The reason elephants have giant ears

African elephants (African Loxodonta) is the world’s largest land mammal and has the largest ears of any modern elephant. In fact, they are so large that they take up 20% of the total body surface area, according to the study IFL Science.

The mechanism behind the massive shape of elephant ears is temperature. Normally, elephants will roam about 25 km a day, but they can travel up to 190 km if they want. Their wanderings mean they will encounter diverse environments, from high grasslands to jungles, but the hottest places are deserts and arid regions. Their optimal body temperature is 36 degrees but temperatures here can be much hotter.

Large ears are how elephants have evolved to maintain body heat when environmental conditions heat up. Such a structure allows more blood vessels to lie on thinner skin areas, making it easier to radiate heat. Such a large yet thin part also results in a larger surface area, providing more opportunities to radiate heat. It is estimated that African elephants can circulate about 12 liters of blood around their ears every minute.

Comparing the giant ears of African elephants with polar bear ears, we will see the same scientific mechanism. Through much smaller ears than other bear species, polar bears are able to conserve heat, as opposed to African elephants that need large ears to cool down.

However, African elephants do not top the list of largest ears when compared to body size. That title belongs to the long-eared jerboa (Euchoreutes naso). This desert creature has ears that are 1/3 longer than their head. Native to the deserts of southern Mongolia and northwestern China, they also need oversized ears to maintain body heat. The long-eared jerboa also adapted to the desert environment by evolving kangaroo-like legs.