Apes use complex body language

Animal communications: Chimps and gorillas are quite the conversationalists, provided you take a broad view of what is meant by communication. Touch, gestures, grimaces and grunts are all part of the vocabulary, so long as you have the skills to understand what is being said.

How apes conduct these surprisingly complex exchanges provided the subject matter for a session at the BA Festival of Science, entitled "Primate Social Cognition: What Monkeys and Apes Know and Feel about Each Other".

It is all about body language, explained Dr Gillian Sebestyen Forrester of the University of Sussex. "Body language is the signals through which we achieve non-verbal communications with one another," she said.

Humans are relatively poor at reading messages in body language compared to our ape cousins, who add to this touch and gestures.

Dr Sebestyen has recently started a study to record and interpret exchanges between gorillas. It involves using two video recorders, one focused on the ape giving the signal and another recording how the recipient responds.

It is a complex endeavour, given her description of a single exchange between a pair of gorillas that included sounds, touch and hand-waving.

She said it involved "multimodal signals" and "vocalisations are just a small piece of the pie".

Her video data were only beginning to undergo study so she had no hard information about the meanings of gestures or the extent of the gorilla vocabulary.

The University of Portsmouth's Dr Kim Bard discussed emotional communicative development in chimpanzees. "We learn more about our development if we compare with other non-human primates," she said.

She studies in particular how baby chimps engage emotionally with their carers, both chimp and human.

There are many similarities in the response of chimps and human babies to carer actions. If the carer frequently plays with the chimp, it will smile more often. The chimp will laugh if tickled and, as with a human baby, it does better with plenty of stimulation.

If the baby chimp spends the first 30 days of its life with its mother, it will frequently smile at her, but not at a friendly human carer. But the smiles are reserved for the human carer if the chimp is handled from birth by a human.