Scientists have revealed that there is evidence to show that global warming could shrink certain mammals.
Warm-blooded animals have reportedly shrunk at least two times over the course of Earth's history -- at times when carbon dioxide levels and temperatures rose. Abigail D'Ambrosia, a researcher with the University of New Hampshire, said she feared that some mammals could shrink at even faster rates than in the past due to the increasing threat of climate change.
"It's something we need to keep an eye out for," she told CBS News. "The question is how fast are we going to see these changes."
Around 54 million years ago, three species reportedly shrank a noticeable amount due to a sudden increase in the planet's temperature. An analysis of fossil teeth revealed the shrinkage of the three species -- one of which was an early horse that shrunk 14 percent.
"These guys were probably about the size of maybe a dog, then they dwarfed," D'Ambrosia said. "They may have gone down to the size of a cat."
Heating and shrinking, research showed, was connected over millions of years. Scientists say that the last warming period lasted for 170,000 years, reports the Los Angeles Times.
"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 with the Florida Museum of Natural History, said. "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."
Bloch added that he feels as though these changes are something to expect in relation to climate change in the coming years.
"Based on what we now understand about these repeated past experiments, it is becoming increasingly clear that one of the changes that we should expect to see with future global warming will be shifts in body size for some mammal lineages," he told the Los Angeles Times.
Though the idea of animals shrinking because of a warming climate might be shocking to some, most scientists are aware that mammals get smaller in warmer climates -- something known as Bergmann's rule.
"The idea behind it is that it is more efficient to cool off if you have a small body size because you have a larger surface-area-to-volume ratio," D'Ambrosia told the Los Angeles Times.