As aquatic oxygen levels decrease with the changing climate, marine and lakewater species face a challenging task of adapting to hypoxic environments – or risk perishing. To examine potential for adaptation, researchers investigated two populations of threespine stickleback: one from a lake that naturally experiences seasonal long-term hypoxia and the other one that does not. They discovered that fish from the hypoxic lake used an ability to depress their metabolism to achieve a tolerance that was twice as effective as the stickleback from the non-hypoxic lake. Study authors say that, since these two communities have been isolated for about 11,000 years, this shows a potential for rapid evolution of tolerance for low-oxygen environments in this fish species.


Matthew D. Regan, Ivan S. Gill, Jeffrey G. Richards

Corresponding author:

Matthew Regan, Department of Zoology, University of British Columbia, Vancouver, BC, Email:

Original paper published in Biology Letters on November 1, 2017.