Geneticist contends human evolution may be grinding to a halt
The Press Association (10/7) reports that Professor Steve Jones, of the University College London, says that "human evolution is grinding to a halt," adding that "this is as good as it gets." In fact, he "believes the mechanisms of evolution are winding down in the human race." Jones explained that "there were three components to evolution — natural selection, mutation, and random change." He added, "In ancient times half our children would have died by the age of twenty," but "our life expectancy is now so good that eliminating all accidents and infectious diseases would only raise it by a further two years." Thus, "natural selection no longer has death as a handy tool."
Furthermore, according to Jones, "human social change often changes our genetic future," the U.K.’s Times (10/7, Belluz) adds. While "chemicals and radioactive pollution could alter genetics, one of the most important mutation triggers is advanced age in men." Jones pointed out that "every time there is a cell division, there is a chance of a mistake, a mutation, an error," and "for a 29-year old father [the mean age of reproduction in the West], there are around 300 divisions between the sperm that made him and the one he passes on." But "a drop in the number of older fathers will thus have a major effect on the rate of mutation."
The "third factor – randomness — is also an important ingredient in evolution," as "small populations which are isolated can change at random as genes are accidentally lost," the U.K.’s Daily Mail (10/7, Derbyshire) notes. Yet, "as the world’s population becomes increasingly connected, the opportunity for random change is dwindling." Jones concludes, "So, if you are worried about what Utopia is going to be like, don’t. At least in the developed world, and at least for the time being, you are living in it now."
Comments (1)
EM
He forgot the most obvious danger to human evolution : over the past two generations, the poor and stupid have been reproducing much faster than the rich and smart, in total opposition of the preceding millenia and to all the Darwinian rules. Worse, fertility clinics are now turning infertility into a familial disease.
Which is why we should grow out of our fear of genetic modification and take control of our evolution before the gene pool turns bad.