Comparative genomics of flightless and volant Palaeognathae

Repeated loss of flight in many species of birds is a dramatic example of convergent evolution, and is associated with a series of traits such as shortening of the bones in the forelimbs, extreme increases or decreases in body size, and loss of the breast bone to which the flight muscles attach. Recent phylogenetic evidence demonstrates that flight has been lost multiple times in the Palaeognathae, consisting of the paraphyletic flightless ratites (emu, ostrich, kiwis, rheas, cassowary, and the extinct moas and elephant birds), and the volant (flying) tinamous, making the ratites a prime example of convergent evolution. We sequenced and assembled ten new palaeognath genomes (including 7 ratites and 3 tinamous) to test for evidence of genomic signatures of convergence in this group. Using these new genomes, we analyzed evolutionary rates in both protein-coding genes and conserved non-coding regions to understand which, if any, regions of the genome accumulate convergent changes in flightless lineages. By studying the evolution of such traits and determining which regions of the genome likely underlie them, we can gain insight into how evolution occurs in parallel in the natural world.