After scientists map a species' genome, they compare it to the genetic maps of other species. As they do so, they search for key differences that involve duplications, deletions and inversions of genetic material. These differences may contribute to the unique features of particular species. They may also provide information about general evolutionary trends, such as the overall rate at which genomic evolution has occurred.
Before the orangutan's genome was mapped, the genetic codes of three other great primates--humans, chimpanzees and rhesus macaques--were mapped.
The genomes of the gorilla and bonobo will soon be mapped, as well.
Analyses of the orangutan genome reveal that this primate has many unique features. For example, comparisons of the structural variation of the genomes of orangutans, humans, chimpanzees and rhesus macaques indicate that during the last 15 million years or so of primate evolution, the orangutan genome has generally been more stable than those of the other primates, with fewer large-scale structural changes.
The orangutan genome also allowed for an analysis of fast-evolving genes, which are likely to have responded to evolutionary pressure for adaptation. Genes related to visual perception and metabolic processes were found to evolve unusually rapidly in orangutans and other primates. The orangutan's metabolism-related genes were also found to have evolved rapidly--a phenomenon that may be related to the organgutan's slow growth rate, slow reproduction rate, and long inter-birth interval, the period between successive births. Organutans give birth not more than once every six to eight years, an inter-birth interval rated as the longest among
|Contact: Lily Whiteman|
National Science Foundation