Intraspecific divergence, assortative mating and hybridisation in the Amazonian frog, Allobates femoralis
thesisposted on 28.03.2022, 19:17 authored by Elayna Truszewski
The processes that have driven species diversity in the Amazon Basin remain unknown or in contention for many taxa. For the brilliant-thighed frog, Allobates femoralis, I evaluated two competing variance-based hypotheses explaining the diversification of Amazonian biota; the riverine barrier hypothesis and the Pleistocene refugia hypothesis. I also investigated whether assortative mating maintains the barrier between distinct genetic lineages when physical contact is restored. Using fragments of 16S rRNA and cytb mtDNA sourced from GenBank, I conducted a time-calibrated phylogenic reconstruction using the Bayesian approach implemented in the *BEAST software. Node divergence dates and patterns of intraspecific divergence were found to be strongly associated with river locations, and therefore, compatible with the riverine barrier hypothesis. At several locations, however, contact zones occur between genetically distinct lineages of A. femoralis. In order to test whether assortative mating explains the lack of genetic recombination, I analysed mate choice in a population where individuals with different call types occur in sympatry. A data set of 8067 single nucleotide polymorphisms and mtDNA (16S) sequences revelealed significant genetic partitioning between colour morphs, but not call type. These results provide a new insight into anuran mating systems, especially in respect to the traits which control mate choice.