CONCLUSION
No single pathway is sufficient to explain the development of aggressive behavior, nor is there a single prototype of an aggressive preschooler. New research findings reveal that the critical window for intervention should be in early years (Tremblay et al., 2004). There are still many unanswered questions. Why are some children resilient? Which pathway to aggression has the most impact and which is most predictive? Aggression may have a genetic component, and similarly, the environment in which an infant/preschooler is raised may influence the development of aggressive tendencies. Researchers today are emphasizing the interplay between genetics, the environment and developmental influences. Caution must nevertheless be exercised in making simplistic statements about genetic and environmental causes when explaining the origins of aggression (Rutter, 2002). The eight pathways reviewed are related to the early routes of aggression in infants and preschoolers. This is by no means an exhaustive list of factors related to the origins of aggression in early years. However, it does provide us with an opportunity to offer programs for prevention and intervention that will preserve the uniqueness of the child.