ИСТИНА

Introduction. The phylogeny of the order Eulipotyphla appears one of the most challenging tasks in Placentalia phylogeny, which illustrates all main problems of evolutionary reconstructions in mammals. Among four extant families of true insectivorans: Solenodontidae, Talpidae, Soricidae and Erinaceidae, the relationship between hedgehogs, moles and shrews remains an unresolved issue. In contrast to morphological hypotheses, molecular data give strong evidence for a sister-group relationship between shrews and hedgehogs to the exclusion of moles. The potential reason for the conflict between these hypotheses is the result of biased base composition of hedgehog and shrews nuDNA compared with moles and other mammals. Methods. To test the molecular phylogenetic hypothesis of Eulipotyphla we employed genomic data and obtained a multi-locus phylogeny based on 137 nuclear genes for a diverse taxon sample including Condilura and Diplomesodon. The phylogenetic trees of Erinaceidae, Talpidae and the main taxonomic groups of Soricidae were inferred from sequencing of 6-8 nuclear genes. Based on these nuclear data we estimated the timing of major cladogenetic events in Eulipotyphla. Results and Discussion. We recovered Solenodon as the sister of all other Lipotyphla, while Erinaceidae and Soricidae formed a clade to the exclusion of Talpidae. We also found that unlike Sorex, the rate of nucleotide changes in the line of Diplomesodon is not too high, and the nucleotide composition of it is not an anomalously GC-rich. Thus, Diplomesodon balances the entire branch of shrews on the multigene tree, which earlier was represented only by Sorex. Since the hedgehog+shrew situation is preserved, there is no reason to believe that the nucleotide composition and acceleration of Sorex relative to other insectivores are responsible for this signal. Erinaceidae. One of the main problem of phylogenetics of Erinaceidae is the large divergence time between Erinaceinae and Galericinae (about 50 My) and as a consequence, the lack of a close outgroup for each of the subfamilies. The other problem we found was an extremely high rate of nucleotide change in hedgehogs mtDNA compared with gymnures and high variation in base composition and evolutionary rate of nuclear genes in these groups. Our molecular phylogenetic analysis demonstrated long evolution of gymnures and their deep diversification with the earliest split estimated to occur in the Late Eocene. In contrast, crown spiny hedgehogs had undergone a sudden burst of radiation at the end of Miocene–early Pliocene. Talpidae. A potential source of conflict between molecular and morphological phylogenetic reconstructions of Talpidae – is a great role of parallelisms in the evolution of fossoriality. In contrast with the morphological concept, molecular data provide certain evidence for the independent evolution of extreme fossoriality in highly fossorial talpid tribes, Talpini and Scalopini. Soricidae. Phylogenetic reconstructions in Soricidae are complicated by contrasting rates of nucleotide change in subfamilies Soricinae and Crocidurinae that makes it difficult to determine the time of their split. Among Soricinae the key determinant of evolutionary success of Sorex in a temperate zone is that, in contrast to many other shrew genera, the red-toothed shrews benefited from the Pleistocene cooling. Among Crocidurinae, the genus Crocidura is also a successful group, but in the tropics. The recent findings suggest that the cryptic diversity of this genus and delimitation of species boundaries is a complex task especially for the groups of recently radiated Asian species.