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61.
MARY BETH REW M. ZACHARIAH PEERY STEVEN R. BEISSINGER MARTINE BRUB JEFFREY D. LOZIER EMILY M. RUBIDGE PER J. PALSB
LL 《Molecular ecology resources》2006,6(1):241-244
We developed 31 novel, polymorphic microsatellite loci in the marbled murrelet (Brachyramphus marmoratus), a critically endangered seabird. Variability was tested on 15 individuals from the Santa Cruz, California population, with each locus characterized by two to 12 alleles. Observed levels of heterozygosity ranged from 0.13 to 0.93. These loci provide a valuable means of assessing the population structure and demographic parameters of this species, which may be critical to its conservation across a fragmented habitat. 相似文献
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Adaptation is conventionally regarded as occurring at the level of the individual organism. However, in recent years there has been a revival of interest in the possibility for group adaptations and superorganisms. Here, we provide the first formal theory of group adaptation. In particular: (1) we clarify the distinction between group selection and group adaptation, framing the former in terms of gene frequency change and the latter in terms of optimization; (2) we capture the superorganism in the form of a ‘group as maximizing agent’ analogy that links an optimization program to a model of a group‐structured population; (3) we demonstrate that between‐group selection can lead to group adaptation, but only in rather special circumstances; (4) we provide formal support for the view that between‐group selection is the best definition for ‘group selection’; and (5) we reveal that mechanisms of conflict resolution such as policing cannot be regarded as group adaptations. 相似文献
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We developed eight microsatellite markers for Cryptocarya mackinnoniana to study the spatial genetic structure and ecological correlates of parentage in secondary rainforests in Australia's Wet Tropics. The microsatellite loci were screened in 99 trees, and 623 seedlings < 0.24 m tall, at a site extending from primary rainforest into adjacent 50‐year‐old secondary rainforest. The eight loci were polymorphic, exhibiting between three and 11 alleles, and gene diversity (HE) from 0.25 to 0.84. For the trees, no departures from Hardy–Weinberg equilibrium were detected, except at locus Cm03, which had an estimated null allele frequency of 0.0903. No locus combinations exhibited linkage disequilibrium. 相似文献
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