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DANIEL G. MULCAHY 《Biological journal of the Linnean Society. Linnean Society of London》2007,92(3):483-500
The Leptodeirini has been presumed to be a monophyletic assemblage based on albumin immunological data and morphology and consisted of neotropical cat-eyed snakes ( Leptodeira ), blunt-headed vine snakes ( Imantodes ), nightsnakes ( Eridiphas , Hypsiglena , and Pseudoleptodeira ), and the cloud forest snake ( Cryophis ). In the present study, approximately 1.4 kb of mitochondrial DNA sequence data (from cob and nad4 ) were collected to test the monophyly of the Leptodeirini. These data were analysed using maximum parsimony, maximum likelihood, and Bayesian methods. None of the results supported the monophyly of the Leptodeirini. There was strong support for a clade containing Imantodes and Leptodeira , and another clade containing the nightsnakes, with the latter placed closer to Cryophis and other dipsadine genera ( Sibon , Dipsas , and Atractus ). This partial reassessment of the Dipsadinae infers the group to have an ancestral condition of being rear-fanged, mildly venomous, and feeding on ectothermal vertebrates, with a more derived radiation that has lost the rear-fanged, venomous condition and has a diet specialized on invertebrates. A brief discussion on the biogeography of the dipsadines shows the group to be much older (Palaeocene), consistent with earlier views, as opposed to a more recent (Miocene) hypothesis, as has been recently suggested. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 92 , 483–500. 相似文献
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Accelerating Possession: Global Future of Property and Personhood . Bill Maurer and Gabrielle Schwab, eds. New York: Columbia University Press, 2006. 275 pp. 相似文献
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Glucocorticoids and maintenance of blood pressure and plasma volume of adrenalectomized dogs subjected to stress 总被引:2,自引:0,他引:2
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RYAN M. HUEBINGER THOMAS W. J. DE MAAR LAURENCE H. WOODRUFF DANIEL POMP EDWARD E. LOUIS 《Molecular ecology resources》2006,6(4):1150-1151
Eight microsatellite loci were isolated from a genomic DNA library created from Grant's gazelle (Gazella granti). Observed and expected levels of heterozygosity were computed utilizing 20 individuals from a population in Central Kenya. Tests for Hardy–Weinberg equilibria were conducted and found that two of the eight loci deviated from equilibrium in this population. These markers were developed to analyse the genetic effects of culling and isolation on a game preserve in Kenya. 相似文献
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CLIVE A. MCALPINE MICHIALA E. BOWEN JOHN G. CALLAGHAN DANIEL LUNNEY JONATHAN R. RHODES DAVID L. MITCHELL DAVID V. PULLAR HUGH P. POSZINGHAM 《Austral ecology》2006,31(4):529-544
Abstract Predicting the various responses of different species to changes in landscape structure is a formidable challenge to landscape ecology. Based on expert knowledge and landscape ecological theory, we develop five competing a priori models for predicting the presence/absence of the Koala (Phascolarctos cinereus) in Noosa Shire, south‐east Queensland (Australia). A priori predictions were nested within three levels of ecological organization: in situ (site level) habitat (<1 ha), patch level (100 ha) and landscape level (100–1000 ha). To test the models, Koala surveys and habitat surveys (n = 245) were conducted across the habitat mosaic. After taking into account tree species preferences, the patch and landscape context, and the neighbourhood effect of adjacent present sites, we applied logistic regression and hierarchical partitioning analyses to rank the alternative models and the explanatory variables. The strongest support was for a multilevel model, with Koala presence best predicted by the proportion of the landscape occupied by high quality habitat, the neighbourhood effect, the mean nearest neighbour distance between forest patches, the density of forest patches and the density of sealed roads. When tested against independent data (n = 105) using a receiver operator characteristic curve, the multilevel model performed moderately well. The study is consistent with recent assertions that habitat loss is the major driver of population decline, however, landscape configuration and roads have an important effect that needs to be incorporated into Koala conservation strategies. 相似文献