figure out what would happen if.

95:43that it's clear that there are going to be more things like this, right? And so we have to navigate

95:49forward with that. Similar to AI, it's not going anywhere, just like smartphones aren't going

95:53anywhere. And the question is, what is the best use of this, the safest uses? And where can it

95:58evolve our thinking in our lives in really unforeseen ways, unforeseen positive ways?

96:03We're really only just beginning to see this. I mean, you know, the story of baby KJ, the first

96:08child who was cured of a genetic disease using the tools of synthetic biology. This was a child

96:15that was born with a urea cycle deficiency. His blood was building up in ammonia. And because

96:22people, scientists, had done a ton of research on this particular condition and really understood a

96:27lot of what was happening, they were able to identify the cause of this genetic disease.

96:31And then it was a collaboration between academic, industry, NIH, the Children's Hospital Philadelphia

96:38This huge collaboration came together, took six months, designed a base editor, CRISPR base editor, to target his particular cells, come up with a delivery mechanism to get it into his liver, do all of the testing that you need to do to make sure that it's safe, and then give him a CRISPR medicine, a bespoke CRISPR medicine as a six-month-old kid three times, and he is cured of this disease and will live a normal life.

97:04Amazing.

97:05And no one accuses those doctors of playing God.

97:08Right. That's what's so funny. I mean, here, I guess we're sort of exploring in the background,

97:13like what establishes the line?

97:15How is that not playing God in the same way that anything is playing God? I think we play God

97:19every day. And in Judaism, there's actually the idea that you're supposed to take care of the

97:25natural world out there. So you're actually playing human in this case, instead of playing

97:29God when you're using the tools available to you to actually make the world and the people around

97:34you better and healthier. When we took a gray wolf and decided we were going to let its puppies live

97:39in our campsite as hunter-gatherers 30,000 years ago, we were making a decision that impacted

97:44another species. As we took teosinte and turned it into corn, every decision that we make about

97:51which populations of species to protect and which not to protect, to decide to allow quolls to have

97:57this genetic modification so they can survive in the habitat that we changed by introducing cane

98:02toads. These are all decisions we make that fall into that category of exerting human influence on

98:08the world. But the world today is a human world. And the species that live today and thrive today

98:14are those that have figured out how best to do that in the niches that we have created for it.

98:19And we need to just deal with that and get better at it. Use the tools at our disposal.

98:24Can I ask you about ferrets?

98:26You can.

98:27And I also want to talk about stuff that lives underwater.

98:30That ecosystem has all sorts of issues that it needs to deal with.

98:34Humans probably have to intervene really quick or we're going to be in trouble.

98:37So ferrets, they're not rats.

98:39They're carnivores.

98:40Great binocular vision, great hunters.

98:42But a few years back, the black-footed ferrets were almost extinct.

98:47My understanding, this might be wrong, was that it was that the prairie dog population

98:52got out of control when the numbers of black-footed ferrets were diminished. And as a consequence,

98:58the grasslands were being eaten up like crazy. And that had all sorts of downstream negative

99:02consequences. So it was important to reestablish the black-footed ferrets, not just because they're

99:06cute. And my understanding is that it was one ferret, Scarface, who sired like 300 litters

99:12or more, and they were able to resuscitate or at least partially resuscitate the population.

99:18So I'm curious which elements of that recollection are false and also whether or not there's any concern about diversity given that it was one male siring all these litters and so you get a bunch of kits and they're mating.

99:32But mating of close relatives is bad for genomes for reasons that sort of emerged earlier is you get homozygosity.

99:39You get genes that are too similar.

99:40And then if you have most people are dominant alleles where you only need one copy, okay, that's a separate matter.

99:48But with normally many mutations, you need two copies, recessive alleles.

99:51But if you get genes that are very similar between brother and sister, you're likely to have two recessive alleles and you get bad mutations.

99:57And you can get deformities and sterilities and low IQ.

100:01It's a very interesting thing that throughout all species, inbreeding is bad.

100:06To a point, the island foxes, the Channel Island foxes that you talked about, this is a really fascinating example of a population that was so small for such a long time.

100:18and lived in a pretty steady environment with no predators,

100:21that they went through that bottleneck where all of those bad mutations were expressed

100:25and purged from the population.

100:27And they have almost identical genomes.

100:30They have almost no genetic diversity, and they are perfectly healthy.

100:33Wow.

100:34I don't know if something happened to that habitat, if they wouldn't be able to survive,

100:38because there's no diversity.

100:39If a disease came in, they would all be susceptible rather than some versus not.

100:44And that's a very protected region.

100:46I know that because my college girlfriend was an environmental studies major, and they used to go out there, and it's very protective.

