This winter break I visited Peru where I was fascinated by the beauty of the Amazon Jungle. Here I was able to see numerous different animals but most notably, tens of different species of birds. From colorful macaws to solid colored tanagers, the list of bird species in Peru’s Amazon was vast. Each and every bird had its own unique call, sound, or form of communication which I found out from one of my tour guides is the premise of many bird names. For example, the macaw is a vibrant and colorful bird that makes a loud, high-pitched sound that sounds like the onomatopoeia “macaw”. This topic got me curious; what makes bird calls unique from one another and how are bird calls distinguished between by different birds.

I started off by exploring the evolution of bird calls and where they were first discovered by us humans. The primary function of bird calls is to benefit both the sender and recipient of the call. Furthermore, as these bird calls have evolved they have strictly followed the process of natural selection which serves as a benefit for birds who use these calls. Another fascinating aspect of the evolution of bird calls is that they can evolve due to a process called mimicry. Mimicry is when a bird hears sounds that come from its surroundings and over time their own bird calls begin to adopt facets of their surrounding sounds. This is a process that plays a crucial role in the evolution of bird calls. Another process that can drastically effect the evolution of bird calls is called punctuated evolution which includes sudden trait divergence. Trait divergence is when a trait in a specific species veers of from the path of the traits of its ancestors. This can play an important role in bird calls as if a generation of a bird species experiences sudden trait divergence, it can form one or many new types of bird calls and sounds.

After delving into the evolution of bird calls, I took a deeper look at the grammatical and lingustic aspects of bird calls such as syntax, semantics, etc. According to Toshitaka Suzuki at the Department of Life Science at Rikkyo University, birds use a variety of compositional syntax—which is the combination of individual words to make one complex expression—as well as phonology or the process of taking meaningless phrases and turning them into meaningful ones. One primary example in the bird world is the chestnut-crowned babblers (Pomatostomus ruficeps) which combines two different “words/phrases” which on their own mean nothing, but when put together have a significant meaning.

Overall, my experience, both in the Amazon and researching the depths and truth behind bird calls, have been fascinating. I was able to wheedle my way into the world of bird calls through an introductory and superficial research on how bird calls work. I also have been able to understand the specifics of bird calls through a linguistic point of view using phonetics, syntax, and semantics. I find it fascinating that birds are so detailed in their methods of communication. What have we yet to reveal about the linguistic facets of other creatures on our planet? I guess only time will tell.

Sources

Podos, Jeffrey; Webster Michael. “Ecology and Evolution of Bird Sounds.” Current Biology, October 24, 2022. https://www.sciencedirect.com/science/article/pii/S0960982222012258.

Suzuki, Toshitaka N., David Wheatcroft, and Michael Griesser. “Experimental Evidence for Compositional Syntax in Bird Calls.” Nature News, March 8, 2016. https://www.nature.com/articles/ncomms10986.