Why Do Elephants Have Big Ears? Cooling and Communication

How do big ears keep an elephant cool?

A large animal makes a lot of heat but has relatively little skin through which to lose it. An elephant’s body has a very small surface area compared with its volume, and it has sweat glands only between its toes. Getting rid of heat is one of its biggest daily challenges, especially in the African sun.

The ears solve part of the problem. Each ear flap is only about 1–2 mm thick in the middle and is laced with a dense network of blood vessels close to the surface. Warm blood flows from the body into the ears, where it gives up heat to the surrounding air. When the elephant flaps its ears, moving air passes over this surface and speeds up the heat loss. The cooled blood then returns to the body.

Elephants control this system. On hot days the blood vessels in the ears widen and ear flapping increases; on cooler days the vessels narrow to save heat. Thermal-camera studies of African elephants show the ears glowing warm when the animals need to shed heat and staying cooler when they do not. Elephants combine ear flapping with other tricks, such as spraying water, wallowing in mud and resting in shade.

Why do African elephants have bigger ears than Asian elephants?

The African bush elephant has the largest ears of any animal, up to about 2 m (6.6 ft) long and 1.5 m (4.9 ft) wide. They reach back over the shoulders and are roughly triangular. The Asian elephant has much smaller, more rounded ears, with the top edge folded over.

The main explanation is climate. African bush elephants live on hot, open savannas with little shade, while Asian elephants mostly live in forest and grassland mosaics with more cover. This pattern, where animals in hot places have larger ears and other appendages, is known as Allen’s rule. The extinct woolly mammoth, which lived in cold steppe, had small ears that lost less heat. The African forest elephant, which lives in shady rainforest, has rounder ears than the bush elephant. For more differences, see African vs Asian elephant.

Do big ears help elephants hear?

An elephant’s outer ears help collect sound, and elephants have excellent hearing for very low sounds. Many of their own calls are infrasonic rumbles, below the range of human hearing, which can travel several kilometers. Their middle ear bones are adapted for these low frequencies.

Elephants can also detect vibrations through the ground, picking them up through their feet and leg bones. When listening this way, they sometimes lean forward and freeze. Learn more in How do elephants communicate?

How do elephants use their ears to communicate?

Ears are also an important part of elephant body language. An elephant that wants to look threatening raises its head and spreads its ears wide, making itself look even bigger. It may shake its head so the ears slap against its body, or flap them loudly. Many of these displays are bluffs designed to warn off a rival or predator.

Excited elephants also hold their ears out, for example when greeting relatives after a separation. A submissive elephant does the opposite, holding its ears flat against its neck. For people on safari, spread ears, a raised head and a raised trunk are signs to give the animal more room.

Other uses of elephant ears

Ear flapping helps drive away flies and other biting insects. Elephants also throw dust and mud over their bodies and behind their ears for protection from the sun and insects.

The edges of elephant ears pick up tears, holes and notches over the years, and the pattern of veins is visible on the back of the ear. Researchers use these marks, along with tusk shape, to recognize individual elephants in long-term studies, such as the one in Amboseli National Park, Kenya, which has followed thousands of known elephants.

Myths about elephant ears

A common claim is that an African elephant’s ears are shaped like the continent of Africa, and an Asian elephant’s like India. It is a handy memory aid, but it is a coincidence, not a rule; ear shape varies between individuals. Another myth is that elephants can fly with their ears, which comes from Disney’s 1941 film Dumbo. Real elephants are far too heavy, and their ears are for cooling, not lift.