100:52You can't just, like, take a boat and, like, stomp around those islands.

100:55But it's fascinating.

100:56It is fascinating.

100:56It's fascinating.

100:57It is fascinating.

100:58But in general, my understanding is that reading with close relatives is really bad, certainly for humans, which is why in Iceland and Scandinavia, there's these incredible genetic records dating back to when there were fewer foreign opportunities to mate with foreigners, right?

101:13Yes.

101:13We're going to be blunt about it.

101:16deal with these black-footed ferrets because it's an example of this dynamic tension between

101:20trying to reestablish a population and wanting enough genetic diversity.

101:25Yeah. And it's also a great example of how we can use multiple tools that we have for genetic

101:30rescue simultaneously to help a species. I should say that the black-footed ferret project is not

101:34something that I was personally involved with. This is a project that's been a collaboration

101:38of U.S. Fish and Wildlife and the San Diego Frozen Zoo and Revive and Restore, which is a

101:42nonprofit conservation organization. I was on their board for a long time. And they're doing

101:46really fun work. But the story is interesting. The story is that the prairie dogs, which black-footed

101:52ferrets eat, were a real pain in the butt for farmers. And so they wanted to get rid of prairie

101:57dogs. And so they set out all these ways of just trying to kill a whole bunch of prairie dogs. And

102:01it killed a couple of prairie dogs, but it killed almost all of the black-footed ferrets instead.

§08Transcript — part 8

102:06And so we ended up with a situation where black-footed ferrets were nearly extinct in the wild. People brought them

102:12into captivity, but they could not figure out how to get them to breed in captivity. And eventually,

102:17the last captive animal died, and then the last wild animal died, and they thought the species

102:22was extinct. It was actually on the, I think it's the class of 1966, the first list of endangered

102:28species when the Endangered Species Act first passed, black-footed ferret was. But then,

102:32like a decade later, Shep, the family dog of a family that lived outside of Matitsi, Wyoming,

102:39killed a black-footed ferret while it was out one night.

102:42And the story is that the family took it in to a taxidermist,

102:46and they were like, we want this because it's kind of cool.

102:48Like, what is this?

102:49And the dude was like, I'll be back.

102:52And he went back and called somebody and was like,

102:54I think we have this extinct species here.

102:57And it was proven that it was a black-footed ferret.

103:00So there was a population that persisted around Matitsi, Wyoming.

103:04People started studying this population again,

103:06And they went and they collected a whole bunch more individuals, brought them into captive breeding and knew more about this.

103:12It was a real international push to figure out how to make these animals breed in captivity.

103:17But then they noticed that the animals in the wild started to get sick.

103:20And in a last ditch effort to save them, they went and collected every individual that they could find in the wild.

103:26And I believe one of them was Scarface, who is the one that eventually like bred with everybody and ended up having a bunch of diversity.

103:33Scarface, he had a scar on his little black footed ferret.

103:36are so cute. I recommend everyone who's hearing this, look them up. Don't get one as a pet,

103:41trust me. So this is a successful captive breeding program. And every year they can

103:46release about 500 black-footed ferrets into the wild. But there are two problems. The one is what

103:52you mentioned, and that is that there's not that much genetic diversity. There were a handful of

103:56founders in this population. All of them were from the same population near Matitsi, Wyoming. So

104:01they're already closely related to each other. And over time, the amount of diversity in that

104:06population is going to decline. So a few years ago, this collaboration of organizations got

104:12together and said, there's a solution to this. In the frozen zoo in San Diego, there are tissue

104:20samples from that original captive breeding population, unrelated to the individuals that

104:25were in Matitsi, Wyoming. So different genetic diversity. If we could use cloning, the tools

104:32that we will use to make mammoth, that we use to make our direwolves, that most famously was used

104:36like Dolly the sheep, we can take those skin cells and turn them into a living black-footed ferret.

104:44So revert them to stem cells?

104:46Not in this case.

104:47You just take an egg that you've harvested from another one and you inject the cell into the egg.

104:51And the proteins in the egg itself can do that epigenetic reprogramming, which is kind of like reverting,

104:56but you don't need the Yamanaka factors.

104:58You just need the egg to do this.

104:59So it becomes a cell that starts to divide and become all the different types of cells that make up an animal.

105:06Elizabeth Ann was born.

105:07Elizabeth Ann was the first clone of 40-year-old tissues from an animal that had lived decades earlier.

105:14She was not reproductive, unfortunately.

105:17She was never able to have offspring.

105:18By behavior or there was some biological wiring issue?

105:21There was some wiring issue.

105:23Her ovaries weren't releasing the eggs or something.

105:26I can't remember.

105:26Ferrets have this induced ovulation thing, too.

