Animal Communication Researcher Discovers Nuances in Animal Calls and Gestures
In a recent breakthrough, Toshitaka Suzuki, an ethologist at the University of Tokyo, has found a method to distinguish intentional calls from involuntary ones in animals. Suzuki, who refers to himself as an animal linguist, stumbled upon this discovery while taking a bath one day. He realized that words have the ability to influence how we see objects, while sounds do not. He used playback studies to determine that Japanese tits emit a specific vocalization when they encounter snakes, which he named the “jar jar” call. When other Japanese tits heard a recording of this call, they searched the ground, as if looking for a snake. Suzuki then conducted an experiment using a stick to further test the influence of the “jar jar” call. Typically, the birds ignored the stick, treating it as a passing cloud. However, when the recording of the call was played, the birds approached the stick, as if examining whether it was a snake.
Similarly, Cat Hobaiter, a primatologist at the University of St. Andrews, has developed a nuanced method to study animal communication. Hobaiter focuses on studying the gestures of great apes, as they have a relatively limited repertoire of vocalizations. She has spent years following chimps in the Budongo forest and gorillas in Bwindi, recording their gestures and how others respond to them. To determine whether these gestures are involuntary or intentional, she uses a method inspired by research on human babies. Hobaiter looks for signals that evoke an “Apparently Satisfactory Outcome.” Involuntary signals continue even after the listener has understood their meaning, while intentional signals stop once the signaler realizes the listener has comprehended the signal. By analyzing thousands of instances of gestured exchanges between apes, Hobaiter has identified dozens of gestures that trigger “apparently satisfactory outcomes.”
Intriguingly, Hobaiter’s research indicates that these ape gestures may also be understood by humans, albeit at a subconscious level. She applied her technique on pre-verbal 1- and 2-year-old children and found that they use many gestures from the ape repertoire. Furthermore, when she posted video clips of ape gestures online and asked adults who had never spent time with great apes to guess their meaning, the participants correctly guessed the meaning of the gestures at a rate significantly higher than expected by chance.
Although this emerging research suggests that there are intentional wordlike signals in other animal species, similar to human language, there are still distinct differences. While some species, like Japanese tits and pied babblers, combine different signals to create new meanings, no other species has been discovered to have a communication system with all the properties of language.
The findings of Suzuki and Hobaiter shed light on the complexity and intricacies of animal communication, indicating that animals may have their own ways of conveying intention and meaning through calls and gestures. Further research in this field may provide a deeper understanding of the evolution and nature of language.