title: Contrasting genetic diversity and population structure among three sympatric Madagascan shorebirds: parallels with rarity, endemism, and dispersal.
abstract: Understanding the relative contributions of intrinsic and extrinsic factors to population structure and genetic diversity is a central goal of conservation and evolutionary genetics. One way to achieve this is through comparative population genetic analysis of sympatric sister taxa, which allows evaluation of intrinsic factors such as population demography and life history while controlling for phylogenetic relatedness and geography. We used ten conserved microsatellites to explore the population structure and genetic diversity of three sympatric and closely related plover species in southwestern Madagascar: Kittlitz's plover (Charadrius pecuarius), white-fronted plover (C. marginatus), and Madagascar plover (C. thoracicus). Bayesian clustering revealed strong population structure in the rare and endemic Madagascar plover, intermediate population structure in the white-fronted plover, and no detectable population structure in the geographically widespread Kittlitz's plover. In contrast, allelic richness and heterozygosity were highest for the Kittlitz's plover, intermediate for the white-fronted plover and lowest for the Madagascar plover. No evidence was found in support of the "watershed mechanism" proposed to facilitate vicariant divergence of Madagascan lemurs and reptiles, which we attribute to the vagility of birds. However, we found a significant pattern of genetic isolation by distance among populations of the Madagascar plover, but not for the other two species. These findings suggest that interspecific variation in rarity, endemism, and dispersal propensity may influence genetic structure and diversity, even in highly vagile species.
authors: Department of Animal Behaviour, Bielefeld University Morgenbreede 45, 33615, Bielefeld, Germany.
authors: Luke J
authors: LJ
authors: Eberhart-Phillips
authors: Department of Animal Behaviour, Bielefeld University Morgenbreede 45, 33615, Bielefeld, Germany.
authors: Joseph I
authors: JI
authors: Hoffman
authors: Biodiversity and Ecological Processes Group, Cardiff School of Biosciences, Cardiff University Cardiff, CF10 3AX, U.K.
authors: Edward G
authors: EG
authors: Brede
authors: Department of Animal Biology, University of Toliara PO Box 185, Toliara, Madagascar.
authors: Sama
authors: S
authors: Zefania
authors: Department of Animal Behaviour, Bielefeld University Morgenbreede 45, 33615, Bielefeld, Germany.
authors: Martina J
authors: MJ
authors: Kamrad
authors: Department of Animal Behaviour, Bielefeld University Morgenbreede 45, 33615, Bielefeld, Germany ; Biodiversity Lab, Department of Biology and Biochemistry, University of Bath Bath, BA2 7AY, U.K.
authors: Tamás
authors: T
authors: Székely
authors: Biodiversity and Ecological Processes Group, Cardiff School of Biosciences, Cardiff University Cardiff, CF10 3AX, U.K.
authors: Michael W
authors: MW
authors: Bruford
keywords: Abundance; dispersal; endemism; gene flow; genetic drift; shorebird