105:29They have a kind of funny, funny.

105:31I mean, to us, it's funny.

105:33To them, it's perfectly normal.

105:34But they did make another one.

105:36And from the same line, and that animal has reproduced and there were offspring from that that can be able to be

105:41introduced. So here we have a solution to introducing genetic diversity into a population

105:46that had lost genetic diversity on the path to extinction. But there's another problem.

105:52And that is that the thing that's actually killing the black-footed ferrets in the wild

105:56is plague. Bubonic plague? Plague. Yes. That's another reason you don't want to have a ferret

106:03as a pet.

106:04Well, definitely not a black-footed ferret.

106:05I mean, the European, you don't want to send me off on a thing.

106:09I had a pet ferret, I believe, many years ago, and I don't recommend them.

106:12But you were going exactly where I'm going.

106:14It was a domesticated ferret.

106:15It was not the black-footed ferret.

106:18Domestic ferrets are not susceptible to plague.

106:23And that susceptibility must have some genetic underpinning.

106:28So if we can figure out what that is, and there are several hypotheses

106:33working on right now, we could use the tools of synthetic biology, genetic engineering,

106:37to edit the genome of these black-footed ferrets and make them resistant to plague. So not only

106:43use cloning, a form of genetic rescue, but then also synthetic biology to create animals that are

106:49able to survive in this habitat, despite that people have mucked with that habitat in a way

106:54that makes their survival hard. We can use these same tools for lots of different things. We have

106:59a project related to our dodo project with the Mauritian pink pigeon.

107:02Is it actually pink?

107:03It's pink.

107:04It's very pink.

107:05You pick cool animals to wear.

107:06You're like, woolly mammoth dodo bird pink pigeon.

107:09You know, like, you know, you guys know how to, you know, get-

107:12It's part of it, right?

107:13Oh, a dire wolf, you know.

107:14And the dire wolf thing, my understanding is that it was also on the heels of like the

107:18Game of Thrones popularity.

107:19So that was like a piece.

107:21If you weren't going to make a dragon, you might as well make a very large wolf because

107:23it has these kind of connotations.

107:25When I was working on the first direwolf genomes way before I was involved with Colossal, but the very first time we published direwolf DNA, we were desperate to sync the publication with some editor in some science journal to the Game of Thrones coming out.

107:40We were like, we can get this genome done.

107:42Surely they'll want our paper because then they can have some press attention to the direwolf paper.

107:47We never got the DNA finished in time to do that.

107:50It was so poorly preserved.

107:52They lived in warmer parts of the world, and so it was really hard to find samples that had high-quality DNA to be able to get.

107:59It was a fun project, though.

108:00Were the babies cute?

108:02Yes.

108:02Yeah, okay.

108:03They didn't come out ferocious.

108:05Yeah.

108:05No, they were extremely adorable.

108:06Just putting a plug in for the dire wolf here.

108:09Extremely adorable.

108:10I bet.

108:10I bet.

108:11Everyone loves a baby animal.

108:12Yeah, well, that's how we got dogs, I'm pretty sure.

108:14They were hanging around outside, cleaning up after us, giving us a little bit of an advantage,

108:19because if something scary came, like a giant cave bear or something,

108:22they would howl and our ancestors would know.

108:25But I'm pretty sure that that was just commensal.

108:27We could have lived for a long time with them living around us

108:30and us living around them, but I think their puppies were cute.

108:33Yeah.

108:34And you make a really good point.

108:35I mean, you know this notion of like the eyes of the getting rounder,

108:39like in dog breeds, you know, because people like them.

108:42I mean, all the doodle breeds, the hypoallergenic breeds, they don't have fur.

108:46I think about that sometimes because I have two Labradors

108:49permanently coated in at least one layer of dog shed hair.

108:54We're so comfortable as humans to modify species for our immediate convenience.

109:01But sometimes that's obviously detrimental to entire populations.

109:04You're talking about reintroducing a species that have not been there in a long time or

109:08expanding their numbers.

109:09I would like to think that with AI or other modeling tools that you could make predictions,

109:19predictions about, okay, let's model in the mosquito population, where the swamps are,

109:25what the seasons are like, what the quoll population looks like. And you could put,

109:30you could model as many things that you're aware of. There's no graduate student, no matter how

109:35brilliant, or professor, no matter how brilliant that can mathematically model all the different

109:40influences of all these different plant and animal species. But AI can run it 24 hours a day,

109:46seven days a week. This idea of digital twins. Can we create a digital twin of an ecosystem and

109:50then perturb it in lots of different ways and see what happens? I think this is totally within the

109:54realm of feasibility. It's a big foundational model, but I know there are groups of people

109:58who are working on this for smaller systems, like individuals to think about human medicine,

110:03what happens in this system, this particular organ system, if you perturb it in this way and using

110:09AI to be able to narrow down the window of what edits might be reasonable to make and what might

110:16We're doing other things. We have a completely independent group of people that make what we're calling our care reports, which are deep dives into the ecosystems where we would be releasing any future de-extinct animal.

