Discovering the secret of marmosets’ communication: they have names

A new study from the Hebrew University reveals that marmosets use specific calls, called “phee-calls,” to name each other, a behavior previously limited to humans, dolphins, and elephants. The discovery highlights the complexity of social communication in marmosets and suggests that their ability to name each other vocally could provide valuable insights into the evolution of human language.

The ability to name others is a highly advanced cognitive ability observed in social animals, and until recently it was known to exist only in humans, dolphins, and elephants. Interestingly, our closest evolutionary relatives, non-human primates, seemed to lack this ability altogether.

In a new study published today in ScienceA team of researchers from the Hebrew University, led by Dr. David Omer of the Safra Center for Brain Sciences (ELSC), has made a groundbreaking discovery: for the first time, they have discovered that marmoset monkeys use phee calls to name each other.

To uncover this phenomenon, the researchers, led by graduate student Guy Oren, recorded natural conversations between marmoset pairs, as well as interactions between the monkeys and a computer system. They found that the monkeys use their “phee” calls to address specific individuals. More interestingly, the marmosets could discern when a call was being made to them and responded more accurately when it was.

“This discovery highlights the complexity of social communication among marmosets,” says Omer. “These calls are not just for self-location, as previously thought: marmosets use these specific calls to label and address specific individuals.”

The study also found that members of the same marmoset family use similar vocal labels to address different people and employ similar sound characteristics to encode different names, similar to the use of names and dialects in humans. This learning appears to occur even in adult marmosets that are not related by blood, suggesting that they learn both the vocal labels and dialect of other members of their family group.

Researchers believe these types of calls may have evolved to help marmosets stay connected in their dense rainforest habitat, where visibility is often limited. By using these calls, they can maintain social bonds and ensure group cohesion.

“Marmosets live in small, monogamous family groups and care for their young together, much like humans do,” Omer says. “These similarities suggest that they faced evolutionary social challenges similar to those of our early prelinguistic ancestors, which may have led them to develop similar methods of communication.”

This study provides new insights into how human social communication and language may have evolved. The ability of marmosets to label each other with specific calls suggests that they evolved complex brain mechanisms, potentially analogous to those that ultimately gave rise to language in humans.

This study opens exciting avenues for further research into how our own communication abilities may have evolved and what we can learn from these non-human social primates.