Becoming Martian (featuring Dr. Scott Solomon)

25:45And so the Polynesian people are really, they're really the world's most successful navigators. I mean, it's just incredible that the ancestors of the modern Polynesians were able to discover all of these tiny specks of land by setting out in canoes without having maps. They didn't know where to go. And yet they found these places and they successfully set up settlements there. I would die. It is really amazing. I've flown to some of these islands and you spend like hours of the plane over nothing but water. And then you see a tiny dot emerge and you land on that tiny dot. And it's like, wow, I'm so glad that dot is there.

26:27Imagine not knowing it's there, just like setting out and hoping to find something. It's remarkable. I mean, the ultimate needle in a haystack, right? So one of the amazing experiences I got to have in researching this book was actually going to this site on an island. in the Society Island. So this is near Tahiti. And this spot is thought to be the jumping off point for some of those great voyages of discovery by the ancient Polynesians. So it's now, it's an archaeological site. It's actually a sacred site called Tapu-Tapu-Atea on the island of Raiatea. And this is the place that was a center of learning.

27:12It was a center of training for navigators and for leaders. And what they would do is they would take a stone from that structure and bring it with them on their voyage. And then when they made it to land, they would use that to establish this new site. So they think that that's where people who ultimately made it to Hawaii, to New Zealand, and to Easter Island, that's where they started. And so when I was there, I'm looking at this place. It's this big, wide expanse right next to the edge of the sea. And it's like a flat, square, or rectangular area made of volcanic stone. And I'm looking at that, and I'm realizing this is a launch pad.

27:57I mean, this is their equivalent of, you know, setting out into the unknown. You load up your canoe with all of the supplies that you need to set up a new settlement somewhere you've never been. And it must have been as terrifying as, you know, loading up a rocket and setting out into space. Because once you're out in the open ocean, it's not like you can stop and make repairs. If you forgot to bring something, you're pretty much out of luck. And I think, you know, Martian settlers would essentially have to do the same. I'm going to note that my research brought me to Washington, D.C., and yours brought you to Tahiti.

28:35So I did something wrong and you did something right. But do we know how long their journeys took? So like a mission to Mars is like, what, six to nine months. How long were the Polynesian people on the water en route to a new island? I don't think we actually know. I mean, we've only been able to reconstruct this from a combination of like archaeological records as well as some genetic studies. You can sort of see the genetic relationships among people living on different islands today and even some of the linguistic evolution that kind of tracks those same things. So I don't think we actually know that much about the voyages themselves.

29:12But, I mean, it must have been, you know, weeks at least, if not months, right? Some of these are really far apart. I mean, I think Easter Island, the closest land, is like 1 ,200 miles away. So it's a long way. And so then bringing it back to Mars, the idea is that we can study migration on these islands to get a sense for what it might be like for humans to live on Mars. I guess some of the issues are things like population bottlenecks and founder effects. What do we learn from studying how this happened on these islands? And what does that tell us about what it might be like for humans on Mars?

29:47Yeah, so we know from studies of like animals and plants on islands that there are these things, like you said, like founder effects, where the founders of a new population have a really big impact on the potential for future evolution of that population, once it's established. And one of the things that often happens is they are only a small subset of all of the diversity of the population that they came from. So usually you get a reduction in genetic diversity. They don't represent all of the traits, all of the characteristics of the population they came from. And you also can have random fluctuations in which certain traits become more common or less common, not because they're useful or harmful, but just because of random chance.

30:41And that happens a lot in really small populations. And we call that genetic drift. And so the question is, would that apply to humans in the same way that we know it applies to animals and plants? And so studies of people living on Pacific islands actually suggest that the answer is yes. There's some evidence of genetic drift and founder effects happening in island populations. Can you give us some of those examples that you used in the book? There were some fun examples there. Yeah, absolutely. So one of the kind of famous examples comes from the HMS Bounty, so the famous mutiny on the Bounty, right?

31:22So this was in the late 1700s, and the Bounty was a British ship that was making its way through the South Pacific. And they stopped at Tahiti. It's a lovely place. The crew got very attached to some of the inhabitants, some of the Tahitians, and they decided they didn't want to leave. And the captain was telling them, no, we got to leave. And the crew was like, we're staying here. And they had a mutiny. and the mutineers ended up escaping and setting up on another island. So this is a small subset of the original crew, and they had some Tahitian wives. They ended up having children with those Tahitian wives.

