 It is also linked to the development of linguistic skills and the development of certain neurological disorders like ADHD.Delbert D. Thiessen said that "Homo sapiens" are more neotenized than "Homo erectus", "Homo erectus" was more neotenized than "Australopithecus", Great Apes are more neotenized than Old World monkeys and Old World monkeys are more neotenized than New World monkeys.Nancy Lynn Barrickman said that Brian T. Shea concluded by multivariate analysis that Bonobos are more neotenized than the common chimpanzee, taking into account such features as the proportionately long torso length of the Bonobo.