Dr. Con Slobodchikoff's extensive research demonstrates that prairie dogs possess a sophisticated communication system, capable of identifying specific predator species, describing their individual characteristics, and even creating novel terms for unfamiliar objects, challenging the long-held belief that complex language is uniquely human.
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This is Dr. Con Slobodchikoff.
For over 30 years he has studied
communication in prairie dogs and his
work represents some of the most
sophisticated research we have to date
about animal communication.
His findings show that prairie dogs can
not only use words to identify specific
species of predators, but are even able
to provide detailed descriptions of
individual predators such as their color
and size.
This may not sound like much at first,
but for a long time scientists believed
that animal calls are simply emotional
reactions to the world around them.
The ability to have specific or
meaningful communication has often been
considered to be uniquely human.
Yet through decades of experiments he
has found that prairie dogs are able to
use adjectives and even create new words
for things they had never seen before.
Now, this certainly sounds very
exciting, but at this point you're
probably wondering how does he actually
prove this?
Well, let's take a step back and look at
>> At a young age Con learned a very
important lesson that would come to
shape his entire career.
Having grown up speaking Russian, when
he first moved to the United States his
teachers didn't realize that some
children simply didn't grow up speaking English.
English.
Instead they assumed something was wrong
when he spoke slowly and sent him to a
psychologist where he was quickly
diagnosed with a speech disability.
This experience taught him something
important very early in life that even
experts can be wrong when they rely too
heavily on their assumptions.
Years later that lesson would quietly
shape the way he came to look at animals.
animals.
Because outside of school Con found he
developed a love for the animals around him.
him. >> [clears throat]
>> [clears throat]
>> As a teenager he joined an academy where
he went on numerous field trips to
different habitats across California.
For the first time he was able to spend
hours watching animals in the wild to
observe their behavior and their interactions.
interactions.
And this fascinated him because all his
life he had been told that animals were
simple creatures and weren't capable of
complex thoughts.
Yet what he saw in the field was vastly different.
different.
And as he reflected on his own
experience in school, he wondered if we
might be making a similar mistake when
we think about animals.
So after receiving his PhD, Con set out
to study the social behavior of prairie dogs.
dogs.
But little did he know this would soon
lead him down a very different path.
So next, let's take a look together at
>> When he first started his research, Con
had often noticed that prairie dogs gave
alarm calls whenever predators were nearby.
nearby.
At the time, like most researchers, he
assumed that these calls were fairly
simple and was just a general signal
that something dangerous was close.
But one day he came across a paper which
found that ground squirrels in
California used different alarm calls
for aerial and ground predators.
He thought this was pretty interesting
and wondered if it could apply to
prairie dogs as well.
So the next time he was in the fields,
he started paying closer attention.
And sure enough, whenever a hawk
appeared, the prairie dogs made this sound.
A short single note bark. But when there
were dogs, coyotes and other ground
predators nearby, they instead made this
Which was a slightly different sound,
but repeated rapidly.
Now he thought this was really interesting.
interesting.
Over the next few weeks Con found
himself spending longer and longer in
the field taking notes on everything
that he saw.
And as his ears became more and more
tuned to the sounds they made, he
started to notice something very strange.
strange.
It seemed like the sound they made for
different ground predators had very
slight variations to them.
But more than that, it seemed to always
vary in the exact same way depending on
the type of predator.
And slowly an idea began to take shape
in his mind. So then I had an insight.
What if the prairie dogs are
talking about the species of predator?
Now mind you,
nobody believed this
at the time.
But I thought, what if? >> [snorts]
>> [snorts]
>> So he decided to try and test this. He
would first observe how they would react
when there were different predators nearby.
nearby.
He noticed that when coyotes were
nearby, the prairie dogs would make this sound.
And they would also run to their burrows
and stand alert.
For domestic dogs, they instead made
But rather than run to their burrows,
they would simply stand alert wherever
they were at the time. And it's
important to note that they would never
make a mistake even when certain
domestic dogs looked very similar to coyotes.
coyotes.
