Listen closely to those baboon calls. They may tell you a thing or two about human speech. Scientists who studied baboons’ wahoos, yaks, barks and other vocalizations have found evidence of five vowel ...

Does [a:] as in 'baa' sound more green or more red? And is [i:] as in 'beet' light or dark in color? Even though we perceive speech and color are perceived with different sensory organs, nearly ...