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81.
82.
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
83.
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
84.
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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86.
DANIEL K. RISKIN PAUL A. RACEY 《Biological journal of the Linnean Society. Linnean Society of London》2010,99(2):233-240
Individuals of most bat species hang head‐down by their toenails from rough surfaces, but Madagascar's endemic sucker‐footed bat (Myzopoda aurita) clings head‐up to smooth leaves using specialized pads on its wrists and ankles. We investigated the adhesive performance of 28 individuals and found that attachment performance on brass was not affected by the presence or absence of a seal around the pad–surface interface. Furthermore, on smooth acrylic, the wrist pads were more than nine‐fold weaker when lifted perpendicular to the surface than when pulled parallel to it. The unimportance of a seal and the difference in strength in those directions on a smooth surface are characteristic of wet adhesion, but not of suction. Thus, despite its name, the sucker‐footed bat appears to adhere using wet adhesion. We observed that when wrist pads were pushed anteriorly, they unpeeled easily from the surface because of deformation of the pads. This most likely permits rapid detachment during crawling, but would also cause passive detachment if bats roosted head‐down. This provides an ecomorphological explanation to the head‐up roosting behaviour of these unique bats. The results obtained in the present study thus link morphology, behaviour, and roosting ecology for an enigmatic Malagasy endemic. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 233–240. 相似文献
87.
Calli derived from seedlings of the parasitic plant Orobancheaegyptiaca were grown on enriched nutrient agar. Growth wasenhanced by the addition of 0.1 mg 11 NAA and 5 % coconutmilk. The calli developed two kinds of elongated protrusions:thin ones which resemble the young root radicle and thick oneswhich resemble the adventitious roots of Orobanche plants. Bothformed pad-like structures when touching the substrate. In liquidculture, some of the calli were observed to surround isolatedcultured tomato roots. Orobanche aegyptiaca Pers., in vitro culture, germination, coconut milk, root parasite 相似文献
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The Role of Exchange in Productive Specialization 总被引:1,自引:0,他引:1
Nomadic pastoralists are specialists in complex systems of land use. Their own productive strategies are dependent in large part upon the conversion rates of their products to imported items from other sectors of a larger economy. Changes in these conversion rates are likely to arise for a number of reasons; pastoralists respond to such changes in various ways, depending upon their past histories and current conditions. The case of the Yörük, specialized pastoralists of southeastern Turkey, is used to illustrate this process of changing productive strategies. Generalizations are sought concerning the ways in which large systems of land use become more or less specialized through time, in terms of the consequences of shifting exchange conditions for the productive strategies of component households. [economic anthropology, pastoralism, complex society, interpopulation exchange] 相似文献