32:06And the population kind of grew very slowly at first, but once it did start growing, they had to relocate to another island, the island of Norfolk. And if you go to Norfolk Island today, the majority of its inhabitants can trace their descendants back to the mutineers from the bounty. And so, interestingly, they show evidence of having genetic drift and having a founder effect because there's kind of a reduction of genetic diversity in that population compared to other human populations. And there was a study that showed that they are shorter on average than other folks, which seems to be connected to this reduction in genetic diversity.

32:53Are they more likely to mutiny? Or to mutate. Jury's still out on that, I think. Mutation on the bounty. That's the biological version. Oh, yeah. That's a good name. And I'll just share one more if I can, because there's another really interesting example, which is also a Pacific island. In this case, it's an atoll called Rangelop in Micronesia. And in the late 1700s, around the same time as the mutiny on the bounty, there was a typhoon that unfortunately killed the majority of the human inhabitants of this island. Some of the few people that survived, I think there were only about 20 or so survivors.

33:34And one of the survivors, perhaps not surprisingly, was the king or the leader. And he happened to have a rare gene or an allele, a version of a gene, which is the allele for complete colorblindness. So not like the more common red-green colorblindness, but basically if you have complete colorblindness, you see the world in black and white. You don't see any color at all. Now, he didn't have complete colorblindness. He just carried the allele. It's a recessive allele, so you need to have two copies of it to be completely colorblind. But because there were only a small number of survivors, and basically in the next few generations, you ended up getting a lot of inbreeding, then that meant that those recessive alleles were more likely to show up in the same individual.

34:30And in a few generations, you got the first truly colorblind individuals. And so now that island has the highest proportion of complete colorblind people in the world. And so, again, it's not because that was advantageous. It doesn't seem to give you any advantage to be colorblind, and it might actually even be kind of a hindrance. But just because of that population bottleneck, because they were reduced to a few number of individuals, that trait became more common. Sometimes it's hard to anticipate whether a trait could evolve to be advantageous. I know in my research, we use genetic algorithms a lot where you have like a population of neural networks, for example, that you're training to do some task.

35:18And something we do a lot is we take a subsample of them and we put them on their own genetic island and we allow them to evolve without competing against the mainland. And sometimes, you know, they do this thing where they have drift, whatever, but they evolve something new and interesting that wouldn't have survived in the first few generations on the mainland, but then comes back and dominates. It's really fascinating. Yeah. So then apply this to Mars. Is the Martian population going to be small enough to have these effects? How big do you have to be to effectively avoid these things? Because I thought Musk is talking about putting a million people on Mars if we're going to take that at face value.

35:51Yeah. So I think what it tells us is that it matters who you send, like who are the founders of a new population makes a big difference. And if you were to choose, say, people that were all fairly similar to one another, right, that would be more likely to set up a scenario where you get genetic drift and random traits becoming more common or disappearing versus the same number of people. But if you have a very heterogeneous, a very diverse set of founding members of the population, then you're less likely to experience genetic drift. So it really matters how you choose the founders. So the size is important, but the composition of the founding population is even more important.

36:38So we shouldn't just send Musk and Elvis friends. Well, what I've said in the book is like what we would want to do, I think, if you're trying to set this, you know, the Martians up for success is you want as genetically diverse a founding population as you can get. You want it to really be representative of as much human diversity as you can. So the way that we've historically chosen astronauts definitely doesn't do that. Right. You sort of screen for the people who are kind of the best of the best, the elite, you know, the right stuff. that whole thing. You would want to do more than that. You would want to also consider, you know, are we representing human diversity as we know it?

37:20And the more diversity, the better. So we can't just bring physicists and biologists. We have to invite the chemists along, you're saying? Oh, no. If there's a gene for being a chemist, then yeah, you probably want to include it. I don't know. We found that gene yet. All right. So the Polynesians were separated for long periods of time, but they never became separate species. And we're going to take a break. And when we come back, we're going to talk about what it might take for people to move to Mars and actually become a different species.

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40:24All right, we're back and we're talking to Scott Solomon, author of Becoming Martian. And on the topic of being a separate species, a friend of mine who's like clearly 100 % white did his DNA testing at 23andMe and it came back that he was 1 % Samoan, which I'm very skeptical of, but he used that as an excuse to never wear sunscreen again. He was like, hey man, I'm Samoan. Oh, no, no, bad choice, bad choice. Yeah. Yeah, but natural selection will wipe that choice out pretty fast, maybe. But I hope not. I hope your friend decides to wear sunscreen. Okay, so the Polynesians were separated for long periods of time, but they never became, as far as we know, we never ended up with separate human species on these separate Pacific islands.