110:28We release these when we have them with the blue buck. We have a blue buck care report that people can read to figure out what we've thought about in terms of the impact of the ecosystem over short, medium and long term.

110:39And it involves conversations with local stakeholders and conservation biologists and people who are thinking about it from all sorts of different perspectives.

110:47So it's absolutely, as you say, critically important to think hard before doing things, but also be willing eventually after you understand as best you can what that risk was.

110:58Yeah. Along those lines, I predict in probably three to five years, not 10, the technology that we were talking about earlier of mutating the HIV receptor, that sort of thing will be very commonplace in the context of fertility.

111:13I mean, if we knew a certain constellation of disease genes inevitably led to a disease or a high probability of disease, and there was a way to use gene editing to rule those out,

111:23Once that had been established a number of times, I'm willing to bet even outside the

111:27Bay Area that people would want that.

111:29Nobody wants a harder life for their child.

111:32Right.

111:33You know, it could also come, I've thought about this, my last book is called Life As

111:37We Made It.

111:38And it's all about how we've been messing with the species that we encounter for as

111:41long as we exist.

111:42In the last chapter, I think about how we might turn our editing technology on ourselves,

111:47really asking the question, what is it that will push us over that edge, right?

111:53One of the possible scenarios is that we have a pandemic, a crisis, and we learn that there are certain people who

111:59have a particular genetic variant that means that they will die. And suddenly the most morally

112:05reprehensible thing that we could imagine doing becomes the actual only ethical solution. And that

112:11is the thing that pushes us over the edge. You mean, so you're talking about more people dying

112:16or rescuing that through gene editing? Gene editing ourselves. And now we're talking more

112:23about public perception, scientists and implementation and where those intersect.

112:25And I think that one thing that I've learned

112:28is that a lot of it is about the delivery method.

112:31So when we hear about gene editing

112:33and you're taking a cell and you're putting in a dish

112:35or even ICSI, what you described before,

112:37like in a dish of basically injecting a sperm cell

112:42into an egg as opposed to running a sperm race, right?

112:45People are a little more comfortable with that

112:46than they are like the ICSI.

112:47It's like this one, we're taking this one already

112:50because you're biasing an outcome in a strong way, right?

112:53You're not letting the system decide.

112:54But people are okay with this if, for example, you have a man with a very low sperm count or with very few healthy sperm where you can take a healthy sperm and put it in the egg.

113:05Yeah.

113:05No, I think people are comfortable with it now because it's been around for a while.

113:09It's this every new technology you have your first, is it scary?

113:12Right.

113:12Like, why do I hate this before?

113:14Let me be curious.

113:15Yeah.

113:15I mean, in a different conversation, but one that is relevant, you know, it's fortunately we're not talking about it today, but, you know, I get asked about peptides like every

113:23five minutes these days and not the peptides of the GLP sort. But what's happened in the health

113:28space is that the GLP drugs have de-stigmatized and taken away needle phobia by putting the,

113:35it's still a needle, but it's on a pen. And so now people are like, which peptide should I take?

113:40And I'm like, how do you get it? No one's saying like, is there a capsule version anymore? That

113:43was a big thing. And now if you're like, because it turns out it's the hypodermic part, not the

113:47needle that freaks people out. The needle kind of freaks people out, but people have no problem taking a pen and going

113:53But they don't like using a plunger and a needle.

113:55So now people, needle phobia has plummeted and people are willing to explore things that some of which there's good data on and some of which there's like no data.

114:04And people are pinning themselves all over the country, right?

114:07And so it turns out that something, this couldn't have been predicted, that there was this other thing that was getting in the way.

114:13It wasn't really the thing about taking the peptide that may or may not have enough data.

114:18There are a lot of data on the GLPs, but it really was the delivery method.

114:23computers, right? They were big clunky things. Everyone had to use the same one. Then all of a

114:27sudden you turn it into a phone that's also a camera. And the next thing you know, you kind of

114:30forget that it's a computer. Same thing with brain machine interface. As long as people think you

114:34need to drill into the skull or put something, a wire behind the ear, pretty soon this will be

114:38non-invasive. And then people aren't thinking about, oh, it's going to control my brain.

114:42So that big fear wall tends to come down to zero through these things that are hard to predict.

114:50and it's often a combination of the messaging

114:53and kind of like,

114:54like maybe everyone should pet a dire wolf just once,

§09Transcript — part 9

114:58just a little bit.

