So our ability to distinguish "man bites dog" from "dog bites man" hinges on the attention that we pay to ordering and grouping, that allows us to get two different meanings out of the same set of words.

FORBES: Steven Pinker On Why We Have Language

Half of the gestures Dr Pollick and Dr de Waal regularly observed seemed to have completely different meanings in the two species.

ECONOMIST: Evidence that the first words were movements, not sounds