The changing climate in the present situation may make us shorter over time, a new research suggest that found that mammals in the past coped with rising global temperatures by shrinking in size. Dwarfism was previously seen in mammals, and in fact, it is still there now. Mostly, mass dwarfism was linked to extreme warming events. The study was published in the journal Science Advances.
Dwarfism amongst mammals were seen previously in cases where there was extreme temperature increase, but with the current climate trends, the research suggests that the it can also happen in case of smaller events. The findings could also help us understand the impact of man-made climate change.
“We know that during the largest of these hyperthermals, known as the Paleocene-Eocene Thermal Maximum, or PETM, temperatures rose an estimated 9 to 14 degrees Fahrenheit and some mammals shrank by 30 per cent over time, so we wanted to see if this pattern repeated during other warming events, the hope is that it would help us learn more about the possible effects of today’s global warming,” said the lead author of the study Abigail D’Ambrosia, a PhD student at New Hampshire University.
The Teeth Determines Body Size
The molar teeth are a proxy for the body size. The researchers collected teeth and jaw pieces in the Bighorn Basin region of Wyoming in the US. They focused mainly on the early mammals. These included the Arenahippus, an early horse which was of the size of a small dog, and Diacodexis, a predecessor to hoofed mammals which was as small as a rabbit.
During the hyperthermal period, these mammals significantly had reduced body sizes. Arenahippus was found to be decreased by about 14 per cent in size, and the Diacodexis was found to be decreased by about 15 per cent. A smaller body would cool down faster and need lesser nutrients.