114:59Would you like to pet a dire wolf?

115:00I would love to pet a dire wolf,

115:01especially the little ones, but yeah.

115:02You should come visit us in the lab

115:04and you'll see some of the really cool stuff we're doing.

115:06The artificial wombs are really cool artificial eggs.

115:09You know, there's a-

115:09You have artificial wombs?

115:11We have one of our-

115:12You realize this is going to terrify people.

115:13I'm a biologist, but okay,

115:14so describe to me an artificial womb

115:16and what that looks like.

115:16Right now we're thinking about mice, right?

115:20So the idea is if we're going to have hundreds of mammoths, we're not going to get there by having 100 Asian

115:27elephants pregnant for 22 months with mammoths. We need a way to be able to birth multiple

115:33mammoths simultaneously without using elephants. Elephants should be allowed to make elephants,

115:38right? And so we'll need to build the technology to do this. But building that technology is also

115:44an opportunity to build technology that can really help people and can help other species,

115:51but really thinking mostly about people. I have a friend who was diagnosed with breast cancer

115:56during her pregnancy, and she had to make a decision about not starting the therapy until

116:00she gave birth or taking a giant risk with the baby. What if we could just take the baby out

116:05and be able to put it in a place and have it completely develop, and then she could start

116:10the treatment a couple of months earlier? Or if a baby needs surgery, but you can't really do it,

116:14inside, have a safe way to have that baby come out. These are all technologies that are,

116:20will be feasible in the future that are motivated by de-extinction. How crazy is that?

116:25It is wild. One of the most incredible things that I've witnessed is a NICU. It's a different

116:32form of what you're describing, but it's incredible. Like you go in these places and

116:35it's room upon room and it's super quiet and, you know, they try and keep it dark. And I mean,

116:40Like these are artificial wombs, so to speak, right?

116:43These are so preemie babies and some of which are very preemie.

116:46Some have issues and some don't.

116:48Some are just early, which is an issue of its own kind.

116:51But the NICU technology has come a long, long way.

116:55It's far from perfect, but that's essentially what you're talking about.

116:59Yes, a more sophisticated NICU where we've learned so much more because of the complementarity of understanding

117:10how genes map to phenotypes and being able to use all of the genetic resources that are available to us

117:15from all of the people and learning about epigenetics and building this technology that

117:20builds on what we understand about the developmental process. I mean, we are facing a future that I

117:25think is really exciting and spectacular, maybe a little bit scary, but I think as long as we keep

117:30talking about it and having conversations about it way before it's possible, we can get to a place

117:35that people are comfortable with and people are excited about. There seems to be a theme lately in

117:40where people come on this podcast

117:41and they're talking about revolutionizing education.

117:43We had someone, the principal of Alpha School, come on here.

117:47Kids spend two hours a day on their iPad

117:50learning from an AI tutor that knows exactly what they need

117:53to fill every gap in their knowledge.

117:54Cool, I need that.

117:55Two hours a day.

117:56Then they go learn how to farm, start businesses.

117:59It was interesting that public reaction is very divided on that.

118:02People usually say, great, and then other people say,

118:04oh yeah, but it costs a lot, so it's only for rich kids.

118:06It turns out they're starting scholarship programs.

118:10But the idea there is to figure out the best way to educate humans,

118:13and then wick it out to everybody.

118:14But there has to be this pioneering spirit,

118:17and that's always going to stimulate concern,

118:19and there's going to be the haves and have-nots things in people's minds.

118:22I think thinking about your work in a different but similar vein,

118:25where being a pioneer is hard because you have to tolerate people saying,

118:32and sometimes the assumption that you're doing this just for your own self-interest,

118:36it's all financially driven,

118:37And what about the, you know, what about the starlings that, you know, need our help right now?

118:42There's always this like, what about the things that need our help right now?

118:45Why are we doing this?

118:46And I don't have any great solutions for you on this, but I think that public education is clearly a big part of it.

118:52And I think the humanizing it at the level of who's doing it, like it's very clear that you love biology.

118:59It's very clear that you like hard problems in biology.

119:02And it's very clear that if I may, it seems like you're not afraid of, but you rather enjoy the fantasy positive outcome part of it.

119:12It's not all doom and gloom.

119:13I mean, this is similar.

119:14This example works for me.

119:16Hopefully it works for you.

119:17You know, like Elon wants to go to Mars.

119:19And I have guests on the podcast that say like, no, he should be curing humanity here.

119:24And I told that person, that's like telling, you know, the Metallica they should be the Grateful Dead.

