Catarrhine phylogeny: Noncoding DNA evidence for a diphyletic origin of the mangabeys and for a human-chimpanzee clade

Maximum-parsimony send maximum-likelihood analyses of two of the serum albumin gene's intron sequences from 24 catarrhines (17 cercopithecid and 7 hominid) and 3 platyrrhines tan outgroup to the catarrhines) yielded results on catarrhine phylogeny that are congruent with those obtained with noncoding sequences of the gamma (1)-gamma (2) globin gene genomic region, using only those flanking and intergenic gamma sequences that in their history were not involved in gene conversion. A data set that combined in a tandem alignment these two sets of noncoding DNA orthologues ham the two unlinked nuclear genomic loci yielded the following confirmatory results both on the course of cladistic branchings (the divisions in a cladistic classification of higher ranking taxa into subordinate taxa) and on the ages of the taxa teach taxon representing a clade). The cercopithecid branch of catarrhines, at similar to 14 Ma (mega annum) divided into Colobini (the leaf-eating Old World monkeys) and Cercopithecini (the cheek-pouched Old World monkeys). At similar to 10-9 Ma, Colobini divided into an African clade, Colobina, and an Asian clade, Presbytina; similarly at this time level, Cercopithecini divided into Cercopithecina (the guenons, patas, and green monkeys) and Papionina. At similar to7 Ma, Papionina divided into Macaca, Cercocebus, and Papio. At similar to5 Ma, Cercocebus divided subgenerically into C: (Cercocebus) for terrestrial mangabeys and C. (Mandrillus) for drills and mandrills, while at similar to4 Ma Papio divided subgenerically into P. (Locophocebus) for arboreal mangabeys, P. (Theropithecus) for gelada baboons, and P. (Papio) for hamadryas baboons. In turn, the hominid branch of catarrhines at similar to 18 Ma divided into Hylobatini (gibbons and siamangs) and Hominini; at similar to 14 Ma, Hominini divided into Pongina (orangutans) and Hominina; at similar to7 Ma, Hominina divided into Gorilla and Homo; and at similar to6-5 Ma, Homo divided subgenerically into H. (Homo) for humans and H, (Pan) for common and bonobo chimpanzees. Rates of noncoding DNA evolution were assessed using a data set of noncoding gamma sequence orthologues that represented 18 catarrhines, 16 platyrrhines, 3 non-anthropoid primates (2 tarsiers and 1 strepsirhine), and rabbit las outgroup to the primates). Results obtained with this data set revealed a faster rate of nuclieotide substitutions in the early primate lineage to the anthropoid (platyrrhine/catarrhine) ancestor than from that ancestor to the present. Rates were slower in catarrhines than in platyrrhines, slower in the cheek-pouched than in the leaf-eating cercopithecids, and slower yet in the hominids, On relating these results to data on brain sizes and life spans, it was suggested that life-history strategies that favor intelligence and longer life spans also select for decreases in de novo mutation rates. (C) 2000 Academic Press.