For decades psychologists have debated whether nature or nurture is more important to human development. The argument revolves around the importance of the contribution between inherited versus environmental factors. John Stiles expressed in Brain Development and the Nature Versus Nurture Debate that philosophers like Plato were known as nativists (14). Nativists assume that the majority of behaviors are inherited and a direct result of genetic influence. Plato postulated that certain characteristics were inherited and would emerge regardless of an individual’s environment, or nurturing. Others, such as the well-known John Locke, believed in tabula rasa, which means that the mind is a blank slate beginning in infancy. This philosophy suggests that nothing is inherited, and all behaviors are born out of environmental influences and experiences (15). These individuals are known as empiricists. Controversy between the two groups arises because “nature” represents inborn characteristics while “nurture” refers to behavioral training, and it can be difficult to ascertain whether a characteristic was inherited with a person or if they learned it (5).
In an effort to end such controversy, many studies have been conducted in order to distinguish between which holds more sway over us: nature or nurture. One such study followed 119 sets of twins: 50 fraternal sets raised together; 50 identical sets raised together, and 19 identical sets raised separately. The aim of the study was to study the impact nature and nurture had on the twins’ physical characteristics, personality, and temperament. According the James Brank the subjects raised together represented the primary impact of nurture while the subjects raised apart tested the hypothesis that nature and inherited behaviors would be the strongest factor in the development (363). Another study, performed by Irene Elm, Bernard Learner, and Michael Byre, aimed to test nature versus nurture was performed on 100 musically gifted children (196). 50 grew up in their own homes with their biological parents, and 50 had been placed in foster homes, adopted, and accepted into programs for musically gifted children. The adopted children used in the study were chosen only because their birth parents were successfully found. The aim of the study was to understand whether nature or nurture was more responsible for a child’s musical abilities If the adopted children had biological parents who were also musically gifted it would suggest that inherited characteristics and nature were responsible for our behaviors (197). However if the parents raising their biological children had no musical talent but instead fostered an environment where learning and creative expression were encouraged, the results would propose that environment and nature dictated our behaviors more than inherited factors.
The two studies are similar because they attempt to test the importance of nature versus nurture through by observing children raised in and out of their biological homes. This is in an effort to test which is stronger between inherited characteristics and environmental factors. Both studies are different for several reasons. The nature versus nurture study performed on twins is unique because twins are already very similar. Studying sets of twins reared together and sets of twins raised apart gives a more representative example of whether nature or nurture is stronger in development. If children raised away from their parents or siblings still take on characteristics of biological relatives nature may play a bigger role than nurture. This study also seeks to differentiate between general characteristics instead of one specific characteristic or talent. The study performed on musically gifted children seeks to understand if talents can be fostered by environmental factors or if they have to be inherited.
The studies yielded interesting results. Final calculations for the study performed on the 119 sets of twins confirmed what was already well known: identical twins are more alike than fraternal twins. Fraternal twins share similar characteristics but lack certain abilities identical twins have. For example identical twins can often feel when the other is in distress. This suggested the genetic link between identical twins is stronger than the one between fraternal twins. The genetic link provided added support to nature being stronger than nurture because even sets of identical twins raised separately were sometimes able to tell when one or the other was experiencing distress. However, analysis based on correlation, modified variances, and case studies performed on twins reared apart all expressed that nature had the least impact on physical features while impacting temperament and personality the most. Though identical twins could sense each other’s feelings, 9 of the 19 sets raised apart had juxtaposing behavior, proposing nurture overwhelmed their upbringing . The remaining sets acted similar, advocating nature is more important because separation did not sever their genetic bond. Overall, because the resulting numbers were so close, the results of whether nature or nurture proved a stronger influence were inconclusive. The results of the studies performed on musically gifted children were also inconclusive. 25 of the 50 adopted children came from biological parents who showed musical talents. The other 25 children had parents who did not display some form of musical talent. 50 percent of the adopted children, both with and without a genetic predisposition for musical talent were placed in homes that did not place any special emphasis on creative expression. 15 of the children being raised by their biological parents were being raised in homes that promoted creative expression and 10 came from homes where parents with musical inclination were present. Children born to biological parents with musical inclination played no better than children born to parents without musical inclination. The same results were found in children brought up in expressive homes versus those brought up in more conservative atmospheres. Children brought up in homes that encouraged creative expression played no better than children brought up in more conservative atmospheres. Due to variances in genetic markers, home atmosphere, and overall talent the results suggested that a musical talent could be easily either inherited or learned.
Because these and other studies have consistently drawn inconclusive results over time, it controversy continues to run heavily between the participants of this debate. One could argue that we are only a product of our genetics. We would have no control over our behaviors because they would all be inborn within us. It would not be difficult to prove this; many people act like their family members without spending much time with them. However one could also argue that nurture is more important and our behavior can be trained. Some psychologists believe that inherited traits and environmental factors have equal influence on us . The inconclusive data of so many studies would suggest that some of our qualities are inherited while others are learned. Whichever side a psychologist takes, one thing is certain; there is no end of this debate in site.
References
Brank, & James. (1994). The Impact of Heredity and Environment on Twins. American Psychological Association, 362-370.
Elm, I., Learner, B., & Byre, M. (2001). Nature Versus Nurture: The Face of the Musically Talented Child. American Psychological Association, 196-198.
Stiles, J. (2011). Brain Development and the Nature Versus Nurture Debate. Elsevier.