41:11And so, Scott, what does it take to get a separate species? And do you think we'll end up with Martians becoming a different species? And because we have had separate human species on Earth in the past. Yeah, it's interesting. And that was actually part of why I thought thinking about Pacific Islands as an analogy for space is useful because we tend to think of species evolving on islands, right? I mean, the reason Darwin was inspired by visiting the Galapagos Islands and the reason why, you know, biologists like me still go to islands to study evolution is we think that being separated, like physically, geographically separated and living in different environments is kind of a setup for speciation.

41:53So why didn't that happen with the Polynesians? You know, all humans today are the same species. We have some subtle population differences, but nothing approaching the differences between species. So why not? Well, I think there's a couple of things. One is that they weren't actually isolated for very long. So the Polynesians were really the last people to reach habitable specks of land on our planet. Some of the islands that they discovered and settled, like Easter Island, were only settled in like 1200 CE. Like that's like not that long ago in the, you know, the saga of human history. And so they were only perhaps isolated from one another for a few hundred years because as soon as, you know, Europeans started making their way around the Pacific and, you know, having mutinies and whatnot, they, you know, they started moving between islands and creating more connection between them.

42:54Connection. Right. That's right. Well, one of the things I think I said in the book is like, you know, people exchange goods. And when they do that, they also exchange genes. We know that's the case. But actually, to that point, the idea that they were isolated also assumes that once they reach these islands, that that was it, that they weren't then going back and ever interacting with people from either where they came or other islands. And in a few cases, that seems to be the case. Like Easter Island was truly isolated. But for most of the Polynesian islands, people were actually still able to move back and forth and exchange goods and genes with one another.

43:38And, you know, we know this in part from genetic studies, but we also know it from archaeology. There's stone tools that are widely used across the Pacific, but the stone that they used to make them is only found on like a small handful of islands. And yet you see that stone all over the place. They were trading goods, as people do. So, you know, they weren't actually as isolated as you might think. And that's important to recognize because gene flow, the exchange of genes between populations, is another mechanism of evolution. And it tends to prevent speciation from happening. So people might be living far away on Mars, far away from the people living on Earth.

44:22But if people are still moving between those planets and exchanging goods and genes, then it's less likely that speciation would happen. So I suspect that we're going to need resupply ships to keep the Martian settlers alive for a really long time. And I think that will keep gene flow going. But what do you think? Do you think that there will be gene flow happening between the Martians and the Earthlings? Or do you think that something will stop the gene flow? I mean, I think people would probably like to be able to come back to Earth if they're living on Mars. Mars is, as you very well know, is a very harsh place to live.

45:01And Earth is a pretty nice place. So if I was living on Mars, I should want to come visit Earth. But here's the thing. I'm concerned that it won't be as easy as some people have imagined to move between planets. And that's especially true for a child that's born on Mars. For one thing, as their body is growing, they're in one-third G, right, one-third of Earth's gravity. And we know that muscles and bones, they don't develop the same strength when we're in a lower-gravity environment. Now, we don't actually know what happens to a child's growing body in a lower-gravity environment because we've only ever studied adults.

45:42But I think there's a pretty good reason to suspect that a child's growing body would be affected by being in lower gravity. And if they don't build bones that are strong enough to be able to handle Earth gravity, it might be really hard for them to be able to handle being on Earth. So there's the gravity issue. But then there's another problem, which is our immune systems and infectious disease. because we know that a child's immune system develops in response to all of the microbes that we just interact with on a regular basis. And, you know, most of those don't end up being dangerous to us.

46:22But if you're exposed to something that you've never encountered before, then it can be dangerous. And we also know that when we travel, we bring our microbes, our microbiome with us, right? And so people going to Mars will bring microbes that are in and on their body. And we'll probably bring other microbes. I mean, we have to have food. So we're going to bring plants and they come with their own microbes. Every complex organism has a microbiome. But whatever we bring is still going to be a tiny subset of all of the microbial life on Earth. So a child born on Mars will never be exposed to the vast majority of microbes we have on our planet.

