How to Beat the Heat

Endotherms and ectotherms have various ways to keep from getting too hot. One way is sweating. Endotherms sweat to keep their bodies from overheating. When you sweat, heat moves outside your body as water. As the water evaporates, you cool down.

Most endotherms don’t have sweat glands. Yet, they have other ways to cool down. Dogs pant. With each breath, moisture evaporates from their tongues.

Dogs don't sweat. Instead, they pant to cool down.  

Many animals use their ears to beat the heat. An elephant’s large ears have many veins. Heat from the warm blood moves through the thin skin into the air. Cooled blood then circulates through the body.

This kangaroo licks its arm to keep cool. 

This fennec fox uses its big ears to cool down. 

Kangaroos lick their forearms to cool down. It’s a little gross, but it works for kangaroos. Ectotherms can overheat, too. Some lizards burrow into the ground to keep cool.

This iguana burrows into the soil to cool down. 

How to Turn Up the Heat

Ectotherms such as reptiles sometimes burrow into the ground for another reason. When the weather turns cold, they hibernate.

This walrus’s layers of blubber help protect it from the cold.  

Endotherms like birds and mammals turn up the heat by shivering. The brain signals muscles to vibrate. This produces heat to warm the body. Some ectotherms, like bees, shiver, too.

Many endotherms have hair, fur, or feathers that keep the cold air out and the body heat in. Marine mammals grow thick layers of fat called blubber.

Endotherm vs. Ectotherm

So, which animals have the advantage to survive? If a snake was trying to catch a mouse on a cool day, the mouse probably has the advantage.

However, the snake needs a lot less food than the mouse does to survive.

Endotherms can live almost any place on Earth. Most ectotherms can only survive in warm and mild climates. It’s hard to say which has the upper hand. Looks like both have ways to survive in their environment.

A mouse is an endotherm. A snake is an ectotherm.