Phylogeography of the southern skua complex—rapid colonization of the southern hemisphere during a glacial period and reticulate evolution

Abstract

a b s t r a c tWhilst we have now a good understanding how past glaciation influenced species at the northern hemisphere, our knowledge of patterns and modes of speciation is far more limited for the southern hemisphere. We provide mtDNA based data on the phylogeography of a circumpolar distributed southern hemisphere seabird group-the southern skua complex (Catharacta spp.). Diversification of southern skuas dates between 210,000 yBP and 150,000 yBP and coincides with a glacial spanning 230,000-140,000 yBP. Skuas most likely first inhabited the Antarctic continent, in the course of global cooling and increasing glaciation spread to the sub-antarctic islands and Tristan da Cunha and finally colonized Patagonia and the Falkland Islands at the glacial maximum. Despite significant differences between taxa most populations still exchange genes with neighboring populations of other taxa and speciation is incomplete.

Comparative phylogeography of the Yellow River schizothoracine fishes (Cyprinidae): Vicariance, expansion, and recent coalescence in response to the Quaternary environmental upheaval in the Tibetan Plateau

“…Generally, most species with high dispersal potential lack sharp geographical differentiation (Roman and Palumbi, 2004;Ritz et al, 2008), and the headwater taxa are potentially highly susceptible to river capture (Koblmüller et al, 2008). Therefore, for Sy.…”

Diet of South Polar Skua Chicks in Two Areas of Sympatry with Brown Skua

“…In particular, Brown Skua (Stercorarius antarcticus) and South Polar Skua (S. maccormicki) (hereafter Antarctic skuas) are top predators that nest in subantarctic islands and the Antarctic (Ritz et al 2006(Ritz et al , 2008. When breeding in sympatry, Brown Skuas monopolize the terrestrial feeding resources (i.e., penguin colonies) while South Polar Skuas feed at sea (i.e., fish) (Montalti et al 2009;Graña Grilli and Montalti 2014).…”

At-sea abundance and distribution of skuas and jaegers (Charadriiformes: Stercorariidae) at coastal waters off central Chile

“…The Stercorariidae constitutes a small, distinctive family of seven kleptoparasitic seabird species all now regarded as within the genus Stercorarius (Remsen et al 2013), although much debate exists about their systematics; sometimes, more species and a second genus are recognized within the family (Cohen et al 1997;Braun and Brufield 1998;Ritz et al 2008;Chu et al 2009). The family comprises the larger and mostly Brown skuas and the smaller, more agile jaegers.…”