Researchers say marmoset monkeys call each other by name, similar to how humans recognize each other. The 20-cm-long primates are native to South America. Scientists from the Hebrew University of Jerusalem studied the social interaction of 10 marmosets. The research team discovered that the animals used unique calls for other monkeys in their group. Dr David Omer, co-author of the study, said marmosets are the first non-human primates known to use names. The researchers put the marmosets in a variety of pairings. They then used artificial intelligence to analyze more than 50,000 monkey calls. This allowed the scientists to determine the animals had names for each other.

Dr Omer believes the findings could shed light on how human language evolved. He said: "Until quite recently, people thought that human language was a singular phenomenon that popped out of nothing. We're starting to see evidence that this is not the case." Omer postulated how marmosets developed a system of name calling. He said: "Marmosets live in small, monogamous family groups, and take care of their young together, much like humans do. These similarities suggest that they faced comparable evolutionary social challenges to our early pre-linguistic ancestors." Other creatures known to identify others in their group by name are dolphins and elephants.