Reef fish have genetic tool to adjust to warmer ocean conditions: study

SYDNEY, May 1 (Xinhua) -- An international study led by Australian researchers has found that the offspring of reef fish that live in warmer parts of the ocean will be better suited to climate change.

The study, published on Tuesday, was led by the Centre of Excellence for Coral Reef Studies, and was the first ever to uncover the possible link between transgenerational acclimation and climate change in a vertebrate.

"When parents are exposed to an increase in water temperature, we found that their offspring improved their performance in these otherwise stressful conditions by selectively modifying their epigenome (DNA methylation)," author of the study Professor Philip Munday of the Coral CoE at James Cook University explained.

Researchers put two generations of Acanthochromis polyacanthus (damselfish) in waters of three different temperature ranges up to 3 degrees Celsius higher than the current ocean temperature in order to mimic their performance in future environments.

The results showed the offspring performed better than their parents did by having different gene expressions that enabled them to maximize their utilization of oxygen and energy -- a mechanism called "acclimation".

"Acclimation may buffer populations against the impacts of rapid environmental change and provide time for genetic adaptation to catch up over the longer term," Munday said.

The researchers believe exposure to a higher water temperature caused by global warming may lead to genome-wide changes in DNA methylation, which could play a critical role in the mechanism of acclimation of the offspring and help the species survive in tougher ocean environments. Enditem