Why do elephants have such wrinkly skin?

Asked by: Lydia Colebrook, Leeds

The African elephant’s wrinkly skin was recently put under the microscope by researchers in Switzerland. They found that the wrinkles are actually a complex web of ‘microvalleys’ formed as the outermost skin layer (‘epidermis’) thickens and bends with age, causing it to crack.

This fissured skin surface retains five to 10 times more water than a smooth surface, which helps to keep the elephant cool as the moisture (from rain or mud) evaporates from the cracks. Unsurprisingly, Asian elephants have smoother skin than their African cousins, as they live in wetter environments and have less trouble keeping cool.

Read more: 

• Do elephants really never forget?
• How intelligent are elephants?

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