top of page
Environmental drivers of evolution for Antarctic terrestrial organisms
To understand the evolution of the current Antarctic plants and animals, we need to determine how and if they survived recent glacial maxima and how and if they have moved into and out of the region.
This PhD project is investigating:
What drives diversity in Antarctic terrestrial multicellular eukaryotes?
What are the key environmental drivers of diversity and connectivity?
Do geothermal areas provide long-term refugia?
We are using exon-capture genomic analyses of mosses, combined with spatial environmental modelling, to test the influence of environmental factors such as temperature, elevation and wind on patterns of diversity and connectivity. Exon-capture baits have been developed for 3600 loci for Bryum pseudotriquetrum, and these appear to work for diverse Antarctic moss genera. Herbarium samples are available from across Antarctica and other southern continents, but fresh samples will work best for genomic analyses.
Biological evidence indicates that much of Antarctica’s terrestrial biota has survived in situ on the continent for millions of years. Geothermal areas could have created long-term ice-free terrain in Antarctica, thereby helping life to survive throughout Pleistocene ice ages. This hypothesis has, however, yet to be thoroughly tested. Diversity patterns in terrestrial eukaryotes will be investigated over local (10s –100s km) and continental scales and at both intraspecific (mosses via exon capture) and interspecific (soil eDNA metabarcoding) levels. We hypothesise that, if geothermal areas were glacial refugia, diversity will be highest close to such areas, and will decrease further away.
Modified from Carson et al., 2014.
Small-scale (10s –100s kms) sampling to test the role of geothermal areas in supporting biodiversity. Bottom panel: heat flow is unusually high in some of these areas, due to radiogenic decay of granites (figure from Carson et al. 20144). We predict these ‘hot’ sites (red / orange dots) will support higher diversity within and among species than nearby ‘cold’ sites (blue dots).
Can you help with sample collection / access to samples in existing collections? Please get in touch! :)
Existing samples vs tentative sampling sites (yellow and red regions, respectively).
bottom of page