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  • As if koalas could be any more adorable than they already are, they tend to spend a lot

  • of their time hugging trees.

  • Now I get living in trees- that’s a good way to avoid predators since larger animals

  • usually can’t climb them.

  • But there's plenty of animals, like most monkeys, that live in trees, and they don’t feel

  • the need to hug them all the time.

  • And for a long time, zoologists weren’t sure why koalas felt the need to wrap themselves

  • around the tree so much.

  • And yeah maybe this doesn’t sound like the most pressing scientific question, but according

  • to a new research study, theyre actually hugging the trees to stay cool.

  • Australia is not one of the most hospitable of places to live. It’s really hot a lot

  • of the time, there’s not much water around, and food can be hard to come by.

  • So koalas have to keep cool somehow, but they have a big problem: they don’t sweat.

  • Now, koalas aren’t the only animals that can’t sweat. Dogs, for instance, can only

  • sweat through the parts of their bodies that aren’t covered in fur.

  • To keep cool, dogs lick their noses and pant. Kangaroos do the same thing, they lick their

  • forearms. The extra heat they lose through the moisture cooling on their skin is usually

  • enough to regulate their body temperatures.

  • But when it gets unusually hot and there isn’t much rain, koalas would rather not lick themselves

  • or pant, because they’d get dehydrated too quickly. And when you live in a tree, water

  • can be hard to come by. Climbing down to find water would expose them to predators, so they

  • don’t want to do that.

  • In fact, koalas don’t normally drink very much; instead, they usually get all the water

  • they need from the eucalyptus leaves they eat.

  • By hugging trees, though, koalas can stay cool without losing water.

  • When researchers took infrared pictures of the koalas hugging trees, they realized that

  • the trees are, on average, about five degrees cooler than the surrounding air.

  • Theyre not sure why the trees are so much cooler, but they think it might have something

  • to do with the groundwater the trees pull up through their trunks.

  • But it might also just take longer for the trees to heat up after the cool of the night.

  • By spreading as much of their bodies as possible against the trees, koalas are able to transfer

  • away some of their heat, and can cool themselves down by as much as 68 percent.

  • So yeah, hugging trees is adorablealso useful.

  • Thank you for watching this SciShow Quick Question, and especially thank you to 7-year-old

  • Zahava from Minnesota who suggested this topic. If you have questions you would like answered,

  • you can find us on facebook, tumblr, and twitter and, of course, in the comments below.

  • And if you want to keep getting smarter with us, just go to youtube.com/scishow and subscribe.

As if koalas could be any more adorable than they already are, they tend to spend a lot

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B1 US hugging lick stay cool sweat water pant

Why Do Koalas Hug Trees?

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    Eating posted on 2015/02/24
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