Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher.
Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?
Some links on this page may take you to non-federal websites. Their policies may differ from this site.
-
The Pallas’s cat (Otocolobus manul) is one of the most understudied taxa in the Felidae family. The species is currently assessed as being of “Least Concern” in the IUCN Red List, but this assessment is based on incomplete data. Additional ecological and genetic information is necessary for the long-term in situ and ex situ conservation of this species. We identified 29 microsatellite loci with sufficient diversity to enable studies into the individual identification, population structure, and phylogeography of Pallas’s cats. These microsatellites were genotyped on six wild Pallas’s cats from the Tibet Autonomous Region and Mongolia and ten cats from a United States zoo-managed population that originated in Russia and Mongolia. Additionally, we examined diversity in a 91 bp segment of the mitochondrial 12S ribosomal RNA (MT-RNR1) locus and a hypoxia-related gene, endothelial PAS domain protein 1 (EPAS1). Based on the microsatellite and MT-RNR1 loci, we established that the Pallas’s cat displays moderate genetic diversity. Intriguingly, we found that the Pallas’s cats had one unique nonsynonymous substitution in EPAS1 not present in snow leopards (Panthera uncia) or domestic cats (Felis catus). The analysis of the zoo-managed population indicated reduced genetic diversity compared to wild individuals. The genetic information from this study is a valuable resource for future research into and the conservation of the Pallas’s cat.more » « less
-
Hippopotamid phylogeny has proven difficult to resolve with proposed relationships between extant and fossil species receiving mixed levels of support. Of particular interest is the divergence between the two extant hippopotamid species, the well-known common hippopotamus (Hippopotamus amphibius) and the enigmatic pygmy hippopotamus (Choeropsis liberiensis). Previous studies have relied on morphological and fossil evidence to identify the ancestral species at the core of this divergence and its timing. In this study, we assembled a molecular matrix of 26 nuclear gene sequences from 11 ungulate species with two primates as an outgroup. We used a Bayesian relaxed molecular clock approach to reconstruct a calibrated time tree for Cetartiodactyla and estimate the divergence date between the common and pygmy hippopotamus. While previous morphological studies have estimated this event to have occurred sometime during the Late Miocene (between 11.6 and 5.3 million years ago), our nuclear gene-based estimates suggest a more recent split of about 4.04 Ma (95% confidence interval: 8.31–1.97 Ma) via RelTime-ML or 2.4 Ma (95% confidence interval: 3.1–1.6 Ma) via MCMCTree. These more recent estimates correspond with the Early Pliocene – Early Pleistocene sub-epochs and align most closely with the results of previous genomic studies. We discuss how our results compare with previous estimates based on both morphological and molecular studies, some of which extend the predicted range of this divergence date even further back in time. Our results suggest a different path of evolution for the understudied pygmy hippopotamus and reveal that morphological evidence alone may not resolve the correct hippopotamid phylogenetic and time trees. We suggest that the common and pygmy hippopotamus may be phylogenetically closer than once believed. Our results also call for further studies to develop a combined approach incorporating both molecular and morphological evidence to reach a consensus on the evolutionary patterns and timing that led to modern hippopotamid evolution.more » « less
An official website of the United States government
