Abstract # 88:

Scheduled for Thursday, August 18, 2005 07:00 PM-09:00 PM: (Cambridge/Oxford Room) Poster Presentation


A PHYLOGENY OF THE SOUTH AMERICAN HOWLER MONKEYS BASED ON MITOCHONDRIAL GENES, NUCLEAR GENES AND CHROMOSOMES

A. Sallenave
Dept. of Anthropology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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     Howler monkeys (Alouatta) are the most widely geographically distributed platyrrhine genus, comprising 8 to 10 species and a total of 23 taxa. Although previous studies have successfully established the reciprocal monophyly of the Mesoamerican and South American clades, the taxonomic classification and phylogenetic relationship among the South American species still remain controversial. Various conflicting hypotheses have been proposed based upon chromosomal and molecular data. However, no work has attempted a combined analysis of the multiple datasets. In this study, maximum-parsimony and Bayesian inference methods were used to estimate the phylogeny of South American howler monkeys by integrating all available evidence in a combined analysis of mitochondrial genes, nuclear genes and chromosomes. Analyses carried out both through parsimony and Bayesian methods consistently recovered two clades: one composed of A. guariba and A. belzebul and another composed of A. seniculus and A. sara. Parsimony analysis however, failed to provide strong support for any other phylogenetic relationships besides these clades. In contrast, Bayesian analyses recovered a well-resolved phylogeny for five of the six species included in this study, identifying four monophyletic clades strongly supported by 0.97-1.00 posterior probability values. The resulting hypothesis that best represented the combined evidence was (A. caraya ((A. guariba, A. belzebul) (A. macconnelli (A. seniculus, A. sara)))). It is here argued that combined analyses provide a useful approach for inferring phylogenetic relationships and understanding the evolutionary and biogeographic history of the South American howler monkeys.