A new research suggests that increased temperature on earth causes shrinkage of some mammals. Their tendency of becoming smaller is directly related to the hot temperature of the earth.
The conclusion was based on the new evaluation of teeth and jaw fragment fossils collected from the Bighorn Basin. According to Los Angeles Times, the study was conducted by Abigail D'Ambrosia, a graduate student at the University of Hampshire. In adult mammals, the best representation of their size is the teeth as stated by D'Ambrosia.
The researchers were able to compare the tooth size of the same species overtime, and it was proven that shrinkage in mammals occurred approximately from 56 million years ago. A specific example for this is "Sifrhippus" which shrank by at least 30 percent from the first 130,000 years of earth's increasing temperature. When the planet's temperature returned to usual, its body size slowly went back to normal.
As reported by Scientific American, it takes a longer rate at which heat moves out of the earth. This process is called convective transport wherein the transfer of heat comes within the core, mantle and lastly, to earth's surface. However, in the real sense, climate change is still a big contributory factor in global warming affecting mammals.
D'Ambrosia wanted to know if shrinkage on mammals has occurred even with the smaller warmer scenario on earth 54 million years ago. She and her team have gathered and measured the four earthling's teeth that lived before and during the event.
From the evaluation, of the four teeth from the mammals, the difference in their sizes before and after the warming event was obvious. These findings suggest that the shrinkage response scales directly and proportionately related to the degree of warming.
However, D'Ambrosia stated that there might be other reasons for the shrinkage of these mammals such as dehydration and food craving. The situation is also related to surface-area-to-volume ratio wherein smaller animals' releases heat easily while the bigger ones are able to retain heat in cold habitats.