Marmosets, tiny monkeys who live in tight-knit family groups, communicate using whistles called 'phee calls'.
A groundbreaking study has found that these monkeys use distinct 'phee calls' to address specific individuals, just like we use names.
This is the first time this type of vocal labeling has been observed in primates other than humans and dolphins, and it's thought to help maintain social order within the group.
This research could change how we understand the evolution of language, showing how vocal learning might be more common in primates than we previously thought.