Unlike other apes, humans mostly walk on two feet (Credit: age fotostock/Alamy)

Why we walk on two legs

The real reasons why we stopped moving on all fours

Follow BBC Earth

Earth Capture

Yusef has a close relationship with wild hyenas (Credit: Fredi Devas / BBC NHU 2016)
  1. Yusef has a close relationship with wild hyenas (Credit: Fredi Devas / BBC NHU 2016)
    The man who lives with hyenas
    1
  2. A male Saiga antelope on the vast Eurasian steppe of Kazakhstan (Credit: BBC 2016)
    The beast with an air-conditioning nose
    2
  3. Otonycteris, the desert long-eared bat, lives in the Negev Desert (Credit: Ed Charles)
    Tiny bat hunts deadly scorpions
    3
  4. Glass frog male protects his eggs from a predatory wasp in Costa Rica (Credit: BBC 2016)
    The greatest dad in the animal world
    4
  5. A snow leopard mother and her daughter (Credit: BBC 2016)
    Snow leopards filmed like never before
    5

Unmissable Stories