Animal language vs. human language

Language is an extremly important aspects of our human lives, and its aquisition might be an innate part of our brain that separates us from animals. However, different animals can understand language on different levels, as noted by Steven Pinker in his book The Language Instinct:

The most receptive trainee for an artificial language with a syntax and semantics has been a parrot; the species with the best claim to recursive structure in its signaling has been the starling; the best vocal imitators are birds and dolphins; and when it comes to reading human intentions, chimps are bested by man’s best friend, Canis familiaris. [1]

Since animals can understand humans on some level we must ask ourselves: How similar is animal language to human language? It seems the answer may be pretty similar, since a recent article in PLOS Biology has shown that, at the fundamental level, the vocalizations of the chestnut-crowned babbler can emulate some complex aspects of human language. [2]

So what?

Sabrina and colleagues took these babbler birds and analyzed how they talk. They found that the birds communicate using different combinations of a small number of meaningless sounds. This ability is known as generative power which can allow limitless thoughts and ideas to be transmitted because their are many meaningless sounds and they can be combined in many, many ways. For example, the word “cat” has three sounds, /k/, /æ/ and /t/ which can also be rearranged to form the words “act”, “tack” or “at”. Previously researchers had found that some animals had generative power, but there was never any strong evidence that the rearrangements had a qualitative change in the contextual meaning.

The researchers came to this conclusion from using a clever experiment. The researchers found that birds had two types of sounds that they would mix together to make to get different words. When they played back the original sounds to the birds, the birds carried out the typical behavior. However, if certain sounds in the song were replaced by another sound the birds wouldn’t carry out the same behavior. That is, instead of saying “cat” to the birds, the researchers said “cot” and noticed the birds didn’t behave the same as if they said “cat”. This is an important distinction because it means that bird words are composed of several meaningless sounds in an important order and that these meaningless sounds could be rearranged for different words!

Who cares?

Biologists and philosophers should care about this one, because it tells us that the ability to generate words from meaningless sounds has evolved early on in lifeforms.

Now what?

It would be interesting to test other animals in a similar way to see whether other animals construct their words and sentences from a subset of meaningless sounds!

References

1. Pinker, Steven. The language instinct: The new science of language and mind. Vol. 7529. Penguin UK, 1995.
2. Engesser, Sabrina, et al. “Experimental Evidence for Phonemic Contrasts in a Nonhuman Vocal System.” PLoS Biol 13.6 (2015): e1002171.