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The evolutionary theory of aging predicts that species will experience delayed senescence and increased longevity when rates of extrinsic mortality are reduced, It has long been recognized that birds and bats are characterized by lower rates of extrinsic mortality and greater longevities than nonvolant endotherms, presumably because flight reduces exposure to terrestrial predators, disease, and environmental hazards. Like flight, arboreality may act to reduce extrinsic mortality, delay senescence, and increase longevity and has been suggested as an explanation for the long lifespans of primates. However, this hypothesis has yet to be tested in mammals in general. We analyze a large dataset of mammalian longevity records to test whether arboreal mammals are characterized by greater longevities than terrestrial mammals. Here, we show that arboreal mammals are longer lived than terrestrial mammals at common body sizes, independent of phylogeny. Subclade analyses demonstrate that this trend holds true in nearly every mammalian subgroup, with two notable exceptions-metatherians (marsupials) and euarchontans (primates and their close relatives). These subgroups are unique in that each has experienced a long and persistent arboreal evolutionary history, with subsequent transitions to terrestriality occurring multiple times within each group. In all other clades examined, terrestriality appears to be the primitive condition, anspedes that become arboreal tend to experience increased longevity, often independently in multiple lineages within each dade. Adoption of an arboreal lifestyle may have allowed for increased longevity in these lineages and in primates in general. Overall, these results confirm the fundamental predictions of the evolutionary theory of aging. [ABSTRACT FROM AUTHOR]

Long-tailed macaques (Macaca fascicularis) have a wide geographic distribution across mainland and insular Southeast Asia. The evolutionary history of long-tailed macaques has been examined extensively through comparison of phenotypic variation and by phylogenetic analyses of molecular genetic data. Nonetheless, the complex evolutionary history of M. fascicularis throughout Southeast Asia is not fully understood. For the present study, we performed a Bayesian phylogenetic analysis of M. fascicularis mitochondrial 12S/tRNA-val/16S sequences to examine the evolutionary relationships of the long-tailed macaques from Singapore. More generally, we hoped to gain a better understanding of the evolutionary history of long-tailed macaques throughout Southeast Asia. We used previously archived sequences in GenBank and new sequences from Singapore (n=34) and Bali, Indonesia (n=2) in a Bayesian phylogenetic framework to co-infer evolutionary histories and divergence dates. Our results revealed two large clades, one composed of haplotypes primarily from Sundaic islands populations, and the second primarily from continental populations. These two larger clades comprise four primary regional clades. All three haplotypes from Singapore form a well-supported subclade within a larger peninsular clade. A medianjoining network of haplotypes mirrored the results from the phylogenetic analyses. We found divergence dates that were largely consistent with previous studies using complete mitochondrial genomes. Based on an assessment of phylogenetic relationships, the pattern of estimated divergence dates, and the available fossil record, we suggest that the evolutionary history of M. fascicularis likely included multiple dispersal events. [ABSTRACT FROM AUTHOR]