47:06So I worry that a child born on Mars who came to Earth would be really at risk of getting sick just from the stuff that isn't a big deal for you and me, but for them might be really dangerous. So then let's assume that there isn't a lot of gene flow back and forth. What are the other selection pressures on Mars that might influence the way humans evolve? You know, the radiation environment, the rotation, the sunlight, these kinds of things. Yeah. So, I mean, we know the gravity is likely to be a big factor, right? We know that being in a lower gravity environment is tough for the body. So I think being in a lower gravity environment is likely to cause natural selection to favor people that have certain traits that make them better at surviving and thriving in that environment.

47:56So one of the things that could happen with adapting to lower gravity is that people might actually be better off if they start off life with denser bones because we expect they will lose bone density as they age. I mean, that's what happens to astronauts. They lose about 1.5 % to 2 % bone density per month that they're in space. And that's in a weightless environment. We don't know if one-third gravity means you lose bone density at a lower rate, but you probably are still losing bone density. So what happens to a person who's born on Mars, has been losing bone density their entire life, and then by the time they go to have kids, you know, a woman who's going through childbirth is now doing that with a weakened skeleton?

48:45That could actually be really dangerous. I mean, childbirth is already dangerous enough, but if you're doing it with a weakened skeleton, it could be really dangerous. And so natural selection might actually favor women who start off life with denser bones so that they're more likely to be able to survive childhood and that their children are more likely to survive as well. So then you'd actually get people with denser bones in future generations. I also thought it was interesting in your book that you suggested that if that ends up being something that like, I don't know, maybe we don't have the genetic diversity available so that we can evolve denser bones.

49:27Maybe we're just going to have to do C-sections every generation because it turns out this will be just way too dangerous. So kids have to be delivered via C-section to save mom. Yeah. And like the implications that could have. I thought that was a really interesting idea. Because we know when we have complications with childbirth, like one of the best things you could do is deliver through a cesarean section, a C-section. And so if, you know, people are having complications with birth on Mars, that might be the go-to. And then if you get to the point where that just becomes the standard, everybody has C-section births, then what are the evolutionary consequences?

50:04Well, at that point, the head no longer has to fit through the birth canal. And that's been a major constraint throughout human evolution. So if the head is no longer constrained to fit through the birth canal, at that point, the head could actually evolve to become larger. So, you know, it's funny because, you know, in one way, it's like kind of sounds like the sci-fi depictions of aliens, right? You know, these big headed aliens. But that's a plausible evolutionary scenario. And in a lower gravity environment, you could hold up that giant head like more easily or something. But then it's hard when you come back to Earth.

50:40So yet another reason why people born on Mars might struggle to come back to Earth. But yeah, we were talking about the radiation environment, and I think that's another challenge because we know that, you know, Mars is bombarded by quite a lot of radiation because it has a very, very thin atmosphere and it has basically no magnetosphere. So, you know, people on Mars, if you're on the surface, you're exposed to, you know, nearly the full force of deep space radiation, galactic cosmic rays and everything else. So, you know, you'd need to have some protection from that just to be able to survive.

51:20You know, maybe we're living underground, but I like to imagine that people aren't going to be content to only be underground. I mean, I don't want to go to Mars if I don't ever get to go, you know, explore on the surface. And, you know, if you're growing crops and doing other activities, you might need to be on the surface. So if people are exposed to higher levels of radiation than we are on Earth, on the one hand, there's cancer risks. But on the other hand, mutation is the ultimate source of genetic diversity. So what you could find is that mutation rates overall are higher, and that's really the raw material for natural selection.

52:00So that's a mechanism by which you could have more rapid adaptation to the environment on Mars because you have basically more raw material for natural selection to work with and then the advantages that would come with any mutation that happens to be beneficial. That's fascinating. I want to underline that. You're saying that radiation itself could be creating the mutations which allow us to survive radiation. Exactly. Incredible. Physics is amazing. But, but what blanket Kelly stepping in here? On average, what aren't most mutations likely to be negative? So aren't like a bunch of people probably going to kick the bucket from cancer and like 1 % are going to like hit the genetic lottery and have like a great mutation that like and 1 % I'm just picking a random number.

52:52I don't that's not like a scientifically justified number. Yeah, probably less than 1%. Yeah, you're right. So this is not a pleasant way forward. We're not talking about like a happy way to see future generations become better adapted, because what you're talking about is a lot of death and suffering. I mean, we're talking about a lot of people having, you know, cancer probably at a younger age, right? You're more susceptible to cancer caused by radiation exposures when you're young because your cells are dividing more rapidly. And every time they divide, there's an opportunity for a mutation.

