Lineage and ecomorphological diversification of burrowing snakes

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Snakes are a large radiation (ca. 4,000 species) of reptiles that evolved from lizard ancestors. Although the early evolutionary history of snakes is hotly debated, the remarkable transition to an elongated, limbless body form is generally thought to have evolved as an adaptation to a fossorial (burrowing) lifestyle. Life in soil imposes several, severe functional constraints on morphology and this has led to the view that limbless, headfirst burrowers are less likely to undergo rapid or adaptive radiation. Surprisingly, very few studies have explored the ecomorphological diversification of any major extant burrowing snake lineage, despite implications for understanding evolution in soils (including the possible origin of snakes). SOILRAD will trace the diversification of lineages and the adaptive possibilities of ecomorphology in Uropeltoidea, a major lineage of soil-dwelling snakes with great diversity in body and hea shape. In SOILRAD, I will explore uropeltoid diversification through three Research Objectives: (1.) apply 3-dimensional geometric morphometrics to microCT data from the huge collection of museum specimens at NHM, to quantify and identify the main axes of variation in skeletal morphology (skull, mandible and 'neck' vertebrae); (2.) use ancient DNA and Next-Generation sequencing techniques to reconstruct a more-complete evolutionary tree of Uropeltoidea; and (3.) assess rates and modes of lineage and ecomorphological diversification, and test hypotheses of adaptive radiation. SOILRAD will produce the most comprehensive phylogenetic hypothesis and first extensive quantitative data on uropeltoid osteology, and first detailed assessment of diversification in any major lineage of burrowing snakes. Through SOILRAD, I will be trained in CT imaging, 3D morphometrics, ancient DNA methods, museum collection management, public engagement and other professional skills that will establish me as a potential research-group leader in evolutionary biology research.