The Siler Lab is attending the Society for the Study of Amphibians and Reptiles (SSAR) annual meeting in Lawrence, KS on July 30-Aug. 2, 2015. See below for titles and abstracts:
Preliminary screening of natural history collections for historical presence of amphibian infection disease in Oklahoma
by Rachel L. Flanagan, Jessa L. Watters, Cameron D. Siler
Amphibian populations are declining all over the world, with one-third of the species facing extinction. Chytridiomycosis is one example of an amphibian infectious disease caused by the fungus Batrachochytrium dendrobatidis (Bd), which is contributing to anuran declines. This fungus embeds itself into the keratinized structures of amphibians causing loss of skin function and eventually death. In Oklahoma, there have been few studies done on amphibians contaminated with chytrid. As a result, the Herpetology Department at the Sam Noble Oklahoma Museum of Natural History, has begun a statewide survey for Bd in Oklahoma. In order to determine the historical presence of Bd in the state, I have swabbed over 600 vouchered amphibian specimens collected in Oklahoma from 1924 to 2014 to determine whether any museum specimens were infected in life, as well as the temporal distribution of disease in the state. Given the documented presence of Bd at a few sites in the state, we expect to discover the disease within other populations of native amphibians in Oklahoma. The results will provide a baseline dataset that can be applied to continued conservation efforts in collaboration with the Oklahoma Department of Wildlife Conservation.
The Molecular Phylogenetics and Biogeography of the Widespread Skink Genus Lygosoma Hardwicke & Gray 1827
by Elyse S. Freitas and Cameron D. Siler
The skink genus Lygosoma comprises 31 species ranging from the Philippines, the Indian Subcontinent, Southeast Asia, and sub-Saharan Africa. However, despite its wide distribution, there are few studies investigating phylogenetic relationships and the biogeographic history of this genus, and many relationships among species in Lygosoma remain unresolved. Recent studies resurrected the generic names Lepidothyris, Mochlus, and Riopa for African and Indian members of the genus, but the composition and phylogenetic position of these genera within the larger Lygosoma complex is not fully resolved. Using mitochondrial and nuclear loci, we generated a large phylogenetic dataset of Lygosoma sensu lato to assess species relationships and diversity within the genus, and evaluate biogeographic patterns across such an expansive range. Results suggest that there is substantial cryptic diversity within the genus, especially within broadly distributed species from Indochina and the Thai-Malay Peninsula. Species from India form a monophyletic group within a larger Indochina and Thai-Malay clade. Additionally the recently resurrected African genera, Lepidothyris and Mochlus, render Lygosoma paraphyletic. This study is the first large-scale investigation of Lygosoma and provides a critical context for future studies of the evolutionary history of the genus.
Community Assembly of a Morphologically Diverse Skink Genus (Brachymeles)
by Nicholas A. Huron, Rafe M. Brown, Cameron D. Siler
Many factors contribute to the distribution of species, including habitat requirements, morphology, and evolutionary history, which subsequently facilitate regional community composition. Regional differences among these factors are important for understanding the composition of communities of closely related species. My thesis research will integrate studies of phylogenetic dispersion with ecological niche modeling to investigate the distribution patterns of burrowing skinks in the genus Brachymeles across the Philippines. Over 40 species occur in the archipelago, displaying a full spectrum of body forms, from pentadactyl to limbless species. Interestingly, species throughout the Philippines occur in sympatric communities of three to five lineages, each with disparate morphologies (e.g., large pentadactyl, small non-pentadactyl, and limbless species)—to date, no exceptions to this pattern have been observed. In this study, I test for phylogenetic patterns of community assembly to determine the role of evolutionary history in explaining sympatric distributions. Support for either phylogenetic overdispersion or clustering can provide insight into patterns of diversification that have resulted in community composition (e.g., phylogenetic clustering can indicate community patterns driven by dispersal versus in situ diversification). Additionally, ecological niche modeling will be employed to ascertain the degree of niche overlap that exists among species within a community. Interspecific niche differentiation within communities would provide support for abiotic factors of the environment playing a role in community assembly. Conversely, strong niche overlap may support ecological niche similarity within communities; implying differences in other factors, such as biotic interactions, may affect species’ distributions. This study will disentangle regional community assembly patterns and serve as a key step in determining the factors that are involved in the evolution of unique patterns of morphology that differentiate species of Brachymeles.
Development of New Collaborative and Citizen Science Projects for Amphibian Infectious Disease Sampling in Oklahoma
by Jessa L. Watters, Stacey Sekscienski, and Cameron D. Siler
The Sam Noble Museum Herpetology Department has joined with the Oklahoma City Zoo to investigate seasonal patterns of infectious amphibian diseases in Oklahoma. Multiple sites were selected in central Oklahoma as focal locations to monitor recognized amphibian pathogens, particularly chytrid fungus (Batrachochytrium dendrobatidis; Bd) and ranaviruses. One of the sample sites is within the zoo grounds where a Bd positive sample has recently been documented, representing one of only four sites to have been screened in the state. Complimenting our three-year, statewide disease assessment with the Oklahoma Department of Wildlife Conservation, the Oklahoma City Zoo and the Sam Noble Museum are working to develop a new citizen science program that will allow K–12 teachers and students across Oklahoma to participate in disease monitoring by swabbing live frogs and collecting water samples to screen for environmental DNA (eDNA) markers of focal pathogens. Each kit will include swabs, vials, instructions, identification guides to Oklahoma frogs, shipping labels, and curriculum guides. These kits will be provided to science teachers around the state free of charge via the mail or direct pick-up. Following kit return, samples will be processed and analyzed, with results shared publicly online as well as provided directly to participants.
Hope to see you all there!