Have you ever watched a squirrel nervously dig a hole, just to drop a nut inside and then scurry off?
It’s a common behavior among squirrels and other animals to gather food when it’s plentiful,
then store it away for times when it’s not.
But I lose my keys inside my own house, and I don’t even have to put ‘em in a
hole first. Do squirrels REALLY remember where they bury all those nuts?
For a long time, people thought the only way squirrels found stored food, whether it was
left there by them or another squirrel, was thanks to their sense of smell and a healthy
does of luck. But when researchers took a closer look, they
dug up quite a surprise.
When grey squirrels were given food, they promptly buried it, because that’s just what
squirrels do. But when the squirrels went looking for it later, each of them preferentially
returned to its own food stores, even though other squirrels had buried food nearby during
the same experiment.
This means squirrels aren’t just lucky, they’ve mastered a sort of episodic memory,
the kind we use to recall events that happened at a certain place and time. They’re even
able to construct a kind of mental map of their environment, and use it to make plans
for the future.
The squirrels don’t remember the location of all their stashes, which is a good thing
for baby trees, but it’s definitely more than luck. And like any good investor, squirrels
take more time and care hiding food that’s more valuable or scarce.
The squirrels even realize that there’s thieves out there in the world, so they’ll
sometimes dig decoy holes to deceive the would-be burglars… and sometimes, it works on the
scientists too.
Western scrub jays have an even better trick up their feathery sleeve to fool potential
pilferers. When they know they’re being watched, they’ll re-bury their food as soon
as the thieves fly away.
It was once assumed that this kind of mental time travel, the ability to take actions today
for future needs, was limited to humans and higher apes, but squirrels, and even some
birds, seem to have buried THAT idea once and for all.
Stay curious