Human Language May Have Evolved from Birdsong: New Meaning for Communication

Humans and birds may have more in common than we once thought. Researchers from MIT, along with a scholar from the University of Tokyo, suggest that human language is a grafting of two communication forms found elsewhere in the animal kingdom--one of them being birdsong.

The findings build upon previous work that was conducted by the researchers at MIT. In particular, the researchers examined the idea that there are two "layers" in all human languages. There's an "expression" layer, which involves the organization of sentences, and a "lexical" layer, which involves the actual content of the sentence.

The researchers analyzed animal communication and used this previous research in order to discover that birdsong closely resembled the expression layer of human sentences. While bees and primates seem to mainly use the lexical layer--that is, they communicate to transfer a piece of information--birds seem to focus more on expression.

For example, birdsong itself lacks a lexical structure. Instead, birds sing learned melodies where the entire song has one meaning, whether it's about mating, territory or other things. Yet birds can create different melodies to convey their meaning. In particular, a nightingale may be able to produce anywhere between 100 to 200 different melodies. This contrasts sharply against other animals that don't have the same melodic capacity--bees use precise movements to convey their meanings, while other primates use a range of sounds to convey theirs.

The researchers hypothesized that it was certainly possible between 50,000 to 80,000 years ago that humans may have merged the two different types of expression into the form of language that we use today.

That's not to say that these results are conclusive. Future research needs to be conducted, and the current paper that shows these results is based on hypothetical studies. Researchers hope to examine communication patterns of other species in further detail as their research continues. However, the idea that humans could have created language from these two forms of distinct communication is certainly one that should be explored.

The paper was published in the journal Frontiers in Psychology.