Biogeographic origins of Darwin's finches (Thraupidae: Coerebinae)

Abstract

ABSTRACT Darwin's finches are considered a classic example of an adaptive radiation, and have been the focus of numerous studies from ecological and evolutionary perspectives. Few studies, however, have attempted to investigate the biogeographic origins of Darwin's finches. In this paper, we reconstruct the ancestral biogeography of Coerebinae, the tanager subfamily that contains Darwin's finches and their 14 closest relatives. We use this reconstruction to examine the origin of Darwin's finches, and the diversification of this clade of tanagers. We test multiple biogeographic models using the R package BioGeoBEARS utilizing a recent multilocus phylogeny. We used these models to examine 2 different hypotheses regarding the biogeographic origin of Darwin's finches. The majority of ancestral ranges within this subfamily were estimated as Caribbean restricted. Biogeographic models run using 8 regions suggest Darwin's finches arose from a long-distance dispersal event from the Caribbean Islands as opposed to ...