Mitochondrial DNA genetic diversity and phylogeography of Laternula elliptica in the Western Antarctic Peninsula

Student: 
Eleonora Cariolato
Room: 
room 1
session: 
Session 1, August 26, 09:00-10:30

The Antarctic continent is surrounded by the Southern Ocean that thanks to its Polar fronts and the Antarctic Circumpolar Current isolates Antarctica. Consequentially, the Antarctic biota is highly endemic and biodiverse. However, current climate changes are threatening the Southern Ocean ecosystem. Phylogeography and population genetics that investigate the demographic history during past climatic events could provide insights into climate change future scenarios. This study investigates the phylogeography and genetic diversity of the Antarctic spawning bivalve Laternula elliptica in the West Antarctic Peninsula, applying mtDNA regions as genetic markers to estimate genetic distances within/between populations and to build haplotype networks. The results show low genetic distances both within and between populations with no obvious biogeographical pattern in the geographic region, suggesting connectivity between populations. The genetic signature of refugia is difficult to interpret from the haplotype networks; three hypotheses have been formulated that would describe L. elliptica’s response to past climatic changes, and possible refugia habitats during glaciations. The limited sample size of this study calls for further studies on L. elliptica’s phylogeography and population genetics to support these preliminary results, possibly including samples from additional Antarctic regions, more equal sampling design, and the development of more suitable genetic markers.