Short Wave - How hurricanes triggered lizard evolution

Episode Date: September 8, 2026

Hurricane season is upon us and it turns out that these powerful storms can quickly affect the biology of animals. After hurricanes Irma and Maria hit the islands that make up Turks and Caicos about a decade ago, the silver key anole adapted. They now have a shorter fourth toe on their hind legs! That could help them cling to objects better. But how do you know unless you put lizards in front of a fan and record how long they can hold on?This study is out now in the journal Current Biology.Interested in more science in the news? Email us your question at [e-mail] public media with NPR+ and enjoy perks for over 25 podcasts like this one. This show’s perks include sponsor-free listening. Learn more at plus.npr.org. See pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences.NPR Privacy Policy

Hey, Regina Barber here to ask if you'll follow Shortwave on the NPR app or whichever one you're using. It's a little action that goes a long way for our small team. Okay, here's a show. You're listening to Shortwave from NPR. Hey, Shortwaver's Nate Rot here with my co-host, Gina B. Hey, Nate. We are back with our biweekly science news roundup with Friend of the Pod and West Coast best coast host of all things considered. Elsa Chang. Hi, hi, hi,

West Coast is the best coast. West Coast, best coast. I used to think that. But yes, for this small amount of time, I will think that again. Thank you, Gina. So, Elsa, you remember the last time we gave you a kind of difficult science quiz? Yeah, I failed like every question. Well, wasn't everyone?

I've got great news. Yeah. We've got another one. But this time, hey, we're going to make it easier. We're going to make it multiple choice. And there's going to be a fact that relates to each of the science news stories that we're covering today. You ready? I'm so ready.

Okay, so our first topic is pretty relevant to this time of year. We're in hurricane season, right? Yeah. Started in June, usually last through November. And there are lizards in the Caribbean that have adapted to better survive those hurricanes. So weird, but okay. So this is my question. What is that kind of adaptation called?

Is it, A, climate resilience, B, reptilian progression, or C, rapid evolution. Ooh. Climate resilience? It is rapid evolution. It's okay. We got another one. We got another one. Keep going. Okay.

So our second story is about verifying ancient artifacts, specifically pottery. But I'm wondering, if you happen to know, Elsa, how old are the oldest pottery pieces archaeologists have ever discovered? Is it A, thousands of years old? B, tens of thousands of years old Or C, only a couple hundred years old Okay, I know it's not C, it's between A and B, how long have humans been around? I'm going to just say thousands of years old, that's A.

You were doing so good. You were so close. Tens of thousands. But your process of elimination, we're getting closer. Okay, so our last story is not one to make light of because it's actually kind of serious. It's about the effects of extreme heat on the human body which of these following conditions make it more likely for someone to get heat stroke?

Is it A, lightning strikes, B, a high UV index, or C, increased humidity? Ooh, well, it's not a lightning strikes. It's either higher UV or higher humidity, but I'm going to go with higher UV. You're so close. We want you to succeed. We really do. Humidity is a really important fact. in heat stroke risk because if it's so humid that your sweat can't evaporate off your skin,

then it's pretty easy for the human body to overheat. So in my brain, I was thinking higher humidity would help me dehydrate less. But you're telling me it makes you dehydrate more. Yes. Yeah, it's pretty bad. We learn from our failures. Well, let's take that failure and let's launch into the success of the rest of this show. We've got lizards that survive hurricanes. Plus a new method of dating ancient pottery.

Not dating like going on a date with them. No. Telling people how old they are. Right. Yeah. At this point, I'll try anything. Oh, no. And we'll talk about some surprising health issues that could be linked to extreme heat.

You're listening to Shortwave, the science podcast from NPR. Okay, Elsa, I'm going to start us off with lizards. Okay. You mentioned that they were evolving because of hurricanes? What? Yes. So this story is set on these two islands in the Caribbean. These islands were walloped by hurricanes Irma and Maria about a decade ago.

And researchers wanted to understand how these hurricanes might have affected populations of lizards that live there. They're called Silver Key and Knowles. And in particular, they wanted to know why the surviving lizards from these hurricanes seemed to have shorter fourth toes on their hind feet. Shorter toes on their hind feet. What's up? Well, the researchers think that these shorter toes are. might have given the lizards a selective advantage during these hurricanes, where they endured these incredibly strong winds.

Yeah, it's physics. It turns out the shorter toe gives the lizard more leverage to hold onto the branch better than a longer toe. And at Princeton University, evolutionary biologists tested this out. They put lizards in front of a fan to simulate tropical storm force winds. Oh, my God, poor lizards. Yeah, we asked one of the researchers, Shane Campbell, Staten, if the lizards seem annoyed by this?

They are as annoyed as you would expect from, you know, somebody blowing a bunch of wind in your face. You know, but the trials themselves are actually very short. Annette catches them. So the lizards were totally fine. And it turns out that the lizards with the shorter toe were able to cling on for a half a minute longer than ones with longer toes. But what's really cool about this study

is that researchers were able to confirm a specific gene that was linked to making these toes shorter, like showing that these hurricane force winds likely shaped the genes of subsequent generations of these lizards, something they wrote about recently in the journal Current Biology. So, like, why did these scientists even get obsessed in the first place about the toes of these lizards? Well, so by teasing apart all the genes at play here in follow-up research,

they're hoping that it'll give geneticists a deeper understanding into how, you know, multiple genes interact with each other and the environment to drive change. and animals, and it could help researchers understand how other animals might be able to adapt to rapid changes in the future. Ah, okay. All right, from lizards to artifacts? Yeah. Let's go.

