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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]

The initial contact of European populations with indigenous populations of the Americas produced diverse admixture processes across North, Central, and South America. Recent studies have examined the genetic structure of indigenous populations of Latin America and the Caribbean and their admixed descendants, reporting on the genomic impact of the history of admixture with colonizing populations of European and African ancestry. However, relatively little genomic research has been conducted on admixture in indigenous North American populations. In this study, we analyze genomic data at 475,109 single-nucleotide polymorphisms sampled in indigenous peoples of the Pacific Northwest in British Columbia and Southeast Alaska, populations with a well-documented history of contact with European and Asian traders, fishermen, and contract laborers. We find that the indigenous populations of the Pacific Northwest have higher gene diversity than Latin American indigenous populations. Among the Pacific Northwest populations, interior groups provide more evidence for East Asian admixture, whereas coastal groups have higher levels of European admixture. In contrast with many Latin American indigenous populations, the variance of admixture is high in each of the Pacific Northwest indigenous populations, as expected for recent and ongoing admixture processes. The results reveal some similarities but notable differences between admixture patterns in the Pacific Northwest and those in Latin America, contributing to a more detailed understanding of the genomic consequences of European colonization events throughout the Americas. [ABSTRACT FROM AUTHOR]