53:29And death is an essential part of this, right? If people don't die, if they live and have kids, then you don't evolve. That's right. People like to say that, like, physics moves forward one funeral at a time, but so does humanity. That's how evolution works. You know, it's not a pleasant process. And so that's why, you know, one thing that has been proposed is maybe we need to take matters into our own hands, right? Maybe we should be manipulating our genes to try to improve the ability to adapt without having to kind of wait for natural selection, to wait for mutation and then natural selection to discover new ways to do things better.

54:07If we could make those changes ourselves, it would help people by, you know, enabling them to be able to handle the high radiation, low gravity environment, you know, alleviate some of that death and suffering. Wow. Both of our eyebrows just went up because I thought you were going to go another direction and say we should be killing people. Because, you know, we might be like short on resources. And, you know, if we get hungry, we might just have to decide in advance who we think is going to survive. And, you know, some of that flesh could be tasty. I don't know what Martians are going to like to eat.

54:39Daniel got to the cannibalism. It always happens naturally. That's right. That was the perfect transition to genetic engineering. And so then my question for you is, do we know what genes we would need to tinker with? So do we know what we would need to do to people to make them well adapted to the Martian surface? Or at this point, would we just be like making changes and crossing our fingers? I think that we're sort of at the yes and no point. We do know of some of the genes that we might be able to alter. So, for example, tardigrades are famously really resilient and able to survive being in space for long amounts of time, etc.

55:17And we know that they have a gene called DSUP, which stands for damage suppressor. So this is how they're able to suppress damage to their DNA caused by radiation exposure. And so one of the things I did when researching the book was visit Chris Mason's lab at Weill Cornell Medicine in New York, where they're actually taking genes from tardigrades, including D-sub, and cloning them into human cells in culture. And they've been able to show that those human cells actually express the D-sub protein, suggesting that it might be possible to get some of that radiation protection in our own cells. Now, we haven't done that in a living human yet, but if you could do that safely and effectively, that could be really interesting.

56:06So I think we still have a lot of unanswered questions, both about what genes we would want to be editing and also being 100 percent sure that that's not going to have any unintended consequences. Right. And on Earth, we're not comfortable with making those changes in humans ethically yet. So we would also have to, like, decide that we're going to, you know, eschew all of the ethical concerns that we have about making those changes on humans and then decide we're going to go ahead and make them on Martians. What do you think about that? Oh, absolutely. I mean, I think the ethical considerations are enormous.

56:44And I try to, you know, address that a bit in the book. I mean, I think, look, we have a long history of trying to think that we can control our own evolution and that really not going well. I mean, the entire field of eugenics was based on the premise that we could make humanity better by controlling who lives, who dies and who reproduces. And we all know how that turned out. So we clearly don't want to repeat those those sins of our past. But part of what's interesting about this is that the ethics, I think, become a bit different once you're talking about living in this incredibly harsh environment.

57:21So if you had the ability to alleviate death and suffering by making gene edits, would it be unethical to do that or would it be unethical not to do that? But then it gets tricky, too, because it's one thing to agree to edit your DNA knowing the risks. And it's a very different thing to edit the DNA of an unborn child who has no ability to understand the risks and to consent to that. And so, you know, doing a genetic edit to each individual is one thing. doing germline gene editing, which is making changes to the cells that make sperm and eggs that would be heritable changes. At that point, you are manipulating the future evolution of our species and you're making changes to future generations that weren't able to consent.

58:18But aren't you doing that anyway, even if you only edit your own genes? I mean, if I edit my genes to give myself, you know, laser eyes or something, then my kids have laser eyes. And, you know, kids are always brought into the world without consent anyway from the gene pool of their parents. So it depends which of your cells you're editing. So you could make changes to your own DNA that wouldn't be passed on to your kids. So it has to be the cells that make the gametes, the sperm and the eggs. Yeah. Given what you've learned, do you think we should become Martian? So here's the thing. I looked at some of the, like, motivations for why people are trying to do this.

58:58in the first place, which I know, Kelly, you and Zach get into this in your book as well, City on Mars. And I think I came to some similar conclusions as you guys did, which is that eventually, maybe we should. Like, I'm not saying we should never go and live on Mars or any other planet. But I think there's enough unanswered questions such as, you know, is human reproduction even possible? Could a child born on Mars come back to Earth? We need to know those answers before I think we can responsibly start loading people onto ships and sending them out there. But I am kind of convinced by the idea that in the long run, eventually, if we don't do that, we might eventually go extinct.

