Phylogeography of bulbuls in the genus Iole (Aves: Pycnonotidae)

摘要

Southeast Asia is one of the most geologically dynamic regions of the world with great species diversity and high endemism. We studied the bulbuls of the south and southeast Asian genus Iole (Aves: Pycnonotidae) in order to analyse their evolutionary relationships and describe their patterns of diversification and delimit species boundaries. Our phylogeographic reconstruction, based on two mitochondrial and one nuclear markers, sampled from all 13 recognized Iole taxa, presently grouped as four species, revealing three primary lineages: (1) a Palawan lineage (2) a Sundaic group distributed in the Malay Peninsula, Sumatra and Borneo and (3) an Indochinese group distributed throughout continental Southeast Asia. Divergence time estimation suggested that the Palawan lineage diverged during the Miocene (around 9.7 Mya), a later split between the Sundaic and Indochinese lineages occurring around 7.2 Mya. The present classification of Iole based on morphology does not accurately reflect taxonomic relationships within the genus, in which we recognize five more putative species. An integrative approach that incorporates morphology and bioacoustics should further refine our understanding of species limits among Iole taxa.