Science and Health

Koalas Hug Trees To Keep Their Cool, New Study Says

A new study out from the University of Melbourne says koala bears hug trees to stay cool during hot weather.

Koalas Hug Trees To Keep Their Cool, New Study Says
Flickr / Tim Williams

Ever wonder exactly why koalas hug trees? Well, aside from it being incredibly adorable, a team of researchers from the University of Melbourne says it serves an important purpose.

"Apparently, they hug the lower parts of the tree because that's where it's cooler. And they somehow are able to pass off some of their body heat to the tree." ​(Via HLN)

In a new study, scientists found koalas move to lower parts of trees in hotter weather to keep cool. The researchers found they even press their bodies closer to the trunks to get the maximum benefit. (Via Biology Letters)

The team made these observations while studying 30 koalas in Melbourne, Australia, during a few particularly hot summer days.

The BBC reports the scientists used a thermal camera mounted on a long pole up in the trees to measure the temperatures the koalas were feeling.

The researchers found in the hotter summer weather, the koalas would move down the trees instead of staying up high near the leaves. (Via National Geographic)

One of the study's authors told the BBC"They'd just flop over the [lower] tree trunks. It looked like they were spread-eagled and uncomfortable; it seemed like the wrong thing to do."

But after comparing the temperatures of the tree trunks and the koalas themselves, the researchers discovered the animals that hung out near the bottom of the trees were up to 7 degrees cooler than the air. (Via Flickr / Cathy)

The Huffington Post quotes one of the study's authors in a statement summing up their findings. "When we took the heat imagery it dramatically confirmed our idea that 'tree hugging' was an important cooling behavior in extreme heat. Cool tree trunks are likely to be an important microhabitat during hot weather for other tree-dwelling species, including primates, leopards, birds and invertebrates."

So why don't koalas beat the heat by panting or licking their fur, like other mammals do?

The researchers told The Guardian doing that could leave the koalas dangerously dehydrated. Koalas don't have sweat glands, and during times of high heat and low rainfall, the animals simply can't endure the evaporation caused by panting or licking.

Well, no wonder koalas love to hang out in trees, then! The study was published Wednesday in the journal Biology Letters.