New research shows that young chimpanzees combine different gestures, sounds, and facial expressions to reflect how communication develops in infants. The study, led by psychologists at Durham University, suggests that these combinations of different communication signals could potentially increase the clarity of their messages to other chimpanzees, particularly in various contexts such as play or conflict. Researchers have found that this ability develops during childhood and adolescence.
Such combined cues included the combination of a playful, gaping face with laughter, touching another chimpanzee while whining, and showing teeth while gnashing. The researchers say that understanding this “multimodal” form of communication could shed important light on how communication evolved in humans and our closest ape relatives, and could give us more insight into how our own language abilities emerge.
Their research, which includes the University of Portsmouth, has been published in the journal. Animal Behavior. Researchers observed 28 semi-wild chimpanzees aged one to 11 years old at the Chimfunshi Wildlife Orphanage Trust in northern Zambia. Whereas previous research in great apes had mostly examined different forms of communication signals (gestures, vocalizations, facial expressions) alone, the new findings examined how chimpanzees combine these different forms of communication and how this evolves with age and under different conditions.
The researchers found that chimpanzees consistently use independent communication signals such as grunts, hand gestures or facial expressions at different ages and in different situations. However, they also showed that as chimpanzees age, they are more likely to combine different communication signals.
This was especially true when the researchers responded to aggression or playing games, two situations where it’s important to be clear about what they’re talking about to avoid risky consequences. The older adolescent chimpanzees studied were more likely to use a combination of different communication signals rather than single gestures or expressions, especially during aggression scenarios.
Emma Dougherty, a PhD student in Durham University’s Department of Psychology, said: “When we think of human language, we know it’s a combination of different types of communication, such as speech, facial expressions and gestures.
“The way we communicate probably has deep evolutionary roots shared with some of our closest living relatives, such as apes.” Our study provides evidence that the way chimpanzees communicate in a more complex way as they age is consistent with the communication development we observe in infants.
“By examining the evolution of this multilayered communication pathway in young chimpanzees, we can learn more about its causes and shed light on the potential evolutionary continuum between humans and other apes.”
More work is needed to observe multimodal signals in primates in the wild to better understand how communication development is affected by different environments, the researchers said. They added that examining multimodal communication rather than observing individual communication signals in isolation could provide better evidence of how communication evolved in great apes and potentially help us understand the evolution of human communication.
Study author Dr Zanna Clay, Associate Professor of Psychology at Durham University, said: “Many studies on communication in both humans and other animals have examined individual communication signals independently, but we know that humans combine these signals continuously from early childhood.
“As close relatives of humans, the great apes give us a snapshot of how these signals may have evolved into multimodal communication that eventually reaches human language.” Source
Source: Port Altele
