The genetic bases of demographic changes and artificial selection underlying domestication are of great interest in evolutionary biology. Here we perform whole-genome sequencing of multiple grey wolves, Chinese indigenous dogs and dogs of diverse breeds. Demographic analysis show that the split between wolves and Chinese indigenous dogs occurred 32,000 years ago and that the subsequent bottlenecks were mild. Therefore, dogs may have been under human selection over a much longer time than previously concluded, based on molecular data, perhaps by initially scavenging with humans. Population genetic analysis identifies a list of genes under positive selection during domestication, which overlaps extensively with the corresponding list of positively selected genes in humans. Parallel evolution is most apparent in genes for digestion and metabolism, neurological process and cancer. Our study, for the first time, draws together humans and dogs in their recent genomic evolution.

Although a mitochondrial DNA barcode has been shown to be of great utility for species identification and discovery in an increasing number of diverse taxa, caution has been urged with its application to one of the most taxonomically diverse vertebrate groups - the amphibians. Here, we test three of the perceived shortcomings of a CO1 DNA barcode's utility with a group of Holarctic amphibians: primer fit, sequence variability and overlapping intra- and interspecific variability. We found that although the CO1 DNA barcode priming regions were variable, we were able to reliably amplify a CO1 fragment from degenerate primers and primers with G-C residues at the 3' end. Any overlap between intra- and interspecific variation in our taxonomic sampling was due to introgressive hybridization (Bufo/Anaxyrus), complex genetics (Ambystoma) or incomplete taxonomy (Triturus). Rates of hybridization and species discovery are not expected to be greater for amphibians than for other vertebrate groups, and thus problems with the utility of using a single mitochondrial gene for species identification will not be specific to amphibians. Therefore, we conclude that there is greater potential for a CO1 barcode's use with amphibians than has been reported to date. A large-scale effort to barcode the amphibians of the world, using the same primary barcode region of CO1, will yield important findings for science and conservation.

species tree analyses resolve the radiation of the widespread Bufo bufo species group (Anura, Bufonidae), Molecular Phylogenetics and Evolution (2011),

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We studied skull, vertebral column, and limb skeleton development in Japanese clawed sala mander Onychodactylus japonicus (Hynobiidae). The study is based on the ontogenetic series of embryos and larvae obtained from wild captured adults by artificial induction of breeding using hormonal stimulation. The first stages of the skeleton formation in O. japonicus are shifted to the late embryonic period and hatching lar vae already possess a well ossified vertebral column, large number of skull ossifications and show signs of ossi fication in the forelimb skeleton. Compared to the primitive pattern of the skeleton development typical for other hynobiid salamanders, O. japonicus shows a number of heterochronies related to embryonization. In particular, this species is characterized by an earlier ossification of the vertebral column compared to that of the skull and by the delayed development and early reduction of the coronoid. Our results, along with the pre viously reported data on the skeleton development in the Fischer's clawed salamander O. fischeri (Smirnov and Vassilieva, 2002), indicate that the genus Onychodactylus is characterized by the loss or reduction of sev eral skeletal features typically found at early larval stages in other Hynobiidae species. In particular, provi sional bones (especially the coronoid) and their dentition are underdeveloped. In addition, it is corroborated that the first tooth generation is absent in Onychodactylus, whereas such monocuspid nonpedicellate tooth generation normally develops at the early larval stages of other caudate amphibians. Since similar patterns of skeleton ontogeny are observed in other caudate groups with different extent of embryonization, it is pro posed that, in different lineages of Urodela, the evolution of ontogeny followed similar pathways and was accompanied by the same changes in skeletogenesis.