High-elevation adaptation of amphibians and reptiles and its genetic basis

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My research aims to understand the process of adaptation in natural populations using the elevational gradient as a study system. For the next five years, my specific objectives include detecting genetic and phenotypic variations of a common toad (Bufo gargarizans) along elevational gradients, establishing associations between them, and understanding how these variations may have contributed to the adaptation process. My primary approach will be population-level comparative analysis. Bufo gargarizans is a common toad in Tibet with a large elevational distribution range (0-3800 m). We have located three sampling transects. Each transect has a minimum elevational difference of 2000 m and a maximum straight line distance of 50 km. Recently, we have successfully sequenced its genome. I will conduct a population genomic analysis, identify putative adaptive variants, and address fundamental questions of genetic adaptation. Using genome re-sequencing, we will gather genome data along these transects. The elevational gradient design will facilitate the identification of putative adaptive variants. These variants will then be subject to functional analysis and association studies to phenotypic variations. Furthermore, we will assess whether certain classes of variants are particularly important in adaptive evolution (e.g. particular pathways, regulatory mutations), and test for evidence of co-evolution or constraints among genes. I will detect phenotypic variations, including morphological, behavioural, physiological and life history traits, along these transects. Currently, we are focusing on morphology of the brain, sensory organs, and locomotion related traits, as well as behavioural and physiological traits that may interact with life history traits (the pace-of-life syndrome). Ultimately, we will establish association between genetic variations and phenotypic variations. I will also apply between-species comparative analysis to explore convergence and parallelism between high-elevation amphibians and other vertebrates (e.g. Phrynocephalus lizards, deer mice, human). This will allow us to put our research findings into a larger context and to generate widely applicable hypotheses. Our integrative analysis of variations at multiple hierarchical levels will yield insights into causes and consequences of adaptive genetic changes and the genetic architecture underlying complex phenotypic traits.