Tree-dwelling humans were first to start walking upright

HUMANS learned to walk upright in the trees, not on the open land, experts said yesterday.

The new theory marks a U-turn in scientific thinking. Previously it was assumed humans only began to stand upright after moving out of the forests onto the wide open savannahs of east Africa.

Moving on two legs was thought to have evolved slowly from the all-fours “knuckle-walking” displayed by chimpanzees and gorillas today.