We investigated the hemotoxic effects of three North American pit vipers in healthy human donor blood. Using experiments focusing on platelet and red blood cell activity, we found differential effects of these venoms on these cellular components. Platelet aggregation was most induced by C.
View Article and Find Full Text PDFOrganismal interactions drive the accumulation of diversity by influencing species ranges, morphology, and behavior. Interactions vary from agonistic to cooperative and should result in predictable patterns in trait and range evolution. However, despite a conceptual understanding of these processes, they have been difficult to model, particularly on macroevolutionary timescales and across broad geographic spaces.
View Article and Find Full Text PDFA new species of skink, Trachylepis gonwouoi sp. nov. is described from Cameroon and the Republic of the Congo.
View Article and Find Full Text PDFBackground: The Indian Tectonic Plate split from Gondwanaland approximately 120 MYA and set the Indian subcontinent on a ~ 100 million year collision course with Eurasia. Many phylogenetic studies have demonstrated the Indian subcontinent brought with it an array of endemic faunas that evolved in situ during its journey, suggesting this isolated subcontinent served as a source of biodiversity subsequent to its collision with Eurasia. However, recent molecular studies suggest that Eurasia may have served as the faunal source for some of India's biodiversity, colonizing the subcontinent through land bridges between India and Eurasia during the early to middle Eocene (~35-40 MYA).
View Article and Find Full Text PDFWe describe two new species of morphologically cryptic monitor lizards (genus Varanus) from the Philippine Archipelago: Varanus dalubhasa sp. nov. and V.
View Article and Find Full Text PDFWe utilize robust geographical genetic sampling, a multilocus dataset, a new synthesis of numerous fossil calibration points, a time-calibrated phylogeny, and the Dispersal-Extinction-Cladogenesis model to test the prediction that widespread Southeast Asian water monitor species initially diversified on the Asian mainland and subsequently invaded the island archipelagos of the Philippines, Sundaland, and Wallacea. Our results strongly contradict these expectations and instead infer an initial water monitor radiation of range-restricted but highly divergent evolutionary lineages (now recognized as endemic species) in one archipelago around 3.6 mya, followed by an out-of-the-Philippines reinvasion of the mainland (2.
View Article and Find Full Text PDFWe provide the first report on the herpetological biodiversity (amphibians and reptiles) of the northern Sierra Madre Mountain Range (Cagayan and Isabela provinces), northeast Luzon Island, Philippines. New data from extensive previously unpublished surveys in the Municipalities of Gonzaga, Gattaran, Lasam, Santa Ana, and Baggao (Cagayan Province), as well as fieldwork in the Municipalities of Cabagan, San Mariano, and Palanan (Isabela Province), combined with all available historical museum records, suggest this region is quite diverse. Our new data indicate that at least 101 species are present (29 amphibians, 30 lizards, 35 snakes, two freshwater turtles, three marine turtles, and two crocodilians) and now represented with well-documented records and/or voucher specimens, confirmed in institutional biodiversity repositories.
View Article and Find Full Text PDFAs humans continue to explore the last uncharted regions of the planet, discoveries of previously unknown species of large vertebrates have become infrequent. Here, we report on the discovery of a spectacular new species of giant, secretive, frugivorous, forest monitor lizard (Genus: Varanus) from the forests of the northern Philippines. Using data from morphology and mitochondrial and nuclear DNA sequences, we demonstrate the taxonomic distinctiveness of this new 2 m long species and provide insight into its historical biogeography and systematic affinities.
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