Yeah. Okay, so this study is looking specifically at clay artifacts like pottery figurines, which, Elsa, if you've ever been to a museum, you know they hold a pretty important significance in human history. Yeah. And one of the issues that museums and law enforcement agencies face today is that people will, sometimes sell forged or fake clay antiquities. Yeah, like they'll claim a piece of pottery or some figurine is thousands of years old when it's totally not. Yeah, exactly, Elsa. And to be clear, this isn't new.

There was fraud of statues already in the Roman period. So it's something that goes back a long time. That's Yuave Vaknan. He's a postdoctoral student at the Scripps Institution of Oceanography and the lead author of this new study, which describes a new way to determine whether something is legit or not. Interesting. Okay, tell us how this works. Magnetism, Elsa. It's physics again. Yeah.

So when you take a piece of raw clay and you put it in a kiln, the iron-bearing minerals and that clay will align with the Earth's magnetic field. Whoa. Kind of like you can imagine a needle of a compass, but on the atomic level. And when that clay starts to cool, the larger particles get locked into that position, creating kind of a permanent record of the Earth's magnetic field at that moment. Wow. So it's like unique to that particular time. in place on Earth? And scientists can use that data to date the pottery? Unfortunately, no, because the objects have moved from their original position. But there are these smaller particles that don't get locked into position. And their magnetic signatures never really

settle. So they move with the Earth's magnetic field over time. Yeah. And the secondary magnetic signal can be erased by reheating the object. And what Yoave and his colleagues discovered is that it takes hotter temperatures to erase it in old objects than it does in new. Huh. Okay, so you could theoretically test to see if an object is old or authentic versus new and forged just by reheating it? Yeah, they tested old artifacts, and they found that if it takes above 112 degrees Celsius to erase that secondary magnetism, the object is indeed more than a thousand years old. Now, I will say also you need very specialized equipment to do this, but the method described in the proceedings of the now, National Academy of Sciences could be used by museum curators or others to determine if artifacts are indeed legit in the future.

Well, speaking of heating or reheating, let's get to our final topic. Let's talk about these health issues linked to extreme heat. Yeah, more on the serious news here. We know that climate change is linked to more frequent and more severe heat waves, but we still don't know the full impacts of those heat waves on human health. So researchers in Chicago analyzed almost a million ER in urgent care visit. over the past 12 years. And they did this to find which diagnoses were correlated with periods of extreme heat in the city. Basically going in without a preliminary idea of what they're looking for, just running through

the data and looking for patterns. Yeah, and what they found wasn't just like your typical culprits from heat like dehydration or heat stroke. Really hot days were also associated with things like higher diagnoses of kidney failure, of skin rashes, of swelling, of mental and behavioral disorders, assault and Elsa, even traffic accidents. I mean, I feel like that kind of makes sense because when it's really hot, people kind of go out of their minds, yeah? I mean, yeah, totally.

So, like, researchers told us that, like, some of these more mental and behavior-related diagnoses, they might be due to heat stress. Like, let's listen to one of the researchers on this project. We do know from prior literature that when it's hot out, people are under a lot of stress, mental, physiologic stress. People are out more, and behaviors change. So that's Dr. Abel Co. He lives in Chicago where he's a professor of medicine at Northwestern University as well as a practicing physician. And he was part of the team that did this research. They recently published a paper with these findings in the journal Science Advances. Okay. Got it. So now that they've found these associations, what do you do with them? So Abel and the other experts we talked to said it's important to note that these are looking at associations, not causality. Maybe that's the next step, like figuring out why Extreme Heat might exacerbate these. health issues and how to deal with it.

And Elsa, I want to just plug really quick. Speaking of extreme heat studies, NPR climate correspondent Alejandra Burunda, has been working on a huge project with Boston University scientists to investigate undercounted heat-related deaths across the country, and it's really enlightening. So you can search for your county and track the number of heat-related deaths near you on the NPR website. We'll link to it in the show notes. I highly encourage people to go check it out.

I'm going to check it out. Yeah. Well, Elsa, thank you, as always. of course. For kicking it with Shortwave. You're the best. You guys are so much fun, even when you humiliate me. No.

No. Thank you for coming. So if you, like me, love having as much Elsa in your life as possible, check out, consider this. NPR's afternoon podcast about what the news means for you. This episode was produced by Hannah Chin and Mark Rivers. It was edited by Rebecca Ramirez and Christopher in Taliazza. Tylerada. Jim E. Keele and Aowen, is it fan?

Fan? Or is it Fane. Fane. Fane. A.O. and Fane. Like we're feigning. Okay. Tyler Jones and Tyler Jones checked the facts. Jimmy Keeley and Aowen Fain were the audio engineers. I'm Regina Barber. And I'm Nate Ratt. Thanks for listening to Shortwave, the Science Podcast from NPR.