Polyploidy breaks speciation barriers in Australian burrowing frogs < i > Neobatrachus < /i >

We describe rapid speciation of diploidNeobatrachus species and show that the three independently originated polyploid species have tetrasomic or mixed inheritance. We document higher genetic diversity in tetraploids, resulting from widespread gene flow between the tetraploids, asymmetric inter-ploidy gene flow directed from sympatric diploids to tetraploids, and isolation of diploid species from each other. We also constructed models of ecologically suitable areas for each species to investigate the impact of climate on differing ploidy levels. These models suggest substantial change in suitable areas compared to past climate, which correspond to population genomic estimates of demographic histories. We propose thatNeobatrachus diploids may be suffering the early genomic impacts of climate-induced habitat loss, while tetraploids appear to be avoiding this fate, possibly due to widespread gene flow. Finally, we demonstrate thatNeobatrachus is an attractive model to study the effects of ploidy on the evolution of adaptation in animals.
Source: PLoS Genetics - Category: Genetics & Stem Cells Authors: Source Type: research