Welcome to the American Ornithological Society 2018 Annual Conference. We are pleased to have you join us at the lovely Hilton El Conquistador Resort in Tucson, AZ.
Avian diversification has been influenced by global climate, plate tectonic movements and bursts in specific lineages. However, these factors have not been closely examined in Passerines, the largest and most widespread avian radiation. Previous studies have been limited by many unresolved relationships among passerines or dates that are inconsistent with the fossil record. Using 4060 genome-wide loci collected from 222 individuals representing all passerine families (including an extinct family of Hawaiian honeyeaters), we estimate phylogenetic relationships among passerines using concatenation and coalescent approaches. Across analytical approaches, we recover a well-supported backbone of passerine relationships and resolve many problematic sections of passerine phylogeny, although a few sections remain difficult to disentangle even with our large dataset. We clarify the position of enigmatic taxa, such as the genera Hylia, Pholidornis, and Graueria, and recommend the recognition of at least one new avian family. Combining our improved passerine tree with divergence time estimates that were based on a comprehensive set of carefully vetted fossil calibrations yields consistent results between approaches that use both the entirety of the nucleotide alignment from all 4060 loci and random subsets of the loci. Our time-calibrated phylogeny suggests that diversification rate among passerines rose as Cenozoic global temperatures fell and that rates of passerine diversification increased significantly during the Oligocene and mid-Miocene before soaring in the Pleistocene. This study reinforces the role of global climate driving diversification in one of the largest groups of vertebrates.
