Even if juveniles acquire sex-specific adult-like foraging skills before reaching adult size, their smaller body size may put them at a foraging disadvantage. […] The size effect on foraging is reduced in species that use small or easily manipulated substrates. For instance, in Costa Rican squirrel monkeys, juveniles apparently mastered techniques for insect foraging only a few months after weaning, when they were still much smaller than adults[…].