Data from: Understanding the mechanisms of anti-tropical divergence in the seabird White-faced Storm-petrel (Procellariiformes: Pelagodroma marina) using a multi-locus approach

Analytical methods that apply coalescent theory to multi-locus data have improved inferences of demographic parameters that are critical to understanding population divergence and speciation. In particular, at the early stages of speciation it is important to implement models that accommodate conflicting gene trees, and benefit from the presence of shared polymorphisms. Here, we employ eleven nuclear loci and the mitochondrial control region to investigate the phylogeography and historical demography of the pelagic seabird White-faced Storm-petrel (Pelagodroma marina) by sampling sub-species across its anti-tropical distribution. Groups are all highly differentiated: global mitochondrial Φst = 0.89 (P < 0.01) and global nuclear Φst varies between 0.22 and 0.83 (all P < 0.01). The complete lineage sorting of the mitochondrial locus between hemispheres is corroborated by roughly half of the nuclear genealogies, suggesting a long-term anti-tropical divergence in isolation. Coalescent-based estimates of demographic parameters suggest that hemispheric divergence of P. marina occurred approximately 840,000 ya (95% HPD 582,000-1,170,000), in the absence of gene flow, and divergence within the Southern Hemisphere occurred 190,000ya (95% HPD 96,000 – 600,000), both likely associated with the profound palaeo-oceanographic changes of the Pleistocene. A fledgling sampled in St Helena (tropical South Atlantic) suggests recent colonization from the Northern Hemisphere. Despite the great potential for long-distance dispersal, P. marina anti-tropical groups have been evolving as independent, allopatric lineages, and divergence is likely maintained by philopatry coupled with asynchronous reproductive phenology and local adaptation.