Before you worry too much about putting on those holiday pounds, consider this: We're not the only species with weight issues.
- Mammals that live near or with humans, from lab rats to pet pooches, have gotten fatter over recent decades.
- Fatter lab animals are the hardest to explain, since their diet is tightly controlled and well documented.
- Endocrine disruptors, pathogens or temperature changes might play a role and could also factor into human obesity.
There's no question that humans have been getting bigger and bigger, and now it seems that animals living near us are coming along for the ride. A new study of 12 distinct populations of eight different mammals -- including feral rats, lab animals and domestic pets -- shows that they, too, have been gaining weight over the last several decades.
"It could be that for every one of these populations, there's a different reason why their weights are going up," said study lead author David Allison of the University of Alabama at Birmingham, who published the findings today in the Proceedings of the Royal Society B. "It could also be that within each, there are different reasons. What's exciting to speculate about is, could there be some factor that is affecting all of these?"