title: Inferring the evolutionary histories of divergences in Hylobates and Nomascus gibbons through multilocus sequence data.
abstract: BACKGROUND
  Gibbons (Hylobatidae) are the most diverse group of living apes. They exist as geographically-contiguous species which diverged more rapidly than did their close relatives, the great apes (Hominidae). Of the four extant gibbon genera, the evolutionary histories of two polyspecific genera, Hylobates and Nomascus, have been the particular focus of research but the DNA sequence data used was largely derived from the maternally inherited mitochondrial DNA (mtDNA) locus.
  
  
  RESULTS
  To investigate the evolutionary relationships and divergence processes of gibbon species, particularly those of the Hylobates genus, we produced and analyzed a total of 11.5 kb DNA of sequence at 14 biparentally inherited autosomal loci. We find that on average gibbon genera have a high average sequence diversity but a lower degree of genetic differentiation as compared to great ape genera. Our multilocus species tree features H. pileatus in a basal position and a grouping of the four Sundaic island species (H. agilis, H. klossii, H. moloch and H. muelleri). We conducted pairwise comparisons based on an isolation-with-migration (IM) model and detect signals of asymmetric gene flow between H. lar and H. moloch, between H. agilis and H. muelleri, and between N. leucogenys and N. siki.
  
  
  CONCLUSIONS
  Our multilocus analyses provide inferences of gibbon evolutionary histories complementary to those based on single gene data. The results of IM analyses suggest that the divergence processes of gibbons may be accompanied by gene flow. Future studies using analyses of multi-population model with samples of known provenance for Hylobates and Nomascus species would expand the understanding of histories of gene flow during divergences for these two gibbon genera.
authors.affiliation: Department of Primatology, Max-Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, Leipzig 04103, Germany. yichiao_chan@eva.mpg.de
authors.forename: Yi-Chiao
authors.initials: YC
authors.lastname: Chan
authors.forename: Christian
authors.initials: C
authors.lastname: Roos
authors.forename: Miho
authors.initials: M
authors.lastname: Inoue-Murayama
authors.forename: Eiji
authors.initials: E
authors.lastname: Inoue
authors.forename: Chih-Chin
authors.initials: CC
authors.lastname: Shih
authors.forename: Kurtis Jai-Chyi
authors.initials: KJ
authors.lastname: Pei
authors.forename: Linda
authors.initials: L
authors.lastname: Vigilant
mesh_terms: D025041:Animal Migration; D000818:Animals; D005075:Biological Evolution; D004272:DNA, Mitochondrial / Q000235:genetics; D051456:Gene Flow; D006922:Hylobates / Q000145:classification* / Q000235:genetics*; D016674:Hylobatidae / Q000145:classification / Q000235:genetics; D058885:Multilocus Sequence Typing; D010802:Phylogeny
chemical_list: D004272:DNA, Mitochondrial