Genetic Diversity and Distinctiveness of the Proboscis Monkeys of the Klias Peninsula, Sabah, Malaysia

Proboscis monkey populations have declined in recent decades due to agricultural practices. In Sabah, the easternmost state of Malaysia located in northern Borneo, four clusters of proboscis monkey populations can be found among eastern waterways while one western cluster persists on the Klias Peninsula. The goal of this study was to assess genetic diversity within the Klias Peninsula, and to compare the Klias populations to those of the eastern waterways for which previously generated data exists. Researchers collected fecal samples and obtained 21 mtDNA control region sequences representing a central and a southern Klias group. Nine haplotypes and three haplogroups were identified, indicating that the Klias proboscis monkeys have maintained a decent level of diversity. The researchers pointed out that such diversity is consistent with primates with high female transfer between groups, but limited mitochondrial structure within Klias suggests such transfer has occurred only recently. Additionally, haplotype diversity and nucleotide diversity were greater in the southern Klias group compared to the central, and little evidence was found for regional genetic structure across Sabah. The authors argue that conservation efforts should aim to restore and maintain connectivity between the central and southern Klias groups.