59:49I mean, there could be a disaster on Earth, And there will be a disaster if you wait long enough, you know, whether it's self-imposed or whether it's an asteroid impact or supervolcano eruption. It's going to happen. The thing that matters is the time frame. So I just don't think we're ready yet. I'd want to see more science, more answers to important questions that we don't know. We could know. We could find out about, you know, human reproductive biology in space. There just hasn't been enough research on it yet. And so that's what I'm saying. We need to do that science. Let's learn. Let's discover.

1:00:28Let's continue doing space science, human space exploration. But let's not start actually living out there until we know we can do it safely. So do you think that this is an issue that species around the galaxy face? You know, if you're an alien now, you're on some other home planet, and you're wondering about hopping to the next planet. Is this a conversation that's being had across the galaxy? Should we be shipping your book to Alpha Centauri? Oh, I'd gladly donate a copy to ship to Alpha Centauri if you know of any missions that are heading that way. Yeah, I think some of the general conclusions of what I'm trying to argue in this book would be applicable to any species living anywhere in the cosmos.

1:01:11I mean, the idea that species adapt to new conditions, the idea that the founders of a population have a big influence on what can happen next, and the idea that it might be hard to move between planets because of how different those environments are and how well-adapted species are to the planet that they came from. Those patterns are going to be true of any kind of life living anywhere. So I think it's really interesting that H.G. Wells, back in 1898, wrote War of the Worlds, imagining a future when sophisticated Martians came and attacked Earth and we couldn't stop them because their technology was too advanced.

1:01:54But what ultimately stopped them? Bacteria. It was the microbes that they had no defenses against that ultimately were their downfall. So I didn't come up with that idea. It's been around since at least 1898. But I think that's actually really prescient. I mean, I think he was onto something that is likely to be a challenge. It's not an insurmountable challenge, but we need to better understand it before we can expect that it'll be easy to move around between planets once we're actually living out there. All right. Well, thanks, Scott, for coming back on the show. Becoming Martian is available in all great bookstores everywhere.

1:02:31And all terrible ones. And all terrible ones, and everyone should run out and grab a copy. Thanks, Daniel. Thanks, Kelly. This is always so much fun to talk with you guys. I appreciate it.

1:02:45Daniel and Kelly's Extraordinary Universe is produced by iHeartRadio. We would love to hear from you. We really would. We want to know what questions you have about this extraordinary universe. We want to know your thoughts on recent shows, suggestions for future shows. If you contact us, we will get back to you. We really mean it. We answer every message. Email us at questions at danielandkelly.org. Or you can find us on social media. We have accounts on X, Instagram, Blue Sky, and on all of those platforms, you can find us at D &K Universe. Don't be shy. Write to us. Aging is real, and so are the benefits of new Vital Proteins Collagen Sparkling Water.

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1:04:04Soon after, I was in their Kohler, Wisconsin foundry, watching molten iron poured, enamel applied by hand, and the beautiful finished pieces ready to ship. Since 1883, Kohler cast iron has been crafted by incredible artisans, and seeing it firsthand gave me a whole new appreciation for their craftsmanship. Now, I'm proud to lend my stamp of approval to my favorite Kohler cast iron products for their durability, beauty, and enduring style. Shop my curated picks at Kohler.com. As the Kohler cast iron ambassador, I say, long live cast iron. Hey, this is Chuck from Stuff You Should Know, and we're submitting our most science-y episodes for your peer review with our new Stuff You Should Know Doing Science Playlist.

1:04:54Out now. You want to know about Occam's Razor? The simplest explanation is usually the right one. We got you covered. Wondered what chaos theory is ever since the first time you saw Jurassic Park? Well, come on down. So distill a nice pot of tea, everybody. Turn down the gas on your Bunsen burner and slip into your most comfortable lab coat and listen to the Stuff You Should Know Doing Science Playlist on the iHeartRadio app, Apple Podcasts, or wherever you get your podcasts. here's something that should not be as complicated as it is getting a racist statue removed and here's something that should be a whole lot easier than it is getting a new one put up in its place i'm akilah hughes and rebel spirit season two is about both of those things as i was watching these statues come down i was thinking about what it meant that i grew up in a majority black city in which there were more homages to enslavers than there were to enslave people listen to rebel Spirit Season 2 on the iHeartRadio app, Apple Podcasts, or wherever you get your podcasts.

1:05:49This is an iHeart Podcast. Guaranteed human.