The chimpanzees living here at CHCI are certainly exceptional with the ability to use American Sign Language to communicate both with their human caregivers and with each other. However, communication is, by no means, limited to the use of their acquired human language. Just like humans chimpanzees communicate through a variety of methods that include vocalizations, facial expressions,
posture, touch and movement.
As many of us can attest to, facial expression can be crucial in determining the context of a given situation! This is also true for chimpanzees. One common misconception, given many of our other similarities, is that chimpanzee facial expressions are the same as human ones, particularly a friendly face or, as humans call it, the smile. However, in this instance the often subtle differences in behavior between humans and chimpanzees are significant. The facial expression that humans use and recognize as a smile means something quite different to a chimpanzee. When a chimpanzee shows all of his or her teeth clenched together in what looks like a human smile that chimpanzee is actually communicating fear, excitement or attempting to threaten. Instead of this ‘fear grimace’ a playful facial expression for a chimpanzee involves a drooped lower lip and, usually, an open mouth rather than a closed one.
Here is an excellent example of Dar’s play face as he is engaged in a game with caregiver Lisa Lyons.
It is difficult to see in the picture above but Lisa is also using the chimpanzee play face rather than a human smile. The picture below shows caregiver Lindsay Zager using a play face more clearly during a game with Loulis.
Learning and using chimpanzee behaviors to facilitate more positive interactions is one of the unique experiences of anyone who is involved at CHCI whether you are a one-time chimposium visitor or a permanent fixture.