?Phylogeography, a Growing Bridge? _ Patterns of genetic diversity and phylogeography in aridland rodents of Argentina

AGUSTINA A OJEDA

Simposio; II Meeting of Systematics, Biogeography, and Evolution (SBE); 2021

SBE (Systematics, Biogeography, and Evolution)

The genetic structure observed in various taxa can be explained, in part, as a biotic response to past climatic and geological changes. In this sense, phylogeography seeks to interpret intra and interspecific genetic diversity patterns, combining a geographic and phylogenetic framework to understand the historical demography and population structure. In this presentation I discuss the results of ongoing phylogeographic, and phylogenetic studies aimed to elucidate the evolutionary relationships of different lineages of Caviomorph and Cricetid Andean and lowland desert rodents. To evaluate phylogenetic relationships and the geographic distribution of genetic variation, mitochondrial DNA sequences (COI, Cit b, Control region) were analyzed in individuals from different populations throughout their distribution. Genetic distances were calculated, and phylogenetic analyses based on Maximum Likelihood were performed. Some species showed deep divergences, accompanied by an important geographic structuring, and genetically differentiated intraspecific lineages; while other species display a low molecular divergence but were accompanied by morphological and cytogenetic differences. The patterns of genetic divergence in some of the studied species suggest the presence of a complex of cryptic species, where local populations have been diverging in relative isolation for long periods of time, while others suggest a recent speciation event. Phylogeographic approaches are increasingly used in taxonomy and conservation, as they provide evidence for the delimitation of species and the detection of potential management units, which have implications for their genetics conservation.