Evolutionary ecological genomics of the great tit

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Adaptation lies at the heart of Darwin's theory of evolution. For many years, biologists have tried to identify "adaptive genes" that are responsible for phenotypic changes that enable an organism to adapt to its environment. This research is important not only for understanding how Darwinian evolution comes about, but also for practical reasons. For instance, in a time of rapid environmental change, understanding the mechanisms and genetic basis of adaptation is critical to assessing the potential of wild organisms to respond to selective pressures. Studying adaptation is, however, challenging. It requires the use of rigorous mathematical models to analyse genomic DNA sequences, in order to help us understand how the genome of the organism in question evolves over time, and to identify genes showing unusual characteristics compared to the rest of the genome as a result of their involvement in recent adaptations. Thus far, this theory-based approach has mainly been applied to several well-studied organisms such as humans and fruit flies where the necessary resources are available. More recently, the rapid development of high-throughput DNA sequencing technologies has made it economical and efficient to study the genomes of wild organisms, including those studied by ecologists. In this proposal, we will use the theory-based approach to study a wild songbird, the great tit (Parus major). The great tit has been the focus of classical long-term ecological studies throughout Europe, and has been used to study key topics such as when and how the timing of breeding responds to climate change. We will use high-throughput sequencing technologies to obtain the genome sequences of multiple great tit individuals. By making use of, and further developing, state-of-the-art theoretical models, we will obtain a detailed understanding of how genetic variation is distributed across the great tit genome, and what evolutionary forces have influenced this distribution. This knowledge will enable us to search for genes that are responsible for recent adaptations, and will help us answer important questions such as whether genes affecting ecologically important traits such as the timing of breeding are involved in recent adaptations. In addition, we will examine to what extent the great tit genome differs from those of other birds such as the zebra finch, in order to understand the longer-term evolutionary history of genes of interest. These results will help us bridge the gaps in our knowledge of adaptation and genome evolution in wild great tits. More importantly, the methodology we employ is generic, and can be used to study other wild organisms. Thus, our research will be of interest to biologists working on a wide range of topics.