Fig. 3. The age at which adult-level skill competence in food manipulations is reached is highly correlated with the complexity of the adult manipulation repertoire and with adult brain size.
Relationship between age at adult-level skill competence [in ln (days)] and (A) the complexity of the adult manipulation repertoire and (B) adult brain size [in ln (cm3)] for 36 primate species. Skill competence in food manipulation is reached later in species with a more complex adult manipulation repertoire and with a larger adult brain size. Species values are listed in table S1.