Alan LE MOAN

I am a population geneticist interested in a broad range of questions in evolutionary biology, structured around three main research themes: speciation in intertidal environments, marine invasions, and urban evolution, as well as the connections between these fields. My work combines field-based observations and experiments with -omics sequencing approaches to investigate evolutionary processes.

Speciation in the intertidal zone: Understanding how gene flow is reduced and ultimately halted between species is a central goal of speciation research. I use the intertidal zone as a natural laboratory to investigate the evolutionary processes underlying speciation. My research focuses on local adaptation, the role of gene flow along the speciation continuum, the consequences of chromosomal rearrangements on the evolution of reproductive barriers, and the interplay between sex chromosome evolution and reproductive isolation. My current research primarily focuses on marine gastropods and brown algae. I am notably working hybrid zones between species exhibiting distinct reproductive strategies. Through these systems, I aim to understand both how reproductive traits evolve and how differences in these traits contribute to the formation and maintenance of reproductive barriers.

(photo credit: Wilfried Thomas)

Marine invasions: I am also interested in marine biological invasions. Marine invasive species encompass a wide range of invasion histories, providing excellent opportunities to study the evolutionary consequences of these extreme demographic events on genetic diversity. Using population genomic approaches, I investigate how invasion events affect genetic diversity and genomic indicators of fitness, such as genetic load, and how these genetic outcomes of introductions, in turn, influence invasion dynamics. I am currently developing projects on these questions using Sargassum muticum and Undaria pinnatifida as model systems.

Urban evolution along the seashore: Marine coastal habitats are profoundly impacted by human activities. Jetties and breakwaters alter wave exposure regimes along the shoreline, while harbours concentrate pollutants derived from human waste. Maritime transport and aquaculture practices also directly affect the dispersal and migration patterns of organisms, thereby influencing gene flow between distant populations. In my research, I investigate how multiple features associated with human activity and urban coastal development shape the evolutionary trajectories of species.