Fact Of The Day:
Autumn heralds the arrival of many things: pumpkin pie, crisp morning air, and, apparently, more intelligent rodents.
Male squirrels get smarter in the fall due to their hippocampus (a part of the brain involved in memory) increasing in size during the caching season — the time of year when they gather even more nuts than usual. (In an especially adorable move, they stuff their snacks in their cheeks before moving their food to a more permanent storage spot.)
Interestingly, female squirrel brains don’t show the same effect; researchers speculate that male squirrel brains may change in the fall to act more like the females’ brains already function all year long.
The slightly bigger brains may help male squirrels remember exactly where they’ve stored their nuts, although scientists are still teasing out how.
Though we don’t tend to think of squirrels as especially bright, studies have shown that they and other tree-dwelling rodents have evolved larger brains compared to their burrowing counterparts. This all began some 34 million years ago, according to Dr. Ornella Bertrand of the University of Edinburgh’s School of GeoSciences. There weren’t nearly as many arboreal primates back then, which allowed squirrels’ ancestors to take up residence among the leaves and branches.
“When trees became available to them, squirrels’ ancestors seized the opportunity,” Bertrand explains. “This transition was a key evolutionary step for squirrels as it enabled them to acquire larger and more complex brains.”
Whether it’s more than mere coincidence that male squirrels get smarter as (human) schools come back to session remains unconfirmed.