Dog Socialization: How To Avoid A Problematic Canine That Attacks Other Pets And People! ... The Critical Period The critical period of socialization is that time when a certain set or patterns of genetically oriented behavior must be performed or presented to a developing animal (in this case a puppy) in order for such behavior to manifest in the animal when it is older. The inability to initiate such genetically programmed behavior during the critical period can result in the complete corruption of hereditary behavior characteristic to that particular species of animal...