I retweeted an article recently that showed that UK citizens have been getting taller over the last hundred years or so, commenting that somehow I seem to have got stuck at about 1900. Then someone replied that scientists reckon the human race became shorter after it started farming. All this got me thinking on the question of are we humans still evolving and if so how?
Now classically evolution is about species evolving to better survive in a changing environment or to fill a new niche. Extinction can arise when the environment changes rapidly and highly specialised species don’t have time to adapt. The difference with the human race of course is that for about the last 10,000 – 20,000 years we’ve changed the environment to suit our needs. So the I guess there is little or no pressure on us to evolve.
However, even without GM, we humans have tinkered with the ‘evolution’ of other species, ever since we domesticated them, through selective breeding. You only have to look at old paintings of sheep and cattle to see how different they are to modern animals. What’s more this tinkering produces notable changes within a relatively short period of time. So are we doing the same to the human species without knowing it? For example do tall people tend to take up with tall people and produce even taller children? Could we end up with a race of really tall people and a race of ‘little’ people (that’s not leprechauns by the way)? Now you might ask is there any evidence for this? Well I’ve not seen any, but then has anyone looked? Also I might argue that until recently (the last century or so) the drivers for finding a partner were different. The choice perhaps more limited. People tended to marry etc. more within social class or with those in the same community. This is much less so now, therefore opening up the possibilities I allude to, as with tall people.
So could we be generating sub species without knowing it? Do musicians tend to have children with other musicians who then have musical children?; what about athletes?; the super intelligent? i.e. will we produce subspecies specialists within the human race? Perhaps even within just a few hundred years. Only time will tell.
I’m sure some of you will have counter arguments , I look forward to seeing them. Or you might have a favourite subspecies you would like to see?