How to speak monkey: The language of cotton-top tamarins - Anne Savage
Living with her family high
above the ground
in the northern tropical forests
of Colombia,
you will find Shakira,
a cotton-top tamarin with a penchant
for conversation.
Say, "Hola!"
Though you may not realize it,
this one pound monkey communicates
in a highly sophisticated language
of 38 distinct calls
based on variations of chirps
and whistles.
The response she just gave is
known as a "B chirp",
a call often directed at humans.
To appreciate the complexities
of Shakira’s language,
let's learn a few chirps and whistles,
then examine how their combinations
form grammatically structured sequences.
The chirp Shakira used to greet us
comes from a class of calls known as
single frequency modulated syllables.
This class is made up of short
duration calls, or chirps,
and long duration calls,
like screams
and squeals.
Researchers have determined that there
are eight different types of chirps
categorized by stem upsweep, duration,
peak frequency, and frequency change.
In addition, each chirp has
its own unique meaning.
For example, Shakira’s “C chirp”
is used when she is approaching food,
where as her “D chirp”
is only used when she has
the food in hand.
Single whistles also exhibit
a unique intention with each call
and just as there are
eight different chirps,
there are five different whistles.
Based on frequency modulation,
single whistles are subdivided
into four categories:
squeaks, initially modulated whistles,
terminally modulated whistles,
and flat whistles.
The language's quality of unique intention
is wonderfully exemplified by the category
of initially modulated whistles.
These whistles change based
on the proximity
of Shakira to other members of her family.
If Shakira is greater than 0.6 meters
from her family,
she’ll sound a large
initally modulated whistle.
But if she’s less than 0.6 meters
from her family,
she’ll sound a small
initially modulated whistle.
Now that we’ve learned a few
chirps and whistles,
Shakira wants to show off by taking you
through a quick day in her life
with these calls.
While heading towards a feeding tree
for her first meal of the day,
she says: “(monkey noise)“,
a call most often used
in relaxed investigations.
However, suddenly she spots
the shadow of a hawk.
"E chirp" for alarm.
This call alerts her family
to the presence of this predator,
and Shakira jumps to the safety
of an inner branch.
The coast seems clear,
so Shakira makes her way towards her dad.
Wait, wait. Who is that?
Ah, it's her younger brother, Carlos.
Cotton-top tamarins often squeal
during play wrestling.
Uh-oh. He’s playing a little too roughly,
and Shakira screams,
alerting her parents to help her.
Her dad makes his way
towards the ball of rolling fur
and her brother stops.
Shakira shakes herself
and scratches herself to get the hair
on her head back in place.
Then Shakira spots another group
of unfamiliar tamarins
and hears their normal long call.
She turns to her family.
Did you catch that? First there was a chirp, and then a whistle. This is what’s known as a combination vocalization, a phrase that contains both a chirp and a whistle. These are two calls strung together to convey a message. The combination of these two elements alerts her family to the presence of another group, the “F chirp”, and the distance they are away, the normal long call whistle. In other words, Shakira just said a sentence. Her simple demonstration is just the tip of the iceberg. She’s got trills, chatters, multiple whistle calls, more combination vocalizations, even twitters. Yet sadly enough, we may not get to hear everything she has to say. Mixed in with chirping sonatas from high above is the constant thud of a machete chopping trees. Shakira’s habitat in Colombia is being cut down, piece by piece, and if we don't work to protect the critically endangered cotton-top tamarin, it will become extinct in our lifetime. If the chirp from one tamarin to the next has proven to be more than just idle chit chat, imagine what else we have left to discover. Imagine what else Shakira can tell us.
Did you catch that? First there was a chirp, and then a whistle. This is what’s known as a combination vocalization, a phrase that contains both a chirp and a whistle. These are two calls strung together to convey a message. The combination of these two elements alerts her family to the presence of another group, the “F chirp”, and the distance they are away, the normal long call whistle. In other words, Shakira just said a sentence. Her simple demonstration is just the tip of the iceberg. She’s got trills, chatters, multiple whistle calls, more combination vocalizations, even twitters. Yet sadly enough, we may not get to hear everything she has to say. Mixed in with chirping sonatas from high above is the constant thud of a machete chopping trees. Shakira’s habitat in Colombia is being cut down, piece by piece, and if we don't work to protect the critically endangered cotton-top tamarin, it will become extinct in our lifetime. If the chirp from one tamarin to the next has proven to be more than just idle chit chat, imagine what else we have left to discover. Imagine what else Shakira can tell us.
