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Fields of science, philosophy, physiology and psychology share a commonlanguage which is oNen quite disparate in meaning. Consider the “witticism” by George Bernard Shaw that England and the United States are two countries separated by a common language. But, what of our cousins? How well do other primates communicate? Communication by facial expression has been documented in great apes, noting even their use of their upper extremities for social gestures, similar to that of excited.
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Bruce Rothschild (2016) studied this question.
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