119:31We need individuals who are thinking in a different way steeped in really good ethics and are excited

119:36about the problem to evolve this thing that we call life on earth. Sure and I'm good with that

119:41if people say to me oh why are you working on this you should be curing cancer those are two

119:46different things although you know there's things that weird. You know what quit this I don't know

119:50you but quit this and go cure cancer. Well I mean we are learning things from elephants for example

119:55that we have to know about and that is actually relevant to curing cancer but that's not our main

119:59I'm not focusing on curing cancer, but people who say you should do this instead of saving living species, I just really have to push back on that.

120:07We are doing both.

120:09There is not enough money in conservation.

120:11There just isn't.

120:12The idea that we're developing tools that are immediately applicable to existing conservation problems using new funding, new resources, bringing in new investment ideas, excitement, enthusiasm, excitement from students.

120:26I mean, why is this not embraced?

120:29Why is it always the, well, you must not be doing that.

120:32We are doing that.

120:33The dire wolves, when we announced the dire wolves, we announced that we had cloned red wolves, which is the most endangered species of wolf in North America, an endemic wolf that, again, is living in a very small population, captive breeding in the Carolinas.

120:46We had colleagues, Bridgett vonHoldt, who is at Princeton, who had discovered a population of coyote-like animals that have a bunch of red wolf ancestry, some on the order of more than 75% red wolf ancestry.

121:00And so we've cloned these wolves as a means to introduce new red wolf genetic diversity into the existing red wolf population using the same toolkit that we used to be able to clone and generate our dire wolves.

121:13Have you heard about our red wolves?

121:16No, they were announced at the same time though. So all these people who are like, you should be doing this instead of this,

121:21pay attention. We are. They've saved the ginger wolves. I love it.

121:26There's something that I think people need to understand about scientists and probably

121:31technologists too, but that's not my area, which is the person matters. Like the person doing the

121:36work has to be really, really drawn to almost obsessed with the project. Because you could

121:43sort of ask like for any scientists there are a lot of scientists working on kind of pedestrian

121:47stuff in my opinion used to review a lot of grants for NIH and go like sometimes those to get funded

121:52sometimes not but but that's the kind of science that certain people do they want to turn a crank

121:57and then there are certain scientists who really want to be out on that like really cutting edge

122:01and they have to be obsessed with the question otherwise you get nothing in the same way that

122:06I think Elon's pretty obsessed I don't know him but with this going to Mars thing and I don't think

122:13he's got a bunch of other stuff going on clearly, but you can't really draw them off target by saying, hey, why aren't you working on curing cancer or building, I guess he is building flying cars.

122:19So the example of musicians to me just works.

122:23Like you can't get Metallica to play the Grateful Dead happily.

122:27They're just not going to do it.

122:28It's not in their spirit.

122:29It's not in their soul to do it that way.

122:32And so I think that like we have to accept this about people and the people who move things forward like Howard Hughes, the very Howard Hughes, right?

122:40He liked his aircraft, right?

122:43He liked, you can't convince people like, oh, you should be saving the coral reefs. Someone else should be saving

122:47the coral reefs, but they need to be obsessed with coral reefs. I mean, I'm stating the obvious,

122:51but I think from the inside, I relate. Yeah. Also, people shouldn't feel bad about not being

122:56able to do everything. If you think about the amount of time that you have in your life,

123:00if you try to do 10 things instead of one thing, you're going to get way less done. You're not

123:04going to make an impact. It's so interesting. People love to tell other people what to do,

123:08But I will say there are people out there, I know this because of this podcast, there are people out there who are enchanted by biology, that are enchanted by what you've told us today, that are excited about these species and can imagine the positive outcome.

123:25And some of them are young and some of them are old.

123:27But God bless the young ones because they're the ones, it only takes a few of them in a certain area of science to really move things forward, as you know.

123:33So where are the public education efforts outside of podcasting and whatnot?

123:38How many people are at Colossal?

123:40There are about 120 scientists, and then there's other people involved.

123:45We have a huge social media team who put a lot of science bits out for the world,

123:50targeting different audiences with different types of information.

123:54We work with a lot of podcasters, and we work with other teams of people making documentaries and films.

123:59We publish papers using the traditional old school peer review process.

124:04We post some papers on the archive if we think it's important to get the information out faster before peer review.

124:11So we're trying lots of different methods of communicating.

124:14And of course, I go out and talk to people.

124:16And I'm a National Geographic Explorer.

124:18So I do take part in the National Geographic Live series.

124:21So I've gone and just talked to communities about conservation and genetic rescue and de-extinction and a future that can be both biodiverse and filled with people.

124:31So in junior high, high school, graduate school, were you sitting there thinking, I'm in a department of zoology at Oxford University, and there's a picture of some old dude on the wall.

124:41This is how I felt when I went to Cambridge.

