Comparative Phylogeography of Pteropus samoensis and P. tonganus (Pteropodidae: Chiroptera) in the South Pacific

Abstract

Pteropids are large, highly mobile bats that are distributed widely across islands of the Pacific and Indian Oceans, southern Asia, and Australia. Dispersal behaviors and colonization patterns of pteropid species among oceanic islands are poorly known. In the southern Pacific, Pteropus samoensis and P. tonganus have partially overlapping ranges, existing in sympatry on the Samoan and Fijian archipelagos. These species exhibit differences in morphology and roosting behavior, with P. samoensis being smaller and tending to roost solitarily or in small groups. Here, we use genetic data to explore whether these species also exhibit differences with regard to patterns of population genetic structure within and between these archipelagos. Phylogenetic analyses of mitochondrial DNA are consistent with earlier morphological recognition of different subspecies of P. samoensis on the Samoan vs. Fijian archipelagos. Patterns of mtDNA haplotype sharing suggest that P. tonganus experiences restricted gene flow between,...