A recent study reveals that genetic factors play a more pivotal role in the aggressive nature of infants than environmental factors.
The researchers at CHU Sainte-Justine Hospital, under University of Montreal focused on genetic factors determining the aggressive nature in children. However, these genetic factors can get modified and influenced by the other environmental pressures causing changes in behavior.
The researchers have derived their findings out of a detailed analysis made on twins born between April 1995 and December 1998 in Montreal, Canada. The study included both genetically identical monozygotic twins (originate from the same embryo) and non-identical dizogytic twins ( develop in separate embryos), reports dailymail.
The mothers of the little participants were asked to report about aggressive traits like hitting, biting, kicking and fighting noticed in their off springs at different ages- 20, 32 and 50 months.
According to the researchers, the differences in reactions noticed among the toddlers are due to the genetic difference in the kids.
Earlier studies have primarily focused on social factors influencing the violent nature in infants and state that such characteristics start developing at infancy and peak between the ages of two and four. But the Montreal study states that both frequency at onset and the rate of change in the tantrums shown by the infants keep on changing with time and both environment and genetics influence them.
According to the researchers, the genetic and environmental influences on the physical aggression in children often get overlooked in studies done on effects of disturbed childhood or singleton parenting resulting in aggressive nature in pre-school children.
"Genetic factors always explained a substantial part of individual differences in physical aggression," said Eric Lacourse in a press release. "More generally, the limited role of shared environmental factors in physical aggression clashes with the results of studies of singletons in which many family or parent level factors were found to predict developmental trajectories of physical aggression during preschool."
The researchers have also cautioned that negative influences from peers, parents can result in greater physical aggression in children. "Because early childhood propensities may evoke negative responses from parents and peers, and consequently create contexts where the use of physical aggression is maintained and reinforced, early physical aggression needs to be dealt with care,"
