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JONATHAN N. PAULI MATTHEW B. HAMILTON EDWARD B. CRAIN STEVEN W. BUSKIRK 《The Journal of wildlife management》2008,72(7):1650-1652
Abstract Although techniques to analyze and quantify DNA-based data have progressed, methods to noninvasively collect samples lag behind. Samples are generally collected from devices that permit coincident sampling of multiple individuals. Because of cross-contamination, substantive genotyping errors can arise. We developed a cost-effective (US$4.60/trap) single-capture hair trap for American martens (Martes americana). In the field, traps effectively targeted martens; >75% of all hair samples were identified as marten. Eighty percent of marten hair (n = 180) contained sufficient quality for DNA-based analyses. This effective and affordable trap can be used by managers to monitor mesocarnivore populations noninvasively. 相似文献
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Foraging ecology and patterns of diversification in dipteran parasitoids of fire ants in south Brazil 总被引:4,自引:0,他引:4
1. At least sixteen species of parasitoid flies in the genus Pseudacteon (family Phoridae) attack fire ants in the Solenopsis saevissima subcomplex in South America. Little is known of behavioural or ecological differences among Pseudacteon parasitoids of fire ants, although their coexistence in multispecies communities would suggest that important differences exist. Seven Pseudacteon species in two separate communities were studied in south-east Brazil. The way in which hosts detect and respond to the presence of parasitoids, attack rates of the parasitoids, and host location behaviour of the parasitoids were examined.
2. Reductions in fire ant recruitment were more closely related to the number of ants attacked along a foraging trail than to the amount of time that a phorid was present.
3. Pseudacteon solenopsidis differed from other phorid species by flying backwards while pursuing ants, by attacking at lower rates than other phorids, and by spending longer around fire ant foraging trails than other phorids before departing. Fire ant recruitment to food often rebounded in the continued presence of P. solenopsidis.
4. In each of the two communities, certain Pseudacteon species appeared frequently at Solenopsis foraging trails, whereas others appeared predominantly at mound disturbances. Two distinct size classes of phorids were present in each community, and the community with the larger ant host species also had a third and larger phorid species. No phorid species from the same community had similar body sizes and similar host location behaviours, although numerous species from different communities shared both of these traits.
5. Heterogeneity in host size and in the ecological circumstances under which hosts are vulnerable to attack appears to have influenced the evolution and perhaps maintenance of diverse Pseudacteon communities. 相似文献
2. Reductions in fire ant recruitment were more closely related to the number of ants attacked along a foraging trail than to the amount of time that a phorid was present.
3. Pseudacteon solenopsidis differed from other phorid species by flying backwards while pursuing ants, by attacking at lower rates than other phorids, and by spending longer around fire ant foraging trails than other phorids before departing. Fire ant recruitment to food often rebounded in the continued presence of P. solenopsidis.
4. In each of the two communities, certain Pseudacteon species appeared frequently at Solenopsis foraging trails, whereas others appeared predominantly at mound disturbances. Two distinct size classes of phorids were present in each community, and the community with the larger ant host species also had a third and larger phorid species. No phorid species from the same community had similar body sizes and similar host location behaviours, although numerous species from different communities shared both of these traits.
5. Heterogeneity in host size and in the ecological circumstances under which hosts are vulnerable to attack appears to have influenced the evolution and perhaps maintenance of diverse Pseudacteon communities. 相似文献
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MATTHEW J. PETERSEN MATTHEW A. BERTONE BRIAN M. WIEGMANN GREGORY W. COURTNEY 《Systematic Entomology》2010,35(3):526-545
Tipuloidea, the crane flies, are a diverse lineage of true flies (Insecta: Diptera) whose phylogenetic classification and taxonomy remain a challenge. Here we present the results of a quantitative phylogenetic analysis of Tipuloidea based on combined morphological characters (adult, larvae and pupae) and nuclear gene sequence data (28S rDNA and CAD). Forty‐five species, from 44 genera and subgenera, were sampled, representing the four putative families of Tipuloidea (Cylindrotomidae, Limoniidae, Pediciidae and Tipulidae sensu stricto). Analyses of individual datasets, although differing in overall topology, support the monophyly of several major lineages within Tipuloidea. Parsimony and Bayesian analyses using individual morphological and molecular datasets resulted in incongruent topologies. Increased resolution and tree support was obtained when both datasets (morphology and genes) were combined, in both combined evidence parsimony and Bayesian analyses, than when analysed separately. The recovered consensus phylogeny was not consistent with any previously proposed Tipuloidea classification, with previous importance assigned to character states shown here to represent losses and reversals seen as a major factor influencing erroneous classification. The results provided here, together with evidence from previous analyses, were used to append the Tipuloidea classification to supported evolutionary lineages. Tipuloidea is presented as two families: Pediciidae and Tipulidae. Pediciidae is recovered as the sister group to all remaining Tipuloidea. Our current phylogenetic hypothesis is not consistent with the existing subfamilial classification of the ‘Limoniidae’, which is paraphyletic with respect to a well‐supported Tipulinae + Cylindrotominae clade, whereas the three ‘limoniid’ subfamilies are para‐ or polyphyletic. The recognition of ‘Limoniidae’ as a valid monophyletic family is discouraged and the subfamilies of ‘Limoniidae’ are amended and placed within Tipulidae. A revised phylogenetic classification is proposed for the crane flies based on a synthesis of evidence from multiple genes and morphology. 相似文献
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aematin contents of engorged, male tsetse flies, Glossina pallidipes Austen, were compared with the packed cell volumes of oxen on which they had fed. Haematin contents icnreased with packed cell volume up to packed cell volumes of approximately 30%. Haematin contents appeared to level off or decline with further increase in packed cell volume. These results support a model of blood-feeding in tsetse flies in which the rate of blood consumption decreases as packed cell volume increases, because of increase in blood viscosity, and tsetse are unable to compensate for the decrease in consumption rate by feeding for a longer time. After allowing for the effects of packed cell volume, bloodmeal sizes of tsetse increased with ox body temperature. 相似文献