If you’re reading this, we can be confident of one thing. The chances are 90% that you’re right-handed. And of one other thing: they are 10% that you’re left-handed. when you think about it, this fact is so woven into our everyday lives that we take it for granted-in work, in sport, art-well, everything. And it seems to be very old. Our Neanderthal cousins showed exactly the same ratio.
So, if such a pesky thing as handedness exists at all, you’d expect our nearest relatives, chimpanzees, to show exactly the same pattern, right? Wrong. Chimps do indeed show hand preferences. But give and take a few donnish arguments among researchers, they seem to come out somewhere around 50% right and 50% left. They certainly don’t show this strong, settled right-hand bias that the human line has preserved. Counter-intuitive, isn’t it?
So, why? It’s a very big question. Any answer has to be hypothetical, as the trend must have started millions of years ago. Hannah Fry makes a good first stab it here[1] for the BBC. But there is one other possible reason. Humans spend a lot more time standing up than chimps do. And this frees the hands for several things. Carrying. Signalling. And making tools. Now, as Sverker Johannsen [2] points out, the parts of the brain that control language is on the left side of the brain. And by the simple fact of the way we’re wired up, that controls the right hand. Is it possible that this handedness thing is in some way connected to the use of tools, or language, or even both? We await new discoveries with anticipation.
[1]https://www.bbc.com/future/article/20160930-the-mystery-of-why-left-handers-are-so-much-rarer
[2]The Dawn of Language; How we came to talk by Sverker Johannsen , translated by Frank Perry Maclehouse Press 2021
#evolution #tools #language #left hand #right hand
Learning, Science and Society 