Under extreme heat, squirrels sploot

JUANA SUMMERS, HOST:

So Ari, I've got to say, it is hot outside.

ARI SHAPIRO, HOST:

Ugh. Try riding your bike in a suit. And we don't even have the worst of it. Just south of here in Washington, D.C., places in the U.S. are under heat advisories as temperatures break 100 degrees. Millions of people are facing dangerous extreme heat.

SUMMERS: Yeah, I mean, we had some good tips on the show yesterday for staying safe and comfortable in heat like that, some of which may feel kind of obvious, like staying as cool as possible by hydrating and trying not to run around too much.

SHAPIRO: Yeah, but there's one thing we didn't mention, which is splooting.

SUMMERS: Splooting - that is a very silly word for a pretty cool strategy, something animals do more than humans. Walk around on a hot day, and you actually might see a squirrel splooting.

ANDREA RUMMEL: I think it's called splooting 'cause that is kind of what it looks like. It's like if a squirrel just, like, splattered down on the pavement. All of its limbs are splayed, so it's kind of like spread-eagle on the ground.

SHAPIRO: That's animal physiologist Andrea Rummel. When humans are hot, sweating cools us down. But she says animals that can't sweat have to resort to other behaviors to cool off.

SUMMERS: The squirrels are trying to regulate their body temperatures by spreading out on a cool surface. Think of it like finding the cool part of the pillow when you're trying to fall asleep.

SHAPIRO: And it's not just squirrels that sploot. Dogs, raccoons, bears - all kinds of animals will do it if they are overheating.

SUMMERS: Carlos Botero, an associate professor of biology at the University of Texas at Austin, says that, while it might look kind of cute, it's actually a sign that they're under a lot of stress.

CARLOS BOTERO: The temperatures that we're experiencing right now are a little bit beyond the typical ability of these animals to withstand.

SUMMERS: And climate change is making things even harder for squirrels.

BOTERO: These extreme conditions are becoming more and more common. So until, somehow, the physiology of squirrels gets adapted to the new normal, they will have to do this extra behavior to try to cool themselves off.

SHAPIRO: The animal physiologist, Rummel, says splooting is enough to keep the squirrels cool for now, but...

RUMMEL: For every kind of thermal regulatory mechanism, there is a point at which it doesn't work anymore, and that depends on environmental temperature. So it's going to get harder and harder for squirrels to sploot effectively as temperatures rise.

SUMMERS: So if you're experiencing some of these extreme temperatures, keep your eye out for splooting squirrels. Then, head inside ASAP for some ice water and AC.

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