Phylogenomics and the Avian Tree of Life

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The accelerating loss of biodiversity on the planet and the need for the conservation depends on having a stable classification of living organisms based on their evolutionary relationships. Although birds are conspicuous components of ecosystems and are valued aesthetically and economically, the base of the avian tree of life remains unresolved. The major cause of this problem is that some time after the K/Pg extinction event 65million years ago (Mya) the major groups underwent rapid radiations that make it extremely difficult to reconstruct their branching order, and how they are related by shared common ancestry. My research group plans to use retroposon markers and cost-effective next generation sequencing to rapidly assemble sequences of 100 genes for 135 species in all 27 orders of birds to resolve the branching order of bird orders. This cutting edge research program will also allow us to test the following major hypotheses in evolutionary biology: did many lineages of crown-group birds originate in the Cretaceous or radiated after the K-Pg extinction event? Is the distribution of modern birds due to continental drift or dispersal well after continental fragmentation? Are the amazing morphological changes in the large flightless ratite birds caused by relaxation of selective constraints that operate in flying birds? Is variation in morphological phenotypes associated with mutations in protein-coding genes or proliferation of regulatory elements in genomes? Is variation in rates of evolution in different groups of birds associated with variation in generation time, metabolic rate or body size? By mapping characters on a highly resolved bird phylogeny and using comparative methods we can discriminate among these alternatives, and significantly advance knowledge of the evolutionary biology of birds. This programme will provide training in genomic applications to ecology and evolutionary biology for highly qualified personnel that can work in Universities or applied genome centres or biotechnology businesses. This research has applications in breeding programmes of birds and in conservation.