Fine-scale biogeography: tidal elevation strongly affects population genetic structure and demographic history in intertidal fishes

Abstract

Numerous studies have demonstrated population genetic structuring in marine species, yet few have investigated the effect of vertical zonation on gene flow and population structure. Here we use three sympatric, closely related clinid species, Clinus cottoides, C. superciliosus and Muraenoclinus dor‐salis, to test whether zonation on South African intertidal rocky shores affects phylogeographic patterns. We show that the high‐shore restricted species has reduced gene flow and considerably higher FST val‐ues (FST= 0.9).