Thumb signal

A thumb signal, usually described as a thumbs-up or thumbs-down, is a common hand gesture achieved by a closed fist held with the thumb extended upward or downward in approval or disapproval, respectively. These gestures have become metaphors in English: "The audience gave the movie the thumbs-up" means that the audience approved of the movie, regardless of whether the gesture was actually made. == History == === Natural human behaviour === While the exact source of the thumb gesture is obscure, a number of origins have been proposed. Carleton S. Coon, having observed Barbary apes in Gibraltar using the gesture, hypothesised in the anthropological classic The Story of Man that it is a mutual celebration of having opposable thumbs. Critics have suggested, however, that the apes may be simply imitating humans. === Ancient Rome === The Latin phrase pollice verso is used in the context of gladiatorial combat for a hand gesture used by Ancient Roman crowds to pass judgment on a defeated gladiator. Now they give shows of their own. Thumbs up! Thumbs down! And the killers, spare or slay, and then go back to concessions for private privies.