| Institution: | 1. Department of Ecology and Evolutionary Biology and Biodiversity Institute, University of Kansas, Lawrence, KS, USA;2. Department of Biology and Museum of Southwestern Biology, University of New Mexico, Albuquerque, NM, USA;3. Division of Birds, Department of Vertebrate Zoology, National Museum of Natural History, Washington, DC, USA;4. Department of Ornithology, American Museum of Natural History, New York, NY, USA
New York Genome Center, New York, NY, USA;5. Museum of Natural Science and Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA;6. Department of Ornithology, American Museum of Natural History, New York, NY, USA |
| Abstract: | Disjunct, pantropical distributions are a common pattern among avian lineages, but disentangling multiple scenarios that can produce them requires accurate estimates of historical relationships and timescales. Here, we clarify the biogeographical history of the pantropical avian family of trogons (Trogonidae) by re-examining their phylogenetic relationships and divergence times with genome-scale data. We estimated trogon phylogeny by analysing thousands of ultraconserved element (UCE) loci from all extant trogon genera with concatenation and coalescent approaches. We then estimated a time frame for trogon diversification using MCMCTree and fossil calibrations, after which we performed ancestral area estimation using BioGeoBEARS. We recovered the first well-resolved hypothesis of relationships among trogon genera. Trogons comprise three clades, each confined to one of three biogeographical regions: Africa, Asia and the Neotropics, with the African clade sister to the others. These clades diverged rapidly during the Oligocene-Miocene transition. Our biogeographical analyses identify a Eurasian origin for stem trogons and a crown clade arising from ancestors broadly distributed across Laurasia and Africa. The pantropical ranges of trogons are relicts of a broader Afro-Laurasian distribution that was fragmented across Africa, Asia and the New World in near coincident fashion during the Oligocene-Miocene transition by global cooling and changing habitats along the Beringian land bridge and North Africa. |