And finally, for humans, they made this sound.
And they would respond by not only
running to their burrows, but would
quickly dive inside.
He believed the different responses was
likely due to how dangerous they
perceived each predator to be.
Next, he would record the calls made
against each predator and replay the
recorded sounds to different colonies of
prairie dogs.
If they really were communicating
something beyond just ground predator,
then they should react appropriately to
each call.
And when he did, that's exactly what happened.
Over hundreds of trials, the prairie
dogs always responded in the appropriate way.
way.
And with this he had shown that prairie
dogs weren't just making simple alarm
calls, but there was specific
information being transmitted in these calls.
calls.
When I started working with prairie
dogs, I started exploring this issue and
eventually found
that in the alarm calls of prairie dogs,
they have different alarm calls for
different species. They have an alarm
call for a human, they have an alarm
call for a coyote, another one for a
dog, another one for a hawk. We found
some other alarm calls for other animals
as well.
But this begs the question, how do we
know that they are actually referring to
the species rather than just telling
each other to run or hide in a certain way?
way?
To answer that, we'll look at a very
interesting piece of evidence in the
>> As Con continued his research, he began
building a much larger library of alarm
calls from different predator
encounters. But one thing kept bothering him.
him.
To human ears, many of these calls
sounded incredibly similar, yet the
prairie dogs never seemed confused and
always seemed to know exactly what kind
of predator was nearby.
So he began looking more closely at the
calls themselves using spectrograms to
compare their structure and sorted them
by predator type.
And then he noticed something very interesting.
interesting.
While calls for the same predator seemed
to follow a certain pattern in their
frequency and structure, there was still
a lot of variation between the
individual calls themselves. Much more
than you'd expect based on natural
differences in individual prairie dogs.
But that raised the bigger question. If
the overall pattern already told them
the predator category, then why was
there still so much variation between
the individual calls?
And one day as he was staring out into
the prairie, a thought began to surface
in his mind.
So again I had an insight. What if they
are describing the individual features
of predators?
Now this is really way out
at the time.
Nobody, but nobody believed that.
Nobody, but nobody hardly believes that
at all today.
So he designed an experiment to try and
test this.
He first had one of his students walk
through the prairie field on one of
three randomized paths wearing a blue
shirt and recorded the calls they made.
And then they repeated this with a green
and yellow shirt.
He would repeat this many times before
analyzing each of the calls.
And what he noticed was that while all
the calls were consistent with the
pattern of human calls, they were
different each time.
But it wasn't that simple because while
the blue shirt calls were distinctly
different to the others, this wasn't the
case between the yellow and green shirt
calls, which were much more similar.
Now this is really interesting because
prairie dogs have dichromatic color
vision, meaning while they can easily
distinguish between blue and yellow
wavelengths, they have a much harder
time doing so for green and yellow,
which are much closer to one another.
This suggests that prairie dogs are in
fact actively changing what they're
saying based on the individual
appearance of specific predators.
The other really interesting thing he
noticed was that the prairie dogs still
responded the same way to the different
colored calls by running to the burrows
and diving inside.
And Con believed that this provided more
evidence that they weren't just telling
each other how to run and hide, but
rather actively encoding information on
the predators themselves.
He would later do this for different
factors like size, speed of approach and
shape. And in one experiment, he even
tested whether prairie dogs would have a
distinct reaction to someone holding a gun.
gun.
We had a person walk out in a blue shirt
who was carrying a shotgun and initially
he fired the shotgun off into the air.
And [music]
the prairie dogs gave an alarm call for
him that indicated that he had a blue
shirt and described his physical
features, but they also had an addendum,
[music] which we thought indicated that
he had a gun. And then for the length of
the experiment, another month, whenever
he showed up,
he was >> [music]
>> [music]
>> always dressed the same way, so they
gave the call for him describing that he
had a blue shirt, but they also tacked
on this addendum, which we thought
carried the meaning of a gun. So for a
month, they remembered
From his observations, Cohn suspects the
reason why they need to encode so much
information into their calls is because
it allows them to respond appropriately
to individual predators, particularly
ones that they know that have been very
dangerous in the past.
