According to researchers from the universities of Florida and Nebraska, humans — and other mammals — could start shrinking if the globe starts to grow warmer. The research is based upon study of Sifrhippus fossils (a horse-like creature) found in the Bighorn Basin of Wyoming. The mammals lost 1/3 of their body weight as global temperatures rocketed up 9-18 degrees Fahrenheit in the Paleocene-Eocene period and then dropped again. As temperatures went up, the animals’ weight went down, and as temperatures cooled again, the horses’ weight rose. This phenomenon follows Bergmann’s rule, which states that relatives of the same species found in hot climates will be smaller than those in cold climates – and it could mean that as we assist the world’s changing climate with our carbon-intensive habits we could be shrinking ourselves.
“What’s surprising is that after they first appeared, they then became even smaller and then dramatically increased in size, and that exactly corresponds to the global warming event, followed by cooling,” Dr. Jonathan Bloch, curator of the Florida Museum of Natural History told The Daily Mail. “It had been known that mammals were small during that time and that it was warm, but we hadn’t understood that temperature specifically was driving the evolution of body size.” Dr. Bloch’s partner in the study, Dr. Ross Secord, from Nebraska University said, “it seems to be natural selection.”
During the period of climate change in question the horse the pair studied shrank by 1/3 in size from 12 pounds to about 8 pounds in the first 130,000 years as temperatures warmed and then grew back to its starting size as the temperature went back down during the last 45,000. Climatologists say that humans are currently escalating the pace of a global warming cycle by releasing climate changing emissions into the atmosphere – mostly due to our reliance on burning fossil fuels and our emissions-laden agricultural industry. In addition to the catastrophic weather-pattern changes, massive droughts, and species extinction generally named as consequences of our way of life, we can now add shrinking of the human race to that list.
The researchers aren’t positive that modern humans react in the same way that prehistoric horses did, but they say there’s a distinct possibility of a “honey I shrunk the human race” future.
Via The Daily Mail
Lead image by jkfid on Flickr