What Bonobos Can Teach Us about Human Speech

International team of researchers with members from Freie Universität Berlin examines the fundamentals of language development. Researchers from Europe and the United States of America conducted a study on "sound symbolism" in primates. The experiment involved experts from Freie Universität Berlin, the University of St. Andrews, the Max Planck Institute for Evolutionary Anthropology, as well as Pennsylvania State University and the Ape Initiative. The animal subject was a language-competent bonobo named "Kanzi." The ape has drawn attention due to its ability to learn English words and match spoken words with images of objects - a basic ability required for language acquisition. In the experiment, researchers would play nonsense syllables, for example "kiki," for Kanzi and show him corresponding abstract shapes that were either angular or curved. In human trials, subjects showed a tendency to pair sharp sounding pseudowords like "kiki" with angular shapes, whereas soft sounding pseudowords like "bouba" were frequently associated with curved shapes. This connection between sounds and abstract symbols is known as "sound symbolism." Kanzi, however, did not demonstrate this matching preference in the experiment, which did not come as a great surprise, given that other great apes also fail to connect sounds and shapes in this manner.