The complexity of mutualistic interactions have attracted a great deal of scientific attention, and although general evolutionary expectations exist, no unifying evolutionary theory of mutualism has been established. Largely impeding the development of a synthetic framework for mutualism are misunderstandings, or incomplete understandings, of individual case studies. No mutualism is perhaps more representative of this than the iconic clownfish-sea anemone symbioses, a model mutualism regularly used for exploring fundamental biological processes, but one in which our understanding remains wildly incomplete due to a lack of research into the evolution and genomics of the host anemones. The goals of this project are to conduct full genome sequencing of the clownfish-hosting sea anemones to test general evolutionary expectations of mutualism. Specifically, I will test:
1) Whether the mutualistic benefits of hosting clownfishes has led to multiple adaptive radiations in host sea anemones
2) Whether the mutualistic benefits of hosting clownfishes led to significant ecological opportunity for host anemones, and thus, signatures of demographic population expansion, that coincide with the onset of the symbiosis.
3) Whether mutualism with clownfishes has generated similar selective pressure and convergent genome evolution and architecture among host anemones.
4) The Red King Hypothesis, which states that the balance of mutually exploitative symbioses should lead constituent mutualistic lineages to have slower rates of molecular evolution than their free-living relatives.
This project will be the first genomic investigation into the mutualism of the clownfish-hosting sea anemones, provide novel insight into this charismatic symbiosis that will bear on the interpretation of dozens of prior studies that span scientific disciplines, and generate valuable community resources for future research. The proposed research is timely and necessary as the recently published genomes of 10 clownfish species have already led to a number of publications on the genomic evolution of clownfishes. Generating genomic data for the clownfish-hosting anemones is critical to provide proper perspective on how the entire symbiosis has evolved and place future papers into a proper mutualistic context. Further, much of the general expectations of how biodiversity evolves within mutualisms come from terrestrial examples. Adding thoroughly disentangled marine examples is thus critical for providing comparative data in order to evaluate the generalities of mutualism across ecosystems.