For example, if a coyote has a
particular hunting style, like lying
next to a burrow and waiting for prairie
dogs to come out, thinking they're safe,
then knowing when that coyote is around
can help them survive this.
Now, this is pretty amazing, right? And
when Cohn first realized this, he was
extremely excited. And he couldn't help
but wonder what words the prairie dogs
used to describe him.
But despite this, there was one question
left in Cohn's mind.
All his life he had been told that
animals lack the capacity to create
meaning or have novel thoughts. So how
would they respond if they came across
In the months that followed, this
question kept coming up in Cohn's mind.
And the more he spoke to colleagues
about it, the more impossible it seemed.
Different calls and descriptions for
predators was one thing, but being able
to come up with new words is a different
claim entirely.
And yet, if their language really was as
complex as Cohn thought it to be, then
at some point, they would eventually
come across things they hadn't seen previously.
previously.
And so, in spite of all the pushback
from his colleagues, he decided to push on.
on.
For this experiment, he needed prairie
dogs something they had never seen
before, something alien in nature.
And for that, he chose a triangle.
Or more specifically, the silhouette of
a triangle, because there was no way the
prairie dogs would have ever seen a
triangle approaching them in nature.
So what he did was he first built
observation towers within the colony and
set up a pulley system between the towers.
towers.
He would then attach wires to a large
cardboard cutout of a triangle.
Then they would essentially have the
triangle run across the field while
observing how the prairie dogs responded.
responded.
They also later did this with cutouts of
an oval and a rectangle.
And it's quite interesting to think
about what the prairie dogs were
thinking in those moments.
But what they found was that the prairie
dogs would make a call that was unlike
anything they had heard before.
It was distinct in its overall acoustic
structure, yet surprisingly consistent
amongst all prairie dogs that saw the
moving shape.
This suggests that these calls were not
just made from confusion or surprise
from one single individual.
Instead, it seems their communication is
flexible enough to extend to something
entirely new.
We had circles and we had triangles
running across the field on a set of
wires, and the prairie dogs had distinct
calls for the circles and they had
distinct calls [music] for the
triangles. So these are things that
prairie dogs have never seen before, and
yet they were able to come up with a
novel word >> [music]
>> [music]
>> for each one of those things, for an
>> Cohn has often wondered why we are so
quick to assume that language is
something only humans [music] are
capable of.
After all, if we already accept that we
share so much with other animals, like
our biology, our DNA, even our immune
systems, then [music] why not
communication, too? Especially when such
a thing would offer such a clear
survival advantage.
There's no doubt that our language is
likely more complex than most others out
there, but to Cohn, language is less
something animals either have or don't,
and more something that may instead
exist on a spectrum.
And what I found especially moving was
that even after all these years, he
never seemed interested in proving that
point through cruelty.
Some critics argue that to really test
these ideas, prairie dogs [music] should
be raised in captivity, isolated, or
subjected to more invasive experiments.
But Cohn never agreed with that
approach, because for him, [music] these
were never just experimental subjects.
They were living animals.
Even late in his career, what stood out
to me was how much his work was driven
not just by scientific [music]
curiosity, but by genuine care.
He spoke about the countless animals
that are put down each year for
so-called bad behavior, and wondered how
much of that suffering might come from
[music] a much simpler problem.
That we still simply don't understand
what they're trying to say.
He hopes for a future where our research
will one day allow us to build tools
[music] that could help us translate
animal signals in real time, and really
narrow the gap between [music] their
world and ours.
Even after retiring from academia, Cohn
never really stopped his work.
He spent years continuing to speak
publicly [music] about animal
communication through books and
interviews to try and convince the world
that animals may be saying far more
[music] than we give them credit for.
He even wrote a book called Chasing
Doctor Doolittle, in which he details
his life's work and the [music] long
struggle to get others to take animal
communication seriously.
Because if there was one thing that Cohn
has found after all these years, the
real challenge was perhaps never about
getting animals to speak, but rather
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