One of the most important questions for evolution researchers is how a species develops and adapts during the course of time. An analysis of the genes of 12 chimpanzees has now demonstrated that the chimpanzee X chromosome plays a very special role in the animal’s evolutionary development. The analysis was carried out by researchers at the Bioinformatics Research Centre, Aarhus University, the Section of Bioinformatics, University of Copenhagen, the Copenhagen Zoo and the sequencing centre at the Beijing Genomics Institute (BGI), China.
The background for evolution is found in our genome — in DNA. Evolution is driven by mutations that create changes in the genome on an ongoing basis. These mutations are most often deleterious, but they are sometimes beneficial for bearers in the environment in which they live. Their survivability can be improved, which in turn increases the likelihood of having more offspring. These beneficial variants then increase in number until all the individuals in a species have the new variant. This process is called natural selection.
More here Chimp ‘X factor’