New paper: Phylogenomics of pike cichlids (Cichlidae: Crenicichla) and the rapid ecological speciati

In this new paper, we assess the pike cichlid phylogeny using Ultraconserved eletments (UCEs) as well as test the relationships and co-ancestry of five closely-related species (i.e., the Uruguay River species flock; URSF). Additionally, we quantify body and pharyngeal jaw shape of the URSF. We found that these species are well-supported genetic clusters, but that the relationships among them remain problematic, likely due to their recent diversification. In contrast, we found that these species exhibit highly species-specific body and pharyngeal jaw shape and associated specialized diets. We liken this small river-dwelling radiation to the infamous lake-dwelling groups of cichlids that rapidly arose in situ within lakes. The dramatic morphological and ecological differentiation despite shallow genetic divergence suggests that the selection that drove their ecological diversification likely played a central role during the proliferation of the URSF and we ultimately conclude that this radiation likely arose via ecological speciation.

I am grateful to my suite of fantastic collaborators that made this work possible and I look forward to continuing to study these fishes. In other words, there is more to come!

Burress, E.D., F. Alda, A. Duarte, M. Loureiro, J.W. Armbruster, and P. Chakrabarty. 2017. Phylogenomics of pike cichlids (Cichlidae: Crenicichla) and the rapid ecological speciation of an incipient species flock. Journal of Evolutionary Biology. doi: 10.1111/jeb.13196.