Awesome Animal Fact - Cool Kangaroos

Did you know kangaroos cool themselves by licking their arms? Many kangaroos in Australia live in extremely hot places, often over 100 degrees Fahrenheit. In these conditions, large mammals can have a hard time keeping their core body temperature from getting too hot. Many mammals, like humans, moderate their temperature by sweating.

Kangaroos are unusual in that they sweat when they are hopping (the kangaroo version of running), but when they stop hopping, they stop sweating and switch to panting instead. They pant at up to 300 breaths per minute, which keeps air flowing through their windpipe to cool their interior.

But sometimes this isn't enough, which is when kangaroos start licking their forearms. Kangaroos have special networks of densely packed blood vessels just under the skin of their forearms. When they moisten their arms by licking, the saliva evaporates, cooling the skin, which cools the blood just below the skin. This cooled blood then travels throughout the rest of the body, cooling the entire kangaroo. Cool, huh?

Photo Credits:
- Kangaroo licking arm - M Kuhn via Flickr (Creative Commons license CC BY-NC-SA 2.0)