Department Fish Ecology and Evolution

Fish Ecology & Evolution (FishEc)

We study ecology, evolution and biodiversity of fishes and other aquatic organisms. We are interested in the mechanisms that drive the origins, the maintenance and the loss of species, genetic and functional diversity.


Read more


Failed to load

October 27, 2017

In Switzerland – not to mention the rest of Europe and the United States – freshwater fish are falling victim to a deadly disease that is rampant in the summer and dormant in the winter. It is caused by a parasite that thrives in rivers and attacks salmonid fish in particular. Researchers from EPFL, Eawag and University of Bern have come up with a mathematical model for predicting outbreaks as part of a three-year joint research program. Read more

October 3, 2017

Trout that live in stable ecosystems divide the prey spectrum among themselves and develop into specialists. In streams with instable food supply, however, the trout become generalists. Sticklebacks from different evolutionary lineages alter their environment by their feeding habits. This is deleterious to their descendants except they are hybrids. Understanding the interaction between species and environment is important for the effective protection of biodiversity.  Read more


Rebecca Best, Jaime Anaya-Rojas, Miguel Leal, Dominik Schmid, Ole Seehausen, and Blake Matthews published a paper in Nature Ecology & Evolution studying eco-evolutionary dynamics in hybridizing Swiss sticklebacks. They found that two different lineages (from Lake Geneva and Lake Constance) have different impacts on aquatic ecosystems which can then alter selection on juveniles in the next generation. This could affect the success of hybrid stickleback phenotypes in some Swiss waterbodies, as well as the future coexistence of the two original lineages.

Read the paper and a behind-the-scenes story about the study.



Joana Meier, Laurent Excoffier, Ole Seehausen and colleagues published a paper in Nature Communications. They shed light on how 700 diverse cichlid species could evolve in only 150,000 years in the Lake Victoria Region. By combining extensive taxon sampling and genomic analyses, they demonstrate that the entire “superflock” evolved from a hybrid swarm of two divergent cichlid lineages. The hybridization event facilitated the adaptive radiations by providing genetic variation that subsequently became recombined and sorted into many new species.  Read more


Research Projects

We investigate the mechanisms of speciation and adaptive radiation
Genome evolution and genomic divergence across the Swiss Alpine whitefish radiation
Investigating the interactions between migration ecology, local adaptation and diversification