A new Science Advances study linking the shrinking of mammals and global warming as Earth’s carbon dioxide levels rise has researchers keeping a close eye on the issue.
The study, published Wednesday, March 15, reports global warming has reduced the size of mammals, not humans, in the ancient past. University of New Hampshire researcher and author of the study, Abigail D’Ambrosia, told the Associated Press that certain animals have shrunk in the past on at least two occasions in Earth’s history.
“It’s something we need to keep an eye out for,” D’Ambrosia told A.P. “The question is how fast are we going to see these changes.”
The Science Advances study concerned fossils uncovered in the Bighorn Basin of Wyoming, according to the report.
Three animals are highlighted in the study and A.P. report as having noticeably gotten smaller as Earth warmed. About 54 million years ago, an early horse decreased in size by 14 percent from 17 pounds to 14.6 pounds.
The lead researcher told A.P. that “these guys were probably about the size of maybe a dog” and “they may have gone down to the size of a cat.” Another creature studied was the Cantius abditus — lemur-like animal, — which shrunk by 4 percent.
“However, irrespective of the exact mechanism, it is clear that body size dwarfing in some mammal lineages is closely linked with hyperthermals and may be a common evolutionary response,” the report reads. “This suggests that dwarfing will be a likely natural response of some mammals to future global warming.”
To put it in layman’s terms, the study links shrinking animals to the Earth warming.
Princeton climate scientist Michael Oppenheimer tells A.P. that 56 million years ago, the planet saw temperatures rise 9 degrees. He said this “natural warming” most likely stemmed from methane emitting from dead plants and animals on the sea floor.
“These results are very significant because they provide another independent test of whether climate drives changes in body size in mammals,” Jonathan Bloch, curator of vertebrate paleontology at the Florida Museum of Natural History, told A.P. “If we start to see patterns repeat themselves, we can learn from that. And what we learn from these lessons will certainly be important as we think about the possible response of plants and animals to future climate change.”
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Global warming study has scientists concerned about shrinking mammals – MLive.com