Process separate from natural selection also drives human evolution

Washington, Jan 27 (ANI): A new research, led by a group at Uppsala University in Sweden, has suggested that apart from natural selection, a separate neutral (nonadaptive) process has also made a significant contribution to human evolution.

The researchers identified fast evolving human genes by comparing our genome with those of other primates.

However, surprisingly, the patterns of molecular evolution in many of the genes they found did not contain signals of natural selection.

Instead, their evidence suggests that a separate process known as BGC (biased gene conversion) has speeded up the rate of evolution in certain genes.

This process increases the rate at which certain mutations spread through a population, regardless of whether they are beneficial or harmful.

"The research not only increases our understanding of human evolution, but also suggests that many techniques used by evolutionary biologists to detect selection may be flawed," said scientist Matthew Webster.

BGC is thought to be strongest in regions of high recombination, and can cause harmful mutations can spread through populations.

The results lead to the provocative hypothesis that, rather than being the result of Darwinian selection for new adaptations, many of the genetic changes leading to human-specific characters may be the result of the fixation of harmful mutations.

This contrasts the traditional Darwinistic view that they are the result of natural selection in favour of adaptive mutations. (ANI)