124:42I'm like, that's Darwin's house.

124:46There are two ways to be in that kind of environment.

124:48like, whoa, that's so-and-so and there's this history,

124:52or was it, we can do this all much, much better?

124:55Because I get the sense that you like to break the mold,

124:58but I don't want to kind of lead the witness here.

125:00So what were you like as a kid and in graduate school,

125:02were you thinking, you know, this field,

125:05this whole zoology thing feels kind of steeped in old stuff

125:08and I want to break it open?

125:11Or, you know, like maybe just tell us a little bit

125:13about your mindset in these kinds of environments.

125:18My origin story. I think I always disappoint people with my science origin story. I went to the University of Georgia as a broadcast journalism

125:23major. I had worked for the local TV station in the corner of Northwest Georgia where I grew up.

125:29I was on air in the mornings. I did local cut-ins on headline news at 24 and 54 after the hour.

125:35When I went to the University of Georgia, I was actually the news director of a local radio

125:39station that was there, which was not particularly well aligned with being a freshman at the

125:44University of Georgia, we'll just say. I was living in a dorm that had a shared bathroom and

125:48I had to be at work at four o'clock in the morning to write and cut the news so I could be on the

125:53drive time show. Do you remember these from the 90s? So I had an opportunity to take a class

125:59after my freshman year and it was an honors program class and it was geology and archaeology

126:07and it was a nine-week class and we started off on the East Coast and learned about minerals,

126:14and the sort of coastal dynamics on the coast,

126:17drove across the country, sleeping in national parks,

126:19drove up the West Coast, drove back across the country,

126:21and learned about the formation of the national parks,

126:26the landscape that is the U.S., right?

126:29And I thought to myself, as I was watching this,

126:31you could see the scars on the landscape from glaciers.

126:34And we went to all of these archaeological sites

126:38and anthropological sites and saw the impact of people on the ecosystem

126:42and the impact that we had on those people.

126:44And I thought, this is the kind of story that I want to tell.

126:47Maybe I want to be a science journalist instead of just a regular journalist.

126:52The idiocy of people who think they're an expert because they've done something for a few years.

126:55I was like, I already know how to be a journalist.

126:57I'll just learn how to be a scientist.

126:59And so I started taking science classes.

127:01I ended up going to Panama, living on a place called Barro Colorado Island, and studying parasitoid wasps.

127:08And I wasn't doing anything related to genetics or really evolution.

127:12It was ecology, population ecology.

127:14And I met somebody there who was starting up a lab in Edinburgh.

127:18And I thought he was really smart and interesting.

127:21We put together this proposal of a project that I could do as a PhD student where we were going to study the type of wasp that switches back and forth between inbreeding and outbreeding.

127:31So the question was, is the switch to inbreeding something that is intended to purge your genome of those deleterious alleles like the Channel Island foxes?

127:39Like if we inbreed, we'll get rid of all that bad stuff that's accumulated.

127:42Then we can go back to outbreeding.

127:44It's a pressure test.

127:45Yeah.

127:45So we designed this experiment.

127:46I went back to the University of Georgia.

127:48I was like, I'm going to go to Edinburgh.

127:49This is going to be great.

127:50Help me apply for these scholarships.

127:51And they said, cool, because I couldn't afford to go overseas for grad school.

127:56And I said, cool, you can apply.

127:58But you have to apply for all of the scholarships that we have for our honors program people together because it's just one big package.

128:03So I applied for the Marshall Scholarship to go to Edinburgh and the Rhodes.

128:08And I did not get a first round interview for the Marshall.

128:11So I ended up not obviously being able to go to Edinburgh, but I got a Rhodes scholarship.

§10Transcript — part 10

128:17So I ended up at Oxford.

128:18So you are a true, I think you're our first Rhodes scholar, you know.

128:21I got Rhodes.

128:22I ended up at Oxford.

128:23I had no idea what I wanted to do or who I was going to work with.

128:27And I met on my first few days there, this guy called Alan Cooper, who's a Kiwi.

128:33He was setting up an ancient DNA lab.

128:36This was one of the few labs at the time that was going to be built to be able to process these old samples.

128:42And I was really excited about the idea of ancient DNA because it brought together geology and paleontology and storytelling.

128:52If I'm reading DNA sequences from entire ecosystems that used to be alive, I can tell a story about how the environment changed when people first arrived or how the environment changed with rapid warming out of the last ice age.

129:06And I was like, this is the science I want to do.

129:08Plus, it was brand new.

129:09Nobody was doing it.

129:10There were a couple of dinosaur DNA papers that had been published and proven to be false.

129:14And it was really an opportunity to bring stuff together that hadn't been done before and just do something entirely new.

