Tiny fish evolved to survive colder temperatures in 3 years

University of British Columbia researchers have observed that in just three years, stickleback fish developed tolerance for water temperature 2.5 degrees Celsius lower than their ancestors.

 

This find proves that evolution may help populations survive effects of climate change.

 

"This made sense from an evolutionary perspective because their ancestors were able to adapt to freshwater lakes, which typically reach colder temperatures than the ocean," said Rowan Barrett.

 

Barrett and colleagues simulated history by transplanting marine sticklebacks to freshwater ponds and found that in as little as three generations (or three years), they were able to tolerate the same minimum temperature as freshwater sticklebacks.

 

"However, this rapid adaptation is not achieved without a cost," Barrett said.

 

"Only rare individuals that possess the ability to tolerate rapid changes in temperature survive, and the number of survivors may not be large enough to sustain the population," he added.

 

"It is crucial that knowledge of evolutionary processes is incorporated into conservation and management policy."

 

The study is published in the current issue of the Proceedings of the Royal Society B.