Great apes may have been laughing with a similar rhythm to modern humans for at least 15 million years, a University of Warwick study reveals. The finding offers unexpected clues to how human speech evolved. Great apes may have been laughing with a similar rhythm to modern humans for at least 15 million years, a University of Warwick study reveals. The finding offers unexpected clues to how human speech evolved. All living great apes—chimpanzees, bonobos... [2897 chars]