Title: Population genetics of the lichen species Umbilicaria aprina, Umbilicaria decussata and Buellia frigida along a latitudinal gradient in the Ross Sea region
A latitudinal change in population genetics of selected lichen species was conducted to determine whether these lichen communities have spread along a latitudinal gradient from northern latitudes during the reasonably recent time period of the modern ice sheet or are relics from refugia, such as nunatuks, which have existed since the time of Gondwanaland. Samples of Umbilicaria aprina, Umbilicaria decussata and Buellia frigidawere collected from Igloo Spur at Cape Crozier, Mt Falconer in the Taylor Valley, Linnaeus Terrace in the Asgard Range, the Nussbaumriegel in the Taylor Valley, Gondwana and Granite Harbour for analysis in the lab to be able to compare the origin of dispersal and choice of algal partner over a wide latitudinal gradient. Several samples were retained on rock surfaces for identification purposes and as herbarium voucher specimen. Fluorescence analyses were conducted to ascertain photosynthetic activity over time as well as under different light conditions. The genetic relationship between populations and the determination of photobiont specificity in lichens was determined.