Could Global Warming Cause Animals to Shrink in Size?

Photo credit: Wikimedia Commons

From mass migrations to habitat loss, climate change is thought to be responsible for a number of significant trends in the animal kingdom.

But could shifting temperatures be responsible for the reduced size of some animals? Apparently, according to a new study, it could.SLIDESHOW: 10 Hibernating Animals Climate Change Could Wake Up

Nearly all cold-blooded organisms respond to the "temperature-size rule"—a phenomena that attempts to explain why individuals raised in warmer temperatures attain a smaller adult body size. The mechanism that causes this response, however, has never been fully understood, until now.

Andrew Hirst, a professor at Queen Mary's School of Biological and Chemical Sciences, combed through 40 years of data looking for some clue as to what process was in play. He found that growth rate (how fast an organism increases in mass and size) and development rate (how fast it passes through lifecycle stages) operate somewhat independently—and respond to temperature changes differently.

"We've shown that growth and development increase at different rates as temperatures warm," Hirst explained, "the consequences are that at warmer temperatures a species grows faster but matures even faster still, resulting in them achieving a smaller adult size."

This decoupling has other implications, too. It suggestions that fundamental rates—including mortality, reproduction and feeding—may not change together in a warming world, making it much more difficult for scientists to predict the impact climate change will have on all species.

Read more about climate change and animals:
Animals Responding 3x Faster To Climate Change Than Expected
Climate Change Forces Species to Higher Elevations

Tags: Animals | Global Climate Change


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