Instinct theories of aggression would have the most difficulty accounting for 1.biochemical influences on aggression. 2.silent and social aggression in animals.3.unprovoked outbursts of aggression. 4.wide variations of aggressiveness from culture to culture.

4.wide variations of aggressiveness from culture to culture.

Explanation:

According to instinct theory of aggression, aggression is an innate trait and people are born with varying levels of it. It is a result of biological drive for protecting ourselves from danger and is instinctual.

Instinct theory focuses more on the innate property of aggression thus it has most difficulty in explaining the effect of culture and environment on it. People in different cultures show different levels of aggression which can not be explained just on biochemical or genetic terms. Even two identical twins born and brought up in different culture might exhibit different levels of aggression.