Origins of Human Communication – UCLA Study Provides One Line of Evidence

Scientists from the University of California in Los Angeles reveal that when it comes to the study of language, young toddlers and apes have lessons to teach researchers about the origins of human communication and how it evolved. This group of researchers discovered that there are similarities in how young human children and primates communicate. The study was published in the journal Frontiers in Psychology.

The research proponents wrote in the paper that the most basic finding of the study is the similarity of gestures among the three species “at comparable periods of development.” The findings of the study, based on a year’s worth of videos on three species are essentially pointing to evidence that “language evolved from gestures.”

The language of our common ancestors: vocalizations, gestures, and lexigrams or visual symbols

The proponents intended to add to the available knowledge base on how spoken language evolved in human beings. The researchers looked for similar features on how the three species communicate with each other. They wanted to determine how the common ancestors of primates and humans were communicating more than five million years ago.

The young primates used in the study were raised at the Atlanta Language Research Center. Sue Savage-Rumbaugh, the co-director of the facility is a co-author of the study. The chimpanzee and bonobo learned to communicate using vocalizations, gestures, and lexigrams or visual symbols. Lead author Kristen Gillespie-Lynch clarified that the young primates were taught to communicate during meaningful interactions in a social context and not from behavioral training. Meanwhile the human toddler grew up at home with her parent and an older brother.

Something in common

Psychologists from the UCLA used video footages of a bonobo called Panbanisha, a chimpanzee called Panpanzee, and a young girl simply called by her initials “GN.” The study is the first of its kind involving the comparison of the development of gestures in humans, bonobos, and chimpanzees. What they found out is that when learning to communicate, all three young female subjects initially use gestures. Eventually, they use symbols more than gestures, but the shift from one form to another is more obvious in the human child. Eventually all three species increase use and production of symbols. The human subject use words while the primates use shapes.

According to one of the authors of the study, Prof. Patricia Greenfield, a psychology professor at UCLA, the observations gleaned from the study are a “new kind of evidence” that “speaks to the idea that gestures and vocal language or speech evolved together.”

Similarities observed

Some of the universal gestures observed in all three species are pointing with the head or “head point” gesture, pointing with the index finger, reaching wherein the subjects leaned toward an object or person without physical contact, and raising the arms over the head to be picked up or “up gesture.” Because the gestures were consistently paired with vocalization, eye contact, or persistence, they were considered “communicative.”

Other communicative gestures observed are the “reach-touch” gesture wherein the subjects make contact with the object of desire (e.g. snack), the “point-touch” gesture using the index finger wherein it makes contact with the page of a book, and the “go” gesture which is similar to reaching and pointing except for a lack of specific nearby target.

Photo Credit: Female toddler