A dolphin walks into a bar and
makes non-coherent pulses or series of whistles. The bartender looks at the
dolphin with a dumbfounded look. One because dolphins can’t walk and two
because the bartender can’t understand dolphin—at least not yet. Scientist have
known for decades that dolphins possess a complex language or at the very least
a complex form of communication. Dolphins have the second largest brains to
body ratio second only to us (which is a measure of intelligence), they’re
self-aware, they can use tools, and can understand artificial languages.
Clearly they are intelligent, but do they have their own language?
It
turns that dolphins have a “signature whistle” that they use to identify
themselves from one another. When one dolphin greets another dolphin they use
this whistle to say who they are and then wait for their fellow dolphin to
reply with their signature whistle. The current consensus is that this
signature whistle is invented when they’re a young calf and keep it for the
rest of their lives—even more impressive they remember the unique “names” of
other dolphins for decades. Other animals have different calls for distinct
predators, such as prairie dogs, but only humans and dolphins have a name for
themselves and use these names to communicate with one another. However,
language is more complicated than just having a name. Other words are obviously
needed in order to construct sentences and convey more information.
Trying
to determine whether dolphins can formulate sentences is exactly what Ryabov
Vyacheslav is trying to elucidate in his recently published study. Two do this
he records two dolphins Yasha (male) and Yana (female) using two hydrophones (underwater
microphones) and used computer software to analyze the dolphins whistling to
each other or their alleged conversation since they took turns whistling to one
another without interrupting each other. Ryabov and his lab then looked at the
frequency of the whistles and how loud they were. From this they looked at the
peaks of clustered sound waves and assumed that if these cluster do in fact represent
dolphin speech then these clusters are phonemes (words). This is because the
clusters are spaced out over time and have different loudness as if a unique
word was being vocalized. Furthermore, looking at spectrograms (the loudness of
a sound measured over time) of dolphins and humans appear similar to each
other. However, dolphins can emit their whistles at a higher frequency than we
vocalize our words. In addition, dolphins can hear much lower and higher
frequencies than we can, as well as produce them. Since they can produce these
distinct sound clusters that appear similar to a spectrogram of our words then
that means that theoretically they have an infinite number of words and
therefore an infinite number of sentences that can be formed from these whistle
clusters by combining different clusters of different frequencies—just like the
different frequencies that we emit to make different words. Yet, for all the
work that Ryabov and his lab have done this is still not direct proof that
these clusters are in fact dolphin words.
Another biologist
by the name of Denise Herzig has been studying dolphins for three decades and
is currently trying to create her own dolphin whistles using an underwater
computer called CHAT that has a speaker that can emit whistles that were
created for her lab. The whistles that are emitted by the underwater computer
are for sargassum (seaweed) which the dolphins use to play by passing it to one
another via their fins. The lab has also created unique whistles for rope and scarf,
which are two other toys that the dolphins can use to play with. The reason for
this is that every time a dolphin goes for a toy she can play the whistle for
scarf, sargassum, or rope. She hopes that eventually the dolphins will
recognize what those whistle means and that CHAT can record the dolphins
emitting the whistles that correspond with the correct objects. In doing this
she hopes she can establish a basic language with dolphins.
The
problem is that as amazing as dolphins appear to be we are still judging
intelligence by comparing them to us. We are trying to make sense of brains and
“cultures” that evolved separately and under very drastic environments over
millions of years. Trying to compare apples and oranges is difficult enough—let
alone trying to compare dolphin speech to human speech. Trying to make sense
out nothing is a difficult task, which is made more difficult by trying to look
at a dolphin through a human perspective. Even so research continues and one
day the distant dream of finding what a dolphin says when it walks into a bar
may be a reality.
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