‘Nemo' may have developed an unexpected survival tactic
According to a study published in the journal Science Advances, university researchers discovered that clownfish reduce their body size in response to marine heat waves - a behavior that significantly improves their chances of survival.
Over a five-month period, scientists recorded the length of 134 clownfish during a marine heat wave in Oceania.
Researchers said nearly three-quarters of the fish shrank in size, suggesting the presence of a widespread adaptive response.
"It was a surprise to see how rapidly clownfish can adapt to a changing environment and we witnessed how flexibly they regulated their size, as individuals and as breeding pairs, in response to heat stress as a successful technique to help them survive," Melissa Versteeg, a Ph.D. researcher at England's Newcastle University and lead author of the study, said in a statement.
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According to the study, shrinking increased a clownfish's chances of surviving extreme heat by as much as 78%.
Clownfish are not the only marine creature known to exhibit the behavior.
Researchers noted that other species, including marine iguanas, shrink under environmental stress by reabsorbing some of their bone material.
"This is not just about getting skinnier under stressful conditions," Versteeg said. "These fish are actually getting shorter."
Scientists believe this decrease in body size may result in a lower metabolism, reducing the organism's need for food.
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Dr. Theresa Rueger, a lecturer in tropical marine sciences at Newcastle University and senior author of the study, said the findings may help explain the broader global trend of shrinking fish sizes.
"Our findings show that individual fish can shrink in response to heat stress, which is further impacted by social conflict, and that shrinking can lead to improving their chances of survival. If individual shrinking were widespread and happening among different species of fish, it could provide a plausible alternative hypothesis for why the size many fish species is declining and further studies are needed in this area," Rueger stated.
The study did not indicate whether corals, a vital component of many marine ecosystems, possess similar shrinking abilities to adapt to warming oceans.Original article source: 'Nemo' may have developed an unexpected survival tactic
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