Asked by: Josephine Brook, London
It’s a common mistake to look at animals that have not changed much physically over millions of years and conclude that they are somehow less evolved. In fact, evolution has affected them just as much as every other species. It’s just that the forces of natural selection have favoured them sticking to the same design, instead of trying something new.
Humans are certainly still evolving. More recent developments include lactose tolerance, reduced wisdom teeth and blue eyes. And a large genetic study at Columbia University in New York last year found that harmful genetic mutations that reduce our average lifespan are gradually being eliminated by natural selection. But even long life is only an advantage if we have the civilisation and infrastructure to support us all.
There are people with genes that give them an advantage in certain environments – for example, some people are more resistant to tuberculosis. In a densely populated city with poor living conditions, that person would be better adapted and more likely to pass that gene on. But that’s not the same as being ‘more evolved’. If that person moves to a more affluent neighbourhood, or vaccination programs eradicate the disease altogether, then the genetic advantage would disappear.
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