Archipelagoes serve as important ‘natural laboratories’ which facilitate the study of island radiations and contribute to the understanding of evolutionary processes. The white-eye genus Zosterops is a classical example of a ‘great speciator’, comprising c. 100 species from across the Old World, most of them insular. We achieved an extensive geographic DNA sampling of Zosterops by using historical specimens and recently collected samples. Using over 700 genome-wide loci in conjunction with coalescent species tree methods and gene flow detection approaches, we untangled the reticulated evolutionary history of Zosterops, which comprises three main clades centered in Indo-Africa, Asia, and Australasia, respectively. Genetic introgression between species permeates the Zosteropsphylogeny, regardless of how distantly related species are. Crucially, we identified the Indonesian archipelago, and specifically Borneo, as the major centre of diversity and the only area where all three main clades overlap, attesting to the evolutionary importance of this region. 

Raw FASTQ files of target enriched samples are available on NCBI under BioProject no. PRJNA682287. Data uploaded: (1) supplementary material, (2) assembled loci, (3) gene trees, (4) abba baba output, and (5) PHRAPL output, (6) ND2 sequences. Please refer to README for more details.