Humans shed hair to run faster and longer: Study

For a cool head

This meant that they could run faster for longer and bring home the bacon, the Daily Mail reported. The difference between humans, with their lack of body hair, and other mammals has baffled zoologists for decades, but the new research will help settle the matter, said Dr David Wilkinson of Liverpool John Moores University.

He said: “Most major western art galleries contain paintings or sculptures of the human nude, yet viewed through the eyes of a zoologist rather than an art lover these representations show remarkably odd animals that have lost their body hair and walk upright.

“Our computer model means we can investigate the theory that human body shape is an adaptation which allowed our ancestors to run for long distances in hot conditions.

“It suggests that although the earliest upright humans may well have walked from place to place or run short distances – perhaps to a tree to escape predators -- they could not run long distances to catch their supper. “Humans are unusually sweaty mammals and our results show just how important sweating rates are in allowing long-distance running in the tropics.” The idea that we lost our hair to keep cool on the hot African savannah was first proposed in the 1980s by Professor Peter Wheeler, also of Liverpool John Moores, using a series of mathematical models.

However, his calculations were done on a programmable electronic calculator which was not sophisticated enough to take into account the impact of running on early humans’ thermal ecology.

According to the fossil record, humans began to walk on two legs some four million years ago, but they cannot say when we first started to lose hair as it doesn’t fossilise. Dr Wilkinson estimates that it was probably around three million years ago, when public lice were first thought to have appeared.

To get a definitive date for when we started becoming smooth skinned, we would need to find one of our ancestors buried in volcanic ash, which is known to preserve hair, he explained.