Genetic and environmental factors interact with varying degrees of plasticity to effect developmental change. To very briefly outline the stages, or milestones of a child’s growth from birth onwards, research has identified, physical, motor, cognitive. socio-emotional, language acquisition variables, and their mechanisms, along with speed and pattern of development in terms of both population and individual differences. In spite of minor variations due to cultural and environmental factors, there is wide agreement as to what could be seen as ‘gifted’ or super-normal development and, at the other end, sub-normal or less than optimal development and functioning of children. Such differences are likely to persist into adulthood. However, the term atypical development is used more in the context of sub-normal rather than super-normal populations.
More recent research into the lower end of the scale in child development, which is a minority, and considered atypical under normal conditions, has concentrated on what have been identified as vulnerability and resilience factors. The motivation has been to identify, intervene, and actively improve the chances of accomplishment of a satisfactory life trajectory for those children identified as being in danger of failing to reach societal norms of everyday life. To emphasise the global spread of child development research and application, studies from the USA, Australia and South Africa within the last decade are cited in this essay; (Masten & Gewirtz (2006), Mutimer, Reece, and Matthews (2007), Theron (2006).
Vulnerability in children is described as risk factors, both individual and environmental hazards, which tend to result in negative developmental outcomes. Among individual characteristics are, intrauterine growth retardation, low birth weight, in-utero experience of maternal drug use, physical disability, and a variety of genetic defects. Among the immediate environmental hazards are family