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Impacts of climate change on Cunningham's skink (Egernia cunninghami)
thesisposted on 2022-03-28, 22:59 authored by Benjamin Yeboah Ofori
Climate change has become a mainstay conservation research topic because of the substantial threat it poses to global biodiversity. The capacity of species to disperse to track the movement of their climate niches, or to adapt in situ to novel climates through microevolution, will determine their persistence under climate change. Yet, studies assessing the impacts of climate change on biodiversity rarely account for species' dispersal and evolutionary potential. In this thesis, I employ population genomics, and species distribution and landscape connectivity models to assess the potential responses of a philopatric species, Cunningham's skink (Egernia cunninghami), to climate change. Genetic data revealed strong population structuring, and different spatial patterns of putatively neutral SNPs versus those under divergent selection. I found a significant positive association between SNPs under divergent selection and temperature. Results suggest that the natural dispersal rate of Cunningham's skink may be insufficient to track shifts in climate zones, irrespective of landscape connectivity. Similar results were obtained by incorporating realistic estimates of dispersal and landscape connectivity into species distribution models, i.e. most populations of E. cunninghami may not have adequate dispersal capabilities to track climate change. However, combining measures of exposure, sensitivity and adaptive capacity to assess the vulnerability of E. cunninghami and other Australian lizards to climate change revealed that some lizards, including E. cunninghami, may have sufficient adaptive potential (micro-evolutionary and plastic responses) to cope with climate change.