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We used ancient DNA techniques to amplify mitochondrial DNA fragments [cytochrome b (cyt b ) and control region (CR)] from four museum specimens that represent, to our knowledge, the last testimony of the introduction of – now extinct – mongooses in Italy. We assessed the identity, origin and genetic variability of Italian mongooses using a species-level assignation Bayesian approach and haplotype network analysis. The genetic diversity (cyt b and CR) among Italian individuals was null. The cyt b sequences from the four museum specimens clearly established the Indian grey mongoose Herpestes edwardsii as the species having been introduced in Italy in the mid-XXth century. The latter had at least been released twice within a period of 10 years (Circeo NP and Capalbio, c . 200 km northward), probably from the same captive stock of the Giardino Zoologico di Roma. Assessment of genetic variability and haplotype network including native representatives of H. edwardsii suggested that the introduced pool likely originated from Pakistan or India. It appears that a combination of deleterious factors including low genetic diversity, restricted range and nonadaptation to western Palaearctic winter conditions is responsible for the extinction of the species in Italy. However, the lack of knowledge on the life-history traits and population dynamics of H. edwardsii prevents from further discussion of the factors that likely promoted its extinction process. 相似文献
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Thulin CG Simberloff D Barun A McCracken G Pascal M Islam MA 《Molecular ecology》2006,15(13):3947-3956
The combination of founder events, random drift and new selective forces experienced by introduced species typically lowers genetic variation and induces differentiation from the ancestral population. Here, we investigate microsatellite differentiation between introduced and native populations of the small Indian mongoose (Herpestes auropunctatus). Many expectations based on introduction history, such as loss of alleles and relationships among populations, are confirmed. Nevertheless, when applying population assignment methods to our data, we observe a few specimens that are incorrectly assigned and/or appear to have a mixed ancestry, despite estimates of substantial population differentiation. Thus, we suggest that population assignments of individuals should be viewed as tentative and that there should be agreement among different algorithms before assignments are applied in conservation or management. Further, we find no congruence between previously reported morphological differentiation and the sorting of microsatellite variation. Some introduced populations have retained much genetic variation while others have not, irrespective of morphology. Finally, we find alleles from the sympatric grey mongoose (Herpestes edwardsii) in one small Indian mongoose within the native range, suggesting an alternative explanation for morphological differentiation involving a shift in female preferences in allopatry. 相似文献
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Iago FerreiroArias Jorge Isla Pedro Jordano Ana BenítezLpez 《Ecology and evolution》2021,11(22):15520
- The partition of the ecological niche can enhance the coexistence of predators due to differences in how they exploit three main resources: food, space, and time, the latter being an axis that often remains unexplored.
- We studied niche segregation in a Mediterranean mesocarnivore community composed by Vulpes vulpes, Genetta genetta, Meles meles, and Herpestes ichneumon, addressing simultaneously different niche axes: the temporal, trophic, and spatial axes.
- We assessed temporal segregation between mesopredators and prey and between potential competitors, using camera trap data between 2018 and 2020 in a Mediterranean landscape in Southern Spain. We deployed camera traps in 35 stations in three sites with varying vegetation cover within Doñana National Park. We further examined the spatial overlap in activity centers and trophic preferences between potential competitors using diet information from studies performed in the study area.
- We found an overall temporal segregation between trophic generalist species, with species showing higher temporal overlap differing in their trophic preferences and/or showing limited spatial overlap. Furthermore, we observed an overall high overlap between the activity patterns of predators and their major prey in the area (the common genet vs. small mammals and the red fox vs. European rabbit).
- Our study suggests that coexistence of the different species that compose the mesocarnivore assemblage in Mediterranean landscapes can be facilitated by subtle differences along the three main niche axes, with temporal segregation being a most pronounced mechanism. Our findings reinforce the idea that the coexistence mechanisms underlying community structure are multidimensional.
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Francisco J. Vilella 《Biotropica》1998,30(1):120-125
Ecological aspects of the mongoose (Herpestes javanicus) were studied in the Luquillo Mountains, a rain forest region in eastern Puerto Rico. Information was obtained by removal trapping of mongoose from grids placed in tree plantations, colorado and tabonuco forests. Trapping efficiency was two mongoose per 100 trap-days, suggesting mongoose abundance is low in wet montane forests of Puerto Rico. Sex ratio was biased (2.6:1) in favor of males. Body masses of male mongoose inhabiting rain forests of the Luquillo Mountains were larger than those in dry forests at Guánica (P < 0.0001). Stomach contents from 18 mongoose were examined, animal matter comprised 75 percent of the total food items encountered. Of these, 33 percent were from vertebrates. The food items most frequently encountered were lizards (Anolis spp.), centipedes (Scolopendra spp.), and cockroaches (Blatellidae). 相似文献