The study demonstrates that eutrophication levels not only account for the loss of species but are also responsible for the loss of differentiation among the surviving species.

Evolutionary biologist Ole Seehausen, the lead author of the study, comments "Speciation reversal appears to be more widespread than has previously been supposed; this process involves the rapid disappearance of species which evolved over thousands of years by adaptation to specific ecological conditions.

"This means that the protection of biodiversity requires not only the conservation of existing species, but the protection of ecological and evolutionary processes which assure the maintenance of specialists and promote the generation of new species.

Lake eutrophication causes loss of fish species