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One word, sounds like . . . Photo credit: University of St. Andrews

Science Daily:

When using gestures to get their points across, orangutans rely on the same basic strategy that humans follow when playing the popular game and intentionally modify or repeat hand (or other) signals based on the success or failure of their first attempt.

Professor Richard Byrne of the (University of St. Andrews) School of Psychology said, "We were surprised that the orangutans' responses so clearly signaled their assessment of the audience's comprehension. Looking at the tapes of the animal's responses, you can easily work out whether the orangutan thinks it has been fully, partially, or not understood, without seeing what went before."

"This means that, in effect, they are passing information back to the audience about how well they are doing in understanding them, hence our 'charades' analogy. In playing the game, you want primarily to convey your meaning non-verbally - as does the orangutan - but secondarily to help the team get your meaning by giving them hints as to how well they are doing."