Statistical comparisons of the SCC orientation between humans, chimpanzees and bonobos.

Angles measurements and angles comparisons between species showing subtle differences between humans and bonobos and marked differences with chimpanzees (NS = not significant, H = humans, B = Bonobos, C = Chimpanzees). Anterior, posterior and lateral SCC were referred to as ASCC, PSCC and LSCC. (*) parametric tests were used since angular measurements showed normal distribution. (**) non parametric tests were used since angular measurements did not show normal distribution; however parametric tests results were consistent with those of non parametric tests. All angles in degrees.