Syntax in Our Primate Cousins

ScienceDaily (Dec. 13, 2009) — A study carried out in Ivory Coast has shown that monkeys of a certain forest-dwelling species called Campbell's monkeys emit six types of alert calls. The primates combine these calls into long vocal sequences which allow them to convey messages about social cohesion or various dangers, including predation.

This study shows the capacity of this monkey species for very complex vocal communication, both in the range of transmitted messages and in the techniques used to encode these messages.
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In this new study, the ethologists explain some of the rules that govern the semantic combinations of calls. For example, Campbell's monkeys can add a particular type of call to an existing sequence in order to make the message more precise or to alter it. They can also combine sequences relaying different messages in order to convey a third message.