In a study published on Tuesday in Nature Communications, evolutionary biologists at The Graduate University for Advanced Studies in Japan, the Uppsala University in Sweden and the University of Zurich in Switzerland, have now demonstrated that the Japanese great tit, a songbird, uses developed syntax in their bird calls, a skill previously thought to be unique to humans.
These small birds are known for their large vocal repertoire, and the team discovered that they use a variety of calls and combinations of calls to interact with one another in specific situations. For the new study,the researchers focused on a few of the Japanese great tit’s different note types, which are named A, B, C and D. Prior research found that when A,B, and C are produced together in that order, the call instructs listeners to “scan for danger.” The great tits use the “ABC calls” when a sparrowhawk or another predator is nearby. By contrast, “D calls” mean “come over here,” a call the birds use after discovering a new source of food or when wanting their partner to come to the nest. It is known that Japanese great tits have AC, BC, AC-D and BC-D calls, as well as probably many others, all of which are not yet understood by researchers.
Tits frequently combine these two calls into ABC-D calls when, for instance, the birds encounter predators and join forces to deter them. Warning signal plus mating call means “flock together”. When hearing a recording of these calls played in the natural order of ABC-D, the birds are alarmed and flock together. When, however, the call ordering is artificially reversed to D-ABC, the birds do not respond.
The birds seem to learn their various calls over time, with nestlings only emitting a limited number of call types associated with begging and distress. As they grow up, they copy their fathers’ mating songs and may learn their vocalizations in other ways, too.
The researchers have therefore drawn the conclusion that syntax is not unique to human language, for it also evolved independently in birds. “The results lead to a better understanding of the underlying factors in the evolution of syntax. Because the tits combine different calls, they are able to create new meaning with their limited vocabulary. That allows them to trigger different behavioral reactions and coordinate complex social interactions,” says Dr. Michael Griesser, at the Institute of Anthropology at the University of Zurich. He believes these factors may well have contributed to the development of language in humans.
It is so important in this day and age of vast information and knowledge, that we continue to recognize how much about our own natural world we truly do not understand… yet.
Happy Flyday ~^v^~