The role of chromosomal inversion in adaptation to heterogenous environments in seaweed flies

Species evolution and adaptation has been suggested to be enhanced by certain genomic structures. One of these are inversions, where a segment of the chromosome breaks, is reversed and then re-inserted. The most compelling aspects of inversions is reduced recombination due to a decrease in synapsis formation in heterozygotes. As a result, inversions accumulate more variation than collinear regions and show intriguing patterns, such as varying in frequency along ecological clines, being involved in hybrid vigour, and harbouring an overabundance of loci involved in adaptation, population divergence and speciation.

My project addresses the role of inversions in adaptation by means of a multi-layer integrative approach using the seaweed fly Coelopa frigida as a model species. By studying the population ecology, genomics and inversion frequencies in natural populations along a latitudinal cline, I am assessing the association between inversions and adaptation to heterogeneous environments, while accounting for demographic history. Then, using laboratory experiments, I am explicitely testing fitness and investigating functionally the genetic basis of local adaptation.

My aim is to shed light on the modalities by which chromosomic inversions contribute to adaptation in a non-model species and the selective forces and genetic mechanisms underlying the evolution of such structures.

Visit my website: http://www.normalesup.org/~cmerot/index_en.html