Charles Darwin was not only a pioneer in evolutionary psychology, also today’s theories of modern lifespan development draw on and are influenced by Darwin’s ideas. His functionalist perspective primarily focused on the reason for development of specific human characteristics over many generations, and therefore an enormously long timescale. However, inspired by the observations in the development his own son, Darwin also acknowledged that “an individual is the result of a gradual sequence of prior changes, both in a broad evolutionary sense and within individual’s own lifetime and further development and changes lies ahead” (Cooper and Roth, p.50, 2003). This notion provided the basis for other researchers to further explore the development of humans over a lifetime period.
The human lifespan development can be explored in many different ways, e.g. in terms of biological maturity of the body from a new-born to a physically fully-grown adult, physical deterioration in later stages of live and how that effects people psychologically. Individual physiological and psychological characteristics are potential factors that have different impact on each individual, they therefore are considered as “internal influences” (Cooper and Roth, p.5, 2003). The development of cognitive abilities, specific historical circumstances or the social and cultural environments of each person present “external influences” (Cooper and Roth, p.5, 2003).
It has to be noted that both internal and external factors can influence each other. We therefore we have to look at these transactions rather than just taking single factors into consideration.
Initially, researchers considered the observation of children as a very instructive means in investigating at what point of time certain changes in human behaviour evolve. Through identifying a pattern of changes that take place in the development of a new born into a fully grown adult, researches developed the organismic approach. They believed that in order to achieve adulthood, people go through different phases and that a later stage incorporates and expands on the experiences from an earlier stage in life (“stage theory”). While adulthood was considered as the end-stage, external factors were identified as potential causes for a delay, acceleration or slowing-down in certain stages of development, but it was suggested that the pattern and order of developmental stages are fixed.
Jean Piaget adopted the organismic approach and based his opinion on his research on the intellectual development of children. He himself called his area of interest “genetic epistemology” (Cooper and Roth, p.5, 2003). It aimed to identifiy how human delevop cognitive capacities.
Piaget recognized that errors that children made in intelligence tests apparently occurred systematically and used these errors to identfy the mental processes in achieving cognitive abilities. He identified four stages in which children intellectually adapt to their...