Koalas hug trees to keep cool.


Not only romantic nature lovers love to hug a tree. Also koalas, thecute national animals of Australia, like to snuggle up to tree trunks.

Now Australian researchers have found the reason: The arborealmammals cool down on this way (Biology Letters”, online).

With thermal imaging cameras the scientists discover that the tree trunks – the ones with koalas splayed across them – were much cooler than the surrounding temperature.

Koala Infrared

Using a biophysical model of heat exchange, it was shown that this behaviour greatly reduces the amount of heat that must be lost via evaporative cooling, potentially increasing koala survival during extreme heat events.