The Experts below are selected from a list of 243 Experts worldwide ranked by ideXlab platform
Matthew R E Symonds - One of the best experts on this subject based on the ideXlab platform.
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phylogeny and life histories of the Insectivora controversies and consequences
Biological Reviews, 2005Co-Authors: Matthew R E SymondsAbstract:The evolutionary relationships of the eutherian order Insectivora (Lipotyphla sensu stricto) are the subject of considerable debate. The difficulties in establishing insectivore phylogeny stem from their lack of many shared derived characteristics. The grouping is therefore something of a ‘wastebasket ’ taxon. Most of the older estimates of phylogeny, based on morphological evidence, assumed insectivore monophyly. More recently, molecular phylogenies argue strongly against monophyly, although they differ in the extent of polyphyly inferred for the order. I review the history of insectivore phylogenetics and systematics, focussing on the relationships between the six extant families (Erinaceidae – hedgehogs and moonrats, Talpidae – moles and desmans, Soricidae – shrews, Solenodontidae – solenodons, Tenrecidae – tenrecs and otter-shrews and Chrysochloridae – golden moles). I then examine how these various phylogenetic hypotheses influence the results of comparative analyses and our interpretation of insectivore life-history evolution. I assess which particular controversies have the greatest effect on results, and discuss the implications for comparative analyses where the phylogeny is controversial. I also explore and suggest explanations for certain insectivore life-history trends : increased gestation length and litter size in tenrecs, increased encephalization in moles, and the mixed fast and slow life-history strategies in solenodons. Finally, I consider the implications for comparative analyses of the recent strongly supported phylogenetic hypothesis of an endemic African clade of mammals that includes the insectivore families of tenrecs and golden moles.
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life histories of the Insectivora the role of phylogeny metabolism and sex differences
Journal of Zoology, 1999Co-Authors: Matthew R E SymondsAbstract:Life-history data for 63 species from the mammalian order Insectivora have been collated from the literature. These data were analysed for covariation and for correlations with body mass, brain mass and mass-specific resting metabolic rate. An independent contrasts method has been used to remove the effect of phylogeny. Due to uncertainties surrounding their evolutionary relationships, 22 different phylogenies of insectivores have been used as a basis for comparative analysis. The results show that several key correlations between life-history variables are only significant when certain phylogenies are used, highlighting the problems of such analyses when the phylogeny used is inaccurate. After removing the effect of phylogeny, relatively few significant correlations remain. Insectivores that have a high body mass have relatively lower metabolic rates, longer lifespans and longer gestation lengths. There is some support for a fast–slow continuum in insectivore life-history evolution: there are some significant positive correlations between measures of growth rates (e.g. gestation length and age at weaning) and lifespan, and some negative correlations between growth rates and measures of reproductive output. It is suggested that the seasonality of life of many insectivores may have played an influential role in the evolution of the group, in particular in delaying the onset of sexual maturity. There is little indication that brain size influences life-history evolution in this order, but metabolism may play an important role. The energetic requirements of maintaining high metabolic rates in small mammals such as insectivores may be constraining life histories to a greater extent than occurs in larger mammals. This effect may have obscured the relationship between metabolic rate and life histories in wider inter-order analyses. Finally, there is considerable evidence that sex differences play a large role in shaping insectivore evolution, and it is suggested that this factor must be considered more often in future studies of mammalian life histories in general.
Ji Li - One of the best experts on this subject based on the ideXlab platform.
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distribution of several Insectivora and the drying trend since the pleistocene in north china
Quaternary International, 2013Co-Authors: Yongxiang Li, Yunxiang Zhang, Ji LiAbstract:Abstract This paper describes the changes of distribution in geography and geohistory of five genera of fossil Insectivora of the Shanyangzhai fauna in China, and compares these with their modern geographical and ecological distribution. The comparison showed that since the Pleistocene, the diffusion of the common hedgehog Erinaceus, the migration of the shrew Sorex, the water shrew Neomys, and the genera Crocidura and Scaptochirus, all indicate displacement of warm-dry environments in north China.
Yongxiang Li - One of the best experts on this subject based on the ideXlab platform.
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distribution of several Insectivora and the drying trend since the pleistocene in north china
Quaternary International, 2013Co-Authors: Yongxiang Li, Yunxiang Zhang, Ji LiAbstract:Abstract This paper describes the changes of distribution in geography and geohistory of five genera of fossil Insectivora of the Shanyangzhai fauna in China, and compares these with their modern geographical and ecological distribution. The comparison showed that since the Pleistocene, the diffusion of the common hedgehog Erinaceus, the migration of the shrew Sorex, the water shrew Neomys, and the genera Crocidura and Scaptochirus, all indicate displacement of warm-dry environments in north China.
J Hausser - One of the best experts on this subject based on the ideXlab platform.
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microsatellite conservation polymorphism and gc content in shrews of the genus sorex Insectivora mammalia
Molecular Biology and Evolution, 1998Co-Authors: Francois Balloux, Eric Ecoffey, Luca Fumagalli, Jerome Goudet, Andreas Wyttenbach, J HausserAbstract:Microsatellite conservation, polymorphism, and GC content in shrews of the genus Sorex (Insectivora, Mammalia)
Yunxiang Zhang - One of the best experts on this subject based on the ideXlab platform.
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distribution of several Insectivora and the drying trend since the pleistocene in north china
Quaternary International, 2013Co-Authors: Yongxiang Li, Yunxiang Zhang, Ji LiAbstract:Abstract This paper describes the changes of distribution in geography and geohistory of five genera of fossil Insectivora of the Shanyangzhai fauna in China, and compares these with their modern geographical and ecological distribution. The comparison showed that since the Pleistocene, the diffusion of the common hedgehog Erinaceus, the migration of the shrew Sorex, the water shrew Neomys, and the genera Crocidura and Scaptochirus, all indicate displacement of warm-dry environments in north China.
