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The Asian Tree Toad genus Pedostibes, as currently understood, exhibits a conspicuously disjunct distribution, posing several immediate questions relating to the biogeography and taxonomy of this poorly known group. The type species, P. tuberculosus and P. kempi, are known only from India, whereas P. hosii, P. rugosus, and P. everetti are restricted to Southeast Asia. Several studies have shown that these allopatric groups are polyphyletic, with the Indian Pedostibes embedded within a primarily South Asian clade of toads, containing the genera Adenomus, Xanthophryne, and Duttaphrynus. Southeast Asian Pedostibes on the other hand, are nested within a Southeast Asian clade, which is the sister lineage to the Southeast Asian river toad genus Phrynoidis. We demonstrate that Indian and Southeast Asian Pedostibes are not only allopatric and polyphyletic, but also exhibit significant differences in morphology and reproductive mode, indicating that the Southeast Asian species’ are not congeneric with the true Pedostibes of India. As a taxonomic solution, we describe a new genus, Rentapia
gen. nov. to accommodate the Southeast Asian species. 相似文献
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The distribution of grooming and touching behaviours was recorded in a group of captive ring-tailed lemurs. Grooming was found
to be performed chiefly by older, higher ranking animals; touching (i.e., “reach out and touch” behaviour) was directed primarily
by younger, low ranking animals to older, high ranking individuals. It is suggested that such touching is a submissive gesture
in this species. 相似文献
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Sandra L. Almeyda Zambrano Eben N. Broadbent Sam Shanee Noga Shanee Anneke Deluycker Michael Steinberg Scott A. Ford Alma Hernndez Jaramillo Robin Fernandez‐Hilario Carolina Lagos Castillo Angelica M. Almeyda Zambrano 《American journal of primatology》2019,81(8)
Habitat loss is one of the main threats to wildlife. Therefore, knowledge of habitat use and preference is essential for the design of conservation strategies and identification of priority sites for the protection of endangered species. The yellow‐tailed woolly monkey (Lagothrix flavicauda Humboldt, 1812), categorized as Critically Endangered on the IUCN Red List, is endemic to montane forests in northern Peru where its habitat is greatly threatened. We assessed how habitat use and preference in L. flavicauda are linked to forest structure and composition. The study took place near La Esperanza, in the Amazonas region, Peru. Our objective was to identify characteristics of habitat most utilized by L. flavicauda to provide information that will be useful for the selection of priority sites for conservation measures. Using presence records collected from May 2013 to February 2014 for one group of L. flavicauda, we classified the study site into three different use zones: low‐use, medium‐use, and high‐use. We assessed forest structure and composition for all use zones using 0.1 ha Gentry vegetation transects. Results show high levels of variation in plant species composition across the three use zones. Plants used as food resources had considerably greater density, dominance, and ecological importance in high‐use zones. High‐use zones presented similar structure to medium‐ and low‐use zones; thus it remains difficult to assess the influence of forest structure on habitat preference. We recommend focusing conservation efforts on areas with a similar floristic composition to the high‐use zones recorded in this study and suggest utilizing key alimentation species for reforestation efforts. 相似文献
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Background
With increasing computer power, simulating the dynamics of complex systems in chemistry and biology is becoming increasingly routine. The modelling of individual reactions in (bio)chemical systems involves a large number of random events that can be simulated by the stochastic simulation algorithm (SSA). The key quantity is the step size, or waiting time, τ, whose value inversely depends on the size of the propensities of the different channel reactions and which needs to be re-evaluated after every firing event. Such a discrete event simulation may be extremely expensive, in particular for stiff systems where τ can be very short due to the fast kinetics of some of the channel reactions. Several alternative methods have been put forward to increase the integration step size. The so-called τ-leap approach takes a larger step size by allowing all the reactions to fire, from a Poisson or Binomial distribution, within that step. Although the expected value for the different species in the reactive system is maintained with respect to more precise methods, the variance at steady state can suffer from large errors as τ grows. 相似文献10.
The cell cycle modulated glycoprotein GP115 is one of the major yeast proteins containing glycosylphosphatidylinositol 总被引:11,自引:0,他引:11
The cell cycle modulated protein gp115 (115 kDa, isoelectric point about 4.8-5) of Saccharomyces cerevisiae undergoes various post-translational modifications. It is N-glycosylated during its maturation along the secretory pathway where an intermediary precursor of 100 kDa (p100), dynamically related to the mature gp115 protein, is detected at the level of endoplasmic reticulum. Moreover, we have shown by the use of metabolic labeling with [35S]methionine, [3H]palmitic acid and myo-[3H]inositol combined with high resolution two-dimensional gel electrophoresis and immunoprecipitation with a specific antiserum, that gp115 is one of the major palmitate- and inositol-containing proteins in yeast. These results, and the susceptibility of gp115 to phosphatidylinositol-specific phospholipase C treatment strongly indicate that gp115 contains the glycosylphosphatidylinositol (GPI) structure as membrane anchor domain. The two-dimensional analysis of the palmitate- and inositol-labeled proteins has also allowed the characterization of other polypeptides which possibly contain a GPI structure. 相似文献