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Abstract: The mammalian order Carnivora has attracted the attention of scientists of various disciplines for decades, leading to intense interest in defining its supra-familial relationships. In the last few years, major changes to the topological structure of the carnivoran tree have been proposed and supported by various molecular data sets, radically changing the traditional view of family composition in this order. Although a sequence of molecular studies have established a growing consensus with respect to most inter-familial relationships, no analysis so far has included all carnivoran lineages (both feliform and caniform) in an integrated data set, so as to determine comparative patterns of diversification. Moreover, no study conducted thus far has estimated divergence dates among all carnivoran families, which is an important requirement in the attempt to understand the patterns and tempo of diversification in this group. In this study, we have investigated the phylogenetic relationships among carnivoran families, and performed molecular dating analyses of the inferred nodes. We assembled a molecular supermatrix containing 14 genes (7765bp), most of which have not been previously used in supra-familial carnivoran phylogenetics, for 50 different genera representing all carnivoran families. Analysis of this data set led to consistent and robust resolution of all supra-familial nodes in the carnivoran tree, and allowed the construction of a molecular timescale for the evolution of this mammalian order. [Copyright &y& Elsevier]

Abstract: Genetic variation in cat breeds was assessed utilizing a panel of short tandem repeat (STR) loci genotyped in 38 cat breeds and 284 single-nucleotide polymorphisms (SNPs) genotyped in 24 breeds. Population structure in cat breeds generally reflects their recent ancestry and absence of strong breed barriers between some breeds. There is a wide range in the robustness of population definition, from breeds demonstrating high definition to breeds with as little as a third of their genetic variation partitioning into a single population. Utilizing the STRUCTURE algorithm, there was no clear demarcation of the number of population subdivisions; 16 breeds could not be resolved into independent populations, the consequence of outcrossing in established breeds to recently developed breeds with common ancestry. These 16 breeds were divided into 6 populations. Ninety-six percent of cats in a sample set of 1040 were correctly assigned to their classified breed or breed group/population. Average breed STR heterozygosities ranged from moderate (0.53; Havana, Korat) to high (0.85; Norwegian Forest Cat, Manx). Most of the variation in cat breeds was observed within a breed population (83.7%), versus 16.3% of the variation observed between populations. The hierarchical relationships of cat breeds is poorly defined as demonstrated by phylogenetic trees generated from both STR and SNP data, though phylogeographic grouping of breeds derived completely or in part from Southeast Asian ancestors was apparent. [Copyright &y& Elsevier]

Selective breeding of the guanaco and vicuña indisputably led to the domestic llama and alpaca. However, the place, time and process of domestication remain poorly documented, exacerbated by increased evidence of historic and recent introgression among both domestic populations, especially those involving alpaca. Here, we report the first comprehensive assessment of patterns of microsatellite variation of 13 polymorphic microsatellites in 797 individuals representing 4 species and 2 subspecies to estimate historic and ongoing patterns of gene flow. Our results confirm that llamas were domesticated almost exclusively from the northern subspecies of guanaco (Lama guanicoe cacsilensis), but cluster analyses did not support previous findings that alpacas are solely derived from the northern subspecies of vicuña (Vicugna mensalis), with some more-recent admixture with southern populations. We also confirmed continued gene flow between llama and alpaca, and found evidence for crosses between presumably feral llamas and guanacos in northern Chile. Our results highlight the need to develop and test more-accurate markers and tools for assessing the genetic heritage of individuals, to link phenotypic variation with genetic ancestry, and to conserve historic patterns of unique variation among both the wild and domestic populations. • The dominant herbivores of the arid and semi-arid habitats of South America include wild and domestic species. • The genetic and phenotypic integrity of the domestic llama and alpaca are increasingly being threatened by interbreeding. • Loss of vicuña genetic signal in alpaca is due to hybridization and introgression among South American camelids. [ABSTRACT FROM AUTHOR]