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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
4.
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
5.
J. E. D. Fox 《Economic botany》1971,25(3):221-233
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Structural localization of the sequence alpha 235-242 of the nicotinic acetylcholine receptor 总被引:1,自引:0,他引:1
M Criado V Sarin J L Fox J Lindstrom 《Biochemical and biophysical research communications》1985,128(2):864-871
Two monoclonal antibodies (mAb 254 and 255) were obtained against a synthetic peptide corresponding to the sequence 235-242 of the alpha-subunit of Torpedo acetylcholine receptor. These mAbs could bind to receptor in native membrane vesicles only when these vesicles were permeabilized, suggesting that the sequence alpha 235-242 is exposed on the cytoplasmic surface of the receptor. Further evidence for the cytoplasmic localization of this sequence was partial competition for binding between these mAbs and mAbs previously demonstrated to bind to the cytoplasmic part of the receptor. A model is proposed which accounts for all the experimental data obtained thus far on the transmembrane orientation of the subunit polypeptide chains. 相似文献
7.
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
8.
Danielle E. Haulsee Dewayne A. Fox Matthew W. Breece Tonya M. Clauss Matthew J. Oliver 《PloS one》2016,11(2)
We developed a long-term tagging method that can be used to understand species assemblages and social groupings associated with large marine fishes such as the Sand Tiger shark Carcharias taurus. We deployed internally implanted archival VEMCO Mobile Transceivers (VMTs; VEMCO Ltd. Nova Scotia, Canada) in 20 adult Sand Tigers, of which two tags were successfully recovered (10%). The recovered VMTs recorded 29,646 and 44,210 detections of telemetered animals respectively. To our knowledge, this is the first study to demonstrate a method for long-term (~ 1 year) archival acoustic transceiver tag implantation, retention, and recovery in a highly migratory marine fish. Results show low presumed mortality (n = 1, 5%), high VMT retention, and that non-lethal recovery after almost a year at liberty can be achieved for archival acoustic transceivers. This method can be applied to study the social interactions and behavioral ecology of large marine fishes. 相似文献
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Identification of actin-binding protein as the protein linking the membrane skeleton to glycoproteins on platelet plasma membranes 总被引:25,自引:0,他引:25
J E Fox 《The Journal of biological chemistry》1985,260(22):11970-11977
Platelets have previously been shown to contain a membrane skeleton that is composed of actin filaments, actin-binding protein, and three membrane glycoproteins (GP), GP Ib, GP Ia, and a minor glycoprotein of Mr = 250,000. The present study was designed to determine how the membrane glycoproteins were linked to actin filaments. Unstimulated platelets were lysed with Triton X-100, and the membrane skeleton was isolated on sucrose density gradients or by high-speed centrifugation. The association of the membrane glycoproteins with the actin filaments was disrupted when actin-binding protein was hydrolyzed by activity of the Ca2+-dependent protease, which was active in platelet lysates upon addition of Ca2+ in the absence of leupeptin. Similarly, activation of the Ca2+-dependent protease in intact platelets by the addition of a platelet agonist also caused the membrane glycoproteins to dissociate from the membrane skeleton. Affinity-purified actin-binding protein antibodies immunoprecipitated the membrane glycoproteins from platelet lysates in which actin filaments had been removed by DNase I-induced depolymerization and high-speed centrifugation. These results demonstrate that actin-binding protein links actin filaments of the platelet membrane skeleton to three plasma membrane glycoproteins and that filaments are released from their attachment site when actin-binding protein is hydrolyzed by the Ca2+-dependent protease within intact platelets during platelet activation. 相似文献