There are probably more theories on why humans took to walking on two feet than there are suspects in the famous Piltdown Man fossil fraud (over thirty have been suggested, including prominent scientists.) But that’s because the guilty and the innocent all die eventually. Fashionable theories can get reincarnated in a number of different forms Last week, we read that
The researchers say our upright gait may have its origins in the rugged landscape of East and South Africa which was shaped during the Pliocene epoch by volcanoes and shifting tectonic plates.
Hominins, our early forebears, would have been attracted to the terrain of rocky outcrops and gorges because it offered shelter and opportunities to trap prey. But it also required more upright scrambling and climbing gaits, prompting the emergence of bipedalism.
The York research challenges traditional hypotheses which suggest our early forebears were forced out of the trees and onto two feet when climate change reduced tree cover.
Yes, that disputed theory would be the shortage of food in the trees theory, from The History of the World in Two Hours (below).
We’ve also heard that bipedalism developed so we could hit each other. Or carry infants. Or scarce resources. Or save energy. Or cool down. But mainly so we could have our hands free for whatever. (Saving eneregy and cooling down don’t really count here because lots of other methods would have worked; they just wouldn’t have freed the hands at the same time.)
It reminds some of us of questions like “Why did writing (and reading) develop?” Each faction espouses a theory that is only part of the story. If anyone bothered to list all the reasons the development is useful, the discussion would end and no more papers would ensue.
Unless, of course, the development of walking upright occurred quite accidentally, for reasons unrelated to its usefulness, with no one ever even suspecting its advantages. One must be quite the “mind is an illusion” advocate to think that.
See also “I’m Walkin’, Yes Indeed I’m Walkin’” But Not Because It’s Necessarily a Better Way to Get Around
Also, Design perspectives and the physiology of walking