129:22If I joined his lab, I could go to Siberia.

129:24And that was enough for me.

129:24I signed on the line.

129:25I was like, I'm in.

129:26So that's my origin story.

129:28And I think it is because it was new, because it was an opportunity to bring together lots of different disciplines that, you know, otherwise really hadn't been thought of together.

129:39I got into de-extinction because everyone who works in ancient DNA is asked as the first question whenever they publish a paper.

129:48This is, you're working in ancient DNA.

129:52We're doing stuff that's high profile. We get high profile papers. It's normal in science for this thing to happen. You get

129:57interviewed by somebody from the media and the first thing they want to know is,

130:00so what does this mean about how close we are to bringing dinosaurs back to life?

130:04Every time, every time. I'm more concerned about the black-footed ferrets, frankly.

130:08When I was researching my second book, I was using the New York Times Wayback Machine,

130:14which is amazing. Love the Wayback Machine. And I was reading the very first article

130:19about the very first ancient DNA publication.

130:22In 1984, researchers from Berkeley

130:25in what was called the Extinct Species Study Group

130:28had managed to isolate using molecular cloning,

130:31because this was pre-PCR days,

130:33a tiny little fragment of DNA

130:35from the skin of a preserved quagga,

130:38which is an extinct type of zebra,

130:40and show that it was related to a zebra.

130:43So the scientific finding was not that illuminating,

130:46but the fact that DNA survived after death,

130:49first discovery of that. So it wasn't a big deal. It really set off all of the stuff that became

130:54the dinosaur DNA days of ancient DNA. Could lead to forensics.

130:59All of the forensic stuff. Yeah. All of that came out of this too. But when the journalist

131:04interviewed Alan Wilson as the very first ancient DNA researcher, publishing the very first ancient

131:09DNA paper, he got to be the first person to ask the dinosaur question. The dinosaur question. Yes.

131:14I mean, it is true that if you walk into the life sciences building at Berkeley, there's a full size T-Rex skeleton.

131:20It's cool.

131:21It's very cool.

131:22People love that.

131:22I've never been dinosaur obsessed.

131:24I can think of many more animals and human diseases that to me are more interesting.

131:28But this is like the why don't you cure cancer thing.

131:31Yes.

131:31Well, but I think we get to mammoth because as soon as people hear that and understand that we can't have dinosaurs because there's no dinosaur DNA, they tend to settle on mammoth.

131:40Either mammoth or saber tooth cat.

131:42Those are the two things that we get after that.

131:44it's just because they're big. You know, it's this big thing. We know they're extinct because

131:49our ancestors hunted them. We know they're relatively recent. We can imagine what they

131:54looked like. They're in popular culture a bit. And so it's a matter of awe, of interest.

131:59I think it's the size and scope that is, they make us feel small.

132:03Yeah.

132:04Yeah.

132:04People don't like to feel small, but mammoths make us feel small too, I think, but in a

132:08way that we can appreciate.

132:10Yeah. There's something about the psychology around this in terms of public perception

132:14I'm going to go with that people want the best for our species and other species on average.

132:20They're a little scared based on, for reasons that make perfect sense to me,

132:23based on what they know and what they don't know.

132:26For that reason and many other reasons,

132:27I'm just grateful that you'd come out here and talk about this stuff today

132:30and that you're doing what you do.

132:32I thought the dire wolf thing was super cool.

132:34I still do.

132:35You should come see that.

132:36I got it.

132:37I'm not saying that, you know, as a biologist, I got it.

132:40As a, you know, developmental biologist, I was like, I got it.

132:44This is not like taking some human cells from the cortex and putting them into a mouse cortex. Like those are cutesy experiments.

132:49Frankly, I thought those experiments were more like cutesy derivative. They didn't really

132:54inform or anything in my opinion, but what you guys did, I thought was really cool. And then as

132:59I started learning more about what you're trying to accomplish, like repair ecosystems, make better

133:03ecosystems, I'm all for progress. So thank you for doing what you do, for continuing to do what you

133:09do. I didn't even get into the fact that you walked away from a fully thriving lab in academia,

133:15Howard Hughes Investigator, which is this thing that very few attain. And so to do this, so clearly

133:21you're on a mission and I have every anticipation that it's going to work out and work out for the

133:25best for animals and for people. I'm excited to see what you guys do. Thank you for the opportunity

133:30to have this conversation. Yeah, it's a lot of fun for me. I rarely can I talk about ferrets,

133:35woolly mammoths, dinosaurs, and human gene editing

133:38all in one conversation.

133:39Thanks so much.

133:40Thank you.

133:41Appreciate you.

133:42Thank you for joining me for today's discussion

133:44with Dr. Beth Shapiro.

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