Nepalese craftsman, Chandra Bahadur Dangi, holds the record as the world's shortest adult, at 54.6 cm (1 ft 9 ½ inches). The tallest human is Sultan Kösen, a Turkish farmer, almost five times taller at 2.52 meters (8 feet 3 ¼ inches). In nature, size differences among males of a single species are not uncommon, but in a new paper, a team from the Smithsonian Tropical Research Institute (STRI), The University of Auckland and the University of Arizona, discovered a case of male beetles that are not only extremely different in size, but also provide an answer to long-standing puzzle in evolutionary biology: how can larger animals afford the energetic cost of making and maintaining disproportionately large weapons?