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.


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November 18, 2020

Four Eawag researchers among the most-cited scientists

Researchers Juliane Hollender, Ole Seehausen, Bernhard Truffer and Urs von Gunten from the aquatic research institute Eawag are among the "highly cited researchers 2020". Read more

November 12, 2020

Two lakes, seven whitefish species

In the journal ZooKeys, a group of scientists from Eawag and Bern University have described seven whitefish species endemic to the Bernese Oberland lakes – including four not previously described scientifically, two of which have only been identified as distinct species in the last few years. In Switzerland, the whitefish diversity of Lakes Thun and Brienz is possibly matched only by that found in Lake Lucerne; and in deep lakes of this kind further surprises cannot be ruled out. Read more


The superfast radiations of Lake Victoria and Lake Malawi are marked in green. The photos give an impression of the morphological diversity of the cichlids. (Graphic: Matthew McGee et a., Nature 2020)

August 26, 2020

Explosive diversification explained by network analysis

Using genomic analyses of 100 cichlid species, scientists from Eawag and the University Bern, together with co-workers in Australia, the UK, Tanzania, Uganda and the US, have investigated the striking variation observed in cichlid fish speciation rates. Their findings show that exchanges of genetic variants between existing species dramatically accelerate the development of new species – given favourable ecological conditions. Read more

Original publication

Latest Publication

Selz, O. M.; Dönz, C. J.; Vonlanthen, P.; Seehausen, O. (2020) A taxonomic revision of the whitefish of lakes Brienz and Thun, Switzerland, with descriptions of four new species (Teleostei, Coregonidae), ZooKeys, 989, 79-162, doi:10.3897/zookeys.989.32822, Institutional Repository

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