Slow Molecular Clocks in Old World Monkeys, Apes, and Humans

摘要: Two longstanding issues on the molecular clock hypothesis are studied in this article. First, is there a global mammals? Although many authors have observed unequal rates of nucleotide substitution among mammalian lineages, some proposed for all eutherians, i.e., single rate 2.2 x 10(-9) substitutions per site year. We reexamine issue using noncoding, nonrepetitive DNA from Old World monkeys (OWMs), chimpanzee, and human. minimal date 6 MYA human-chimpanzee divergence more than 2.5 million base pairs genomic sequences human we estimate maximal 0.99 regions these two species. This less half much smaller commonly used (3.5 10(-9)) eutherians. Further, 23 human-OWM divergence, 1.5 both introns fourfold degenerate sites humans OWMs. In addition, with New monkey (NWM) lineage as an outgroup, that 30% higher OWM lineage. Clearly, no Second, although studies indicated considerable variation mutation genome, recent study uniform rate. Using new existing intron sequence data primates, find significant positive correlation between GC content, refuting claim