Inferred ancestry of individuals from the islands of Pinzón (PZN), Santiago (AGO), Santa Cruz (SCR), and Española (ESP) according to the Structure  analysis using prior population definitions. Membership coefficients are colour-coded according to islands: red (Pinzón), green (Santiago), blue (Santa Cruz), and yellow (Española). E1465 (arrow) exhibits membership coefficients of 0.501 and 0.461 for Española and Pinzón, respectively (these values do not add up to one due to nominal associations with other clusters). Structure  analysis using a model of population admixture using all available genotypic data from all populations (not just 4) yielded very similar results (data not shown).
Milinkovitch et al. BMC Ecology 2007 7:2 doi:10.1186/1472-6785-7-2