Chimpanzees can learn “words” for objects, a study suggests.
Captive chimpanzees can learn new vocalizations to refer to specific objects from chimps raised in a different environment, according to a study published this week (February 5) in Current Biology.
In 2010, a group of chimps raised at a safari park in the Netherlands was integrated with a group at the Edinburgh Zoo in Scotland. Prior to the move, the Dutch chimps were enthusiastic about apples and used high-pitched calls to refer to them, whereas the Scottish apes voiced their displeasure for apples by referring to them with low grunts. As the two groups became more closely knit over the following three years, the chimps maintained their respective apple preferences, but a team of researchers from the Universities of York, Zurich, and St Andrews noted that the apes from the Netherlands began referring to apples with the Scottish group’s grunting.
“As far as we know, this is the first evidence we’ve seen of a referential call being modified,” study coauthor Simon Townsend of the University of Zurich told The Verge. Previously, scientists had assumed that these sounds used by chimpanzees and some other primates were closely tied to the emotions the animals had about the object, but the behavior of the chimps at the Edinburgh Zoo suggested that the sound associated with a given object can be decoupled from that item’s emotional value. “This suggests that the way meaning is assigned in human language and in animals might be more similar than previously thought,” Townsend added.
“This is the first bit of evidence which might suggest that [vocal learning] . . . is a much older capability, that maybe our last common ancestor might also have had,” study coauthor Katie Slocombe of the University of York told BBC News.