Cold-blooded animals grow bigger in the warm on land, but smaller in warm water

Compsobuthus werneri female with young (white). Credit: Wikipedia

Scientists studying arthropods, the group of cold-blooded animals that includes crabs and insects, have found that individuals within species living on land tend to grow to a larger size in the warm and nearer the equator, but that the reverse is true of species found in water.

The findings strongly support the idea that reduced oxygen availability in water causes aquatic animals to reduce their much more with warming than those on land.

The new research, which appears in Ecology Letters, gathered together existing to gain the best picture yet of how arthropod body sizes change with temperature and latitude, revealing a close match between the sensitivity of body size to temperature measured in the lab, and body size trends seen in nature.

This new information could be significant in analysing the impact of on animal species, as changes in body size with warming could affect many aspects of an animal's health, as well as alter the composition of ecologically and economically important ecosystems.

Lead author of the research, Curtis Horne, said:

"Increasing our understanding of what influences how big animals grow will mean we can start to make better predictions about how different groups of species will cope with climate change.

"We see a really close match between lab experiments and patterns observed in nature, which suggests that the same factors are at play. It brings us a significant step closer to solving a problem that has long puzzled biologists."

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Journal information: Ecology Letters

Citation: Cold-blooded animals grow bigger in the warm on land, but smaller in warm water (2015, February 15) retrieved 24 October 2019 from
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Feb 15, 2015
-The pause in global warming is now old enough to vote.

-Deniers have successfully prevented climate action for 34 years.

-Occupywallstreet now does not even mention CO2 in its list of demands because of the bank-funded and corporate run carbon trading stock markets ruled by politicians.

-Not one CO2 scientist is willing to say they are not "allowed" to say climate change is "proven" because of the "scientific method."

Feb 15, 2015
Junk science at its worst. This study does not prove a thing. All it says is animals in water are smaller because of less oxygen which does not make any sense as the largest animals on earth are whales and they live in water. if you want to confine yourself to gilled animals than how about whale sharks the largest fish which are the size of elephants. On land the animals are larger not due to oxygen. If you are larger you are less likely to get eaten just like elephants versus mice. both do very nicely, mice simply reproduce faster to make up for being eaten faster.

Feb 16, 2015

It's not wise to comment on an article when you only read the headline and ignore the story.

Maybe @mbee doesn't know what is an arthropod.

Feb 16, 2015
I was interested until GW came up. That killed the value of the article. It would be nice to have some pure science instead of everything bending to a political agenda. And a bad one at that.

Feb 16, 2015
Cold-blooded animals grow bigger in the warm on land, but smaller in warm water
If you cannot remember this rule, then you should realize, your willy is warm blooded.

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