Bird genome 10K project, tracing the micro & macro evolutionary history of birds

Speaker: Guoijie Zhang, Ecology and Evolution, Department of Biology, UCPH

Host: Peter Brodersen, Section for Computational and RNA Biology

Abstract
Characterization of genomic biodiversity through comprehensive species sampling has the potential to change our understanding of evolution. To study evolution across a major vertebrate class, dissect the genomics of complex traits, and resolve a centuries-old debate on the avian species tree, we formed a consortium focused on sequencing and analyses 48 bird genomes covered all 30 neognath orders, representing a wide range of avian evolutionary diversity. The phylogenomic analyses with full genome data produced a highly supported avian order phylogeny that resolves many debates on the timing and topology of their radiation. Whole genome comparison for all bird species with other vertebrate species revealed several distinct macroevolution patterns of avian genome. The small genome size of bird was a consequence of massive loss of repeat elements and thousands of functional genes in bird ancestral stage. Different with other animal lineages that develop evolutionary innovation by obtaining new genetic materials, the bird genomes have extremely low new gene born rate. Instead, the bird genomes obtain millions of elements that specifically only conserved in bird lineages. These avian specific highly conserved elements are dominated by non-coding regions and have significantly high level of enhancer potential. The functional experiments well demonstrate regulatory roles of ASHCEs in the punctuated evolution of dinosaur-avian transition, and further highlight the importance of regulatory rewiring during macroevolutionary changes.