However, differential reinforcement may not be the full cause of gender differences in behaviour. Indeed, adults, during interactions with their own children, may simply be responding to innate gender differences that are already there. For example, the observation that boys are encouraged to be more active during play may be a consequence of the fact that they are naturally more active anyway, due to hormonal differences. This suggests that it is likely that social learning is only part of the explanation of how children acquire gender-related behaviours.