Dr. Eggman (932300) writes "Ars Technica reports on an interesting new study that suggests not only that certain areas of the mouse genome undergo more changes, but that changes to those areas are more tolerable by the organism than changes in other areas. Recently published in Nature Genetics, the study examined the certain copy number variations of the C57Bl/6 strain in mice that have been diverging for less than 1,000 generations. The results were a surprising number of variations that arose in the short amount of time as well as the notable number of times certain regions were affected. Of the 38 CNVs they looked at in detail, 18 arose more than once, and 10 of those underwent copy number changes more than twice. While the study does not address it, Ars Technica goes on to recount suggestions that genomes evolved to the point where they work well with evolution. That organisms with certain genes, that in specific doses will affect an organism's ability to adapt to environmental changes, may be selected because those genes appear in regions of unstability and therefore give it a faster adaptability rate."