For prehistoric people, 2 legs are better than 4

Standing up costs less energy than " walking ", which is equal to the elbow. This finding explains why human beings today, unlike other primates, walk on two feet.

In the study of "The motive energy of chimpanzees and the origin of the mechanism of human legs ", scientists hypothesize that walking with two feet (or upright) is evolved because it requires less energy. more than the creeping cow with all four limbs.

"For decades, researchers have now considered the role of energy and the evolution of bipedal," said one of the team leaders, assistant professor David Raichlen from the University of Arizona. , USA, said.

The group used " biological mechanism modeling" to simulate this primitive gait. The group also looked at the walks of four adults walking on an exercise machine, and studied five trained chimpanzees to walk on four feet, as well as walking on two feet.

Raichlin and colleagues found humans walking on their legs using only 1/4 of the energy compared to chimpanzees walking on their elbows.

Bipedal walking is considered the most important evolutionary distinction between humans and other human primates.

T. An