Evolution of foraging behaviour : deep intra-generic genetic divergence between territorial and non-territorial southern African patellid limpets

This paper is adapted from part of a dissertation submitted by KLM for the degree of Doctor of Philosophy at Rhodes University, South Africa.Southern Africa is a biodiversity hotspot of patellid limpets, with three genera (Helcion, Cymbula and Scutellastra) identified and described in the region. Scutellastra is the most diverse and most frequently studied of these and, along with Cymbula, includes species with territorial and non-territorial foraging behaviours. We used three mitochondrial markers (12S rRNA, 16S rRNA and COI) and one nuclear marker (ATPSβ intron) to assess evolutionary relationships among species of Cymbula and Scutellastra with these two foraging behaviours and to identify which foraging mode is the more ancient. Maximum Likelihood and Bayesian Inference phylogenetic analyses revealed that the species sharing a foraging type are monophyletic in both genera. Territoriality is a derived character, as the clades with this foraging type are nested within a tree that otherwise comprises non-territorial taxa. These include Helcion, which was recovered as sister to the Cymbula/Scutellastra clade, and the next basal genus, Patella, which is ancestral to all southern African patellogastropods. Deep genetic divergence between the two foraging traits reflects strong adaptive effects of resource partitioning in the evolution of southern African patellid limpets.The South African Research Chairs Initiative of the Department of Science and Technology, National Research Foundation (NRF) of South Africa, and Rhodes University, and also funded in part through an NRF grant to NPB (Unique Grant Number 206119).http://www.elsevier.com/locate/ympev2018-12-01hj2018Plant Production and Soil Scienc