- [Narrator] These little creatures can be complicated.
They're cute, but mischievous.
It's my pizza.
They may have earned a bad rap from their antics,
but their problem solving skills inspire scientific studies.
Interactions with them are unpredictable,
and as our cities spread into their homes,
that's only increasing.
So, let's take a closer look at raccoons.
- I think I have one of the best jobs in the world.
I am endlessly fascinated by animals,
in particular, animal cognition and animal behavior.
- [Narrator] This is Dr. Sarah Benson-Amram, and she works
with some pretty great office mates.
- I find it a really fun challenge to try to put myself
into the minds of these animals and come up
with a task that I think is going to be fair
and actually get at the cognitive ability
that I'm trying to assess.
Every time we test the raccoons,
it just ends up leading to 20 more questions.
You could study them for a lifetime and never get bored
- [Narrator] Smart, adaptable
and carrying a famous resemblance around the eyes,
Native American folklore tells of a muddy brawl
with a coyote that caused the face mask,
and their know-it-all antics,
from being the reincarnation of a disobedient human.
Whether past or present, they leave an impression.
- Raccoons definitely have a reputation
for being mischievous, and they're very good
at doing things that we can find pretty frustrating
like breaking into trash cans or getting into your house.
- [Narrator] But to be fair,
(chainsaw runs)
we're kind of breaking into theirs.
- We're taking over more natural land
and more wildlife are getting pushed
into human dominated landscapes.
- [Narrator] And we're talking a lot of landscapes,
like 24 million acres
of natural space lost to urban expansion.
That's the size of nine Grand Canyons.
- [Dr. Sarah Benson-Amram] You have a lot of wildlife
that is declining
and even disappearing from some areas,
but then you also have these other wildlife species
that are able to successfully live
in cities and sometimes even use human provided resources.
- [Narrator] Which brings us back to our crafty neighbors.
- Raccoons are really adept at changing their behavior,
but they're not avoiding people as much
as they're taking advantage of a lot of the resources.
- [Narrator] Despite how hard we try to keep them away.
- We put fences, we put bungee cords on our trash cans.
So we're basically presenting urban wildlife
with increasingly difficult challenges,
and they're solving those challenges.
- [Narrator] Which raises the question,
just how smart are these animals?
- We've given them different cognitive tasks
to specifically assess this ability
of theirs to change their behavior rapidly.
- [Narrator] One test studies cognitive flexibility
with a three part puzzle.
Another looks at reversal learning by pressing buttons.
But it's a fable from a couple thousand years ago
that inspires the third.
- The Aesop's fable paradigm is taken
from the Aesop's fable, "The Crow & the Pitcher".
There's a thirsty crow and it finds a pitcher of water.
There's only a little bit of water
in that pitcher and the crow can't reach it,
so this Crow drops stones into the pitcher
which raises the water level,
now that the crow can get a drink.
- [Narrator] And in real life, birds
like rooks and crows can actually solve this problem,
as well as another animal you might recognize.
- We found some really interesting differences
between what we see with raccoons
and what they see in other studies.
Unlike the Corvids, they don't just take one stone,
drop it in, get the reward, and finish.
They actually take all the stones, dump them all in,
and just are playing with this thing constantly.
So they get the reward, but then they just keep playing
with it or they take the stones and they go hide them
in their bedding so that they can play with them later.
Once the raccoons learn this,
you can test them to see really how much they understand
about the problem.
For example, you can give them a floating ball
versus a sinking ball.
If they understand they should choose the sinking ball
because the floating ball won't actually help them
to get their reward.
They actually didn't show a preference for the sinking ball.
What they've figured out is
that they could actually make the floating ball work.
They learned to push it up
and down in the water to bounce it,
and that would spray marshmallow bits
up the side of the tube so they could get the reward.
So we're seeing
that they're really creative problem solvers.
- [Narrator] So for those skilled problem solvers,
what can we learn from their brains?
- Raccoons, who can solve a problem in multiple ways,
have more cells in their hippocampus,
and the hippocampus is thought
to be this really important brain region for cognition,
specifically memory and learning.
Interestingly it's actually
that they have more non-neuronal cells,
so things like glia.
- [Narrator] Which is helpful, considering a higher ratio
of glia to neurons could increase neuroplasticity,
which is your ability to flexibly switch your behavior.
- [Dr. Sarah Benson-Amram] Albert Einstein,
notably, had a really high glia
to neuron ratio and humans actually have a higher glia
to neuron ratio than other primates.
- [Narrator] So we're learning
that raccoon brain power plays a role
in their cognitive flexibility,
but there's another physical feature that contributes
to their craftiness.
- [Dr. Sarah Benson-Amram] Raccoons are very famous
for their dextrous forepaws.
So they have these five long fingers like primates.
- [Narrator] Just without opposable thumbs.
- Hey.
- [Dr. Sarah Benson-Amram] Instead they can use sort
of both forepaws together
to lift and then manipulate objects.
- [Narrator] And while this manipulation skill is handy.
(Audience groans)
All right.
It's not their only feature.
- Their sense of touch is incredibly sensitive.
Evolutionarily raccoons were trying to find food
in really murky water or in the dirt underneath the water.
And so they're digging around,
but they're not able to see what they're doing,
and so they're really heavily relying
on this tactile ability.
- [Narrator] Which explains another endearing trait
they've held onto.
- [Audience Member] Come on.
- People think, "Oh, when raccoons put something in water,
they're washing it,"
but actually when they put something in water,
their tactile sense is heightened
to feel things even more finely.
As urban environments start expanding
that can have a lot of really dramatic consequences
for wildlife.
Designing mitigation strategies
for human wildlife conflict will be really critical.
- [Narrator] For some cities,
ecological restoration has already shown promising results.
By boosting biodiversity, reducing city pollution.
and connecting people with nature.
- There is this effect
that when people connect to nature in their backyards
then they connect to nature even more globally.
They're more likely to be involved
in conservation efforts around the world,
and so that's something that we're really excited
about to help people to get involved
in community science projects
and to really get people excited about what's happening
in their city, in their backyard, with wildlife.