نتایج جستجو برای: gazella marica
تعداد نتایج: 458 فیلتر نتایج به سال:
Modeling of ecological connectivity across landscape is important for understanding a wide range of ecological processes. Modeling ecological connectivity between habitats and incorporating these models into conservation planning require quantifying the effect of spatial patterns of landscape on the degree of habitats connectivity. Recently, concepts from electrical circuit theory have been ad...
1. Theory predicts that small grazers are regulated by the digestive quality of grass, while large grazers extract sufficient nutrients from low-quality forage and are regulated by its abundance instead. In addition, predation potentially affects populations of small grazers more than large grazers, because predators have difficulty capturing and handling large prey. 2. We analyse the spatial d...
Published studies of wild vertebrate populations have almost universally reported positive associations between genetic variation measured at microsatellite loci and fitness, creating the impression of ubiquity both in terms of the species and the traits involved. However, there is concern that this picture may be misleading because negative results frequently go unpublished. Here, we analyse t...
Vegetation is sparsely distributed over Antarctica's ice-free ground, and distinct plant communities are present in each of the continent's 15 recently identified Antarctic Conservation Biogeographic Regions (ACBRs). With rapidly increasing human activity in Antarctica, terrestrial plant communities are at risk of damage or destruction by trampling, overland transport, and infrastructure constr...
Differences in level of herbivory can select for local adaptation and genetic differentiation of plant populations in different environments. Mean bulb depth of the desert lily Pancratium sickenbergeri, differs considerably among populations differing in the level of herbivory by the dorcas gazelle. The gazelle digs in the sand to remove most of the bulb of the lily. Deeper bulbs have less mate...
Procapra przewalskii (Büchner, 1891), commonly called Przewalski’s gazelle, is polytypic with 1 of the 2 subspecies (P. p. diversicornis) likely extinct. The species now occurs only in the Qinghai Lake region in northeastern Qinghai Province, western China, and predominately inhabits semiarid grassland steppe, stable sand dunes, and the desert–shrub ecotone between them. Numbers and distributio...
Emerging Bayesian analytical approaches offer increasingly sophisticated means of reconstructing historical population dynamics from genetic data, but have been little applied to scenarios involving demographic bottlenecks. Consequently, we analysed a large mitochondrial and microsatellite dataset from the Antarctic fur seal Arctocephalus gazella, a species subjected to one of the most extreme ...
There is growing evidence of escalating wildlife losses worldwide. Extreme wildlife losses have recently been documented for large parts of Africa, including western, Central and Eastern Africa. Here, we report extreme declines in wildlife and contemporaneous increase in livestock numbers in Kenya rangelands between 1977 and 2016. Our analysis uses systematic aerial monitoring survey data colle...
Eight wooden objects were found at Ohalo II, a submerged and well-preserved site in the Sea of Galilee, Israel. The fisher-hunter-gatherers' site has been radiometrically dated to 22,500-23,500 (cal BP) with 45 assays read by four laboratories. The wooden objects were found on brush-hut floors. They include a bark plank with polish and use signs, pencil-shaped specimens with longitudinal shavin...
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