Neoteny of the genitals is marked by the absence of a baculum (penis bone) the presence of a hymen and the forward-facing vagina. Neoteny of the human body is indicated by glabrousness (hairless body). Neotenic features of the head include the globular skull thinness of skull bones the reduction of the brow ridge the large brain the flattened and broadened face the hairless face hair on (top of) the head larger eyes ear shape small nose small teeth and the small maxilla (upper jaw) and mandible (lower jaw). Adult humans more closely resemble the infants of gorillas and chimpanzees than the adults of those animals. This trend is greatly amplified in humans especially when compared to non-human primates. Neoteny in humans is the retention of juvenile traits well into adulthood. This implies that proportionately large heads and proportionately short legs would be neotenous features for adults. The human head becomes proportionately smaller and the legs become proportionately longer as humans mature.
