Nature refers to all of the genes and hereditary factors that influence who we are—from our physical appearance to our personality characteristics.
Nurture refers to all the environmental variables that impact who we are, including our early childhood experiences, how we were raised, our social relationships, and our surrounding culture (Cherry, 2018).
The nature versus nurture debate is one of the oldest issues in psychology. The debate centers on the relative contributions of genetic inheritance and environmental factors to human development. Some philosophers such as Plato and Descartes suggested that certain things are inborn, or that they occur naturally regardless of environmental influences. Nativists take the position that all or most of our behaviors and characteristics are the result of inheritance. Advocates of this point of view believe that humans are nothing but the result of evolution. Genetic traits handed down from parents influence the individual differences that make each person unique (Zaky, 2015).
At the other end of the spectrum are the environmentalists – also known as empiricists. Their basic assumption is that at birth the human mind is a tabula rasa (a blank slate) and that this is gradually “filled” as a result of experience and learning (e.g. behaviorism). Theorists such as Watson (1930) believed that people could be trained to do and become anything, regardless of their genetic background. For example, when an infant forms an attachment it is responding to the love and attention it has received, language comes from imitating the speech of others, and cognitive development depends on the degree of stimulation in the environment and, more broadly, on the civilization within which the child is reared (Zaky, 2015).
From the foregoing, I have been able to establish clearly that behavior is a product of both nature and nurture. The next point of consideration now is, how do both interact? It is widely accepted now that heredity and the environment do not act independently. Instead of defending extreme nativist or environmentalist views, most psychological researchers are now interested in investigating the ways in which nature and nurture interact. In psychopathology, this means that both a genetic predisposition and appropriate environmental triggers are required for a mental disorder to develop. This realization is especially important given the recent advances in genetics. The Human Genome Project, for example, has stimulated enormous interest in tracing types of behavior to particular strands of DNA located on specific chromosomes. If these advances are not to be abused then there will be a need of more general understanding of the fact that biology interacts with both the cultural context and the personal choices that people make about how they want to live their lives. There is no neat and or a simple way of unraveling these different and reciprocal influences on human behavior (Zaky, 2015).
A perfect example of nature and nurture interaction is perfect pitch which is the ability to detect the pitch of a musical tone without any reference. Researchers have found that this ability tends to run in families and believed that it might be tied to a single gene. However, they have also discovered that possessing the gene alone is not enough to develop this ability. Instead, musical training during early childhood is necessary to allow this inherited ability to manifest itself (Zaky, 2015).
However, there is a contemporary view about the nature-nurture interaction. Throughout the history of psychology, this debate has continued to stir up controversy. Eugenics, for example, was a movement heavily influenced by the nativist approach. Psychologist Francis Galton, a cousin of the naturalist Charles Darwin, coined both the terms nature versus nurture and eugenics and believed that intelligence was the result of genetics. Galton believed that intelligent individuals should be encouraged to marry and have many children, while less intelligent individuals should be discouraged from reproducing.
Today, the majority of experts believe that both nature and nurture influence behavior and development. However, the issue still rages on in many areas such as in the debate on the origins of homosexuality and influences on intelligence. While few people take the extreme nativist or radical empiricist approach, researchers and experts still debate the degree to which biology and environment influence behavior.
Increasingly, people are beginning to realize that asking how much heredity or environment influence a particular trait is not the right approach. The reality is that there is not a simple way to disentangle the multitude of forces that exist. These influences include genetic factors that interact with one another, environmental factors that interact such as social experiences and overall culture, as well as how both hereditary and environmental influences intermingle. Instead, many researchers today are interested in seeing how genes modulate environmental influences and vice versa (Cherry, 2018).
Let me give a practical illustration of the debate to round off my discussion here. The case study is based on twins. There are two types of twins: monozygotic (MZ) and dizygotic (DZ). Monozygotic twins, also called “identical” twins, result from a single zygote (fertilized egg) and have the same DNA. They are essentially clones. Dizygotic twins, also known as “fraternal” twins, develop from two zygotes and share 50% of their DNA. Fraternal twins are ordinary siblings who happen to have been born at the same time. To analyze nature–nurture using twins, we compare the similarity of MZ and DZ pairs. Sticking with the features of height and spoken language, let’s take a look at how nature and nurture apply: Identical twins, unsurprisingly, are almost perfectly similar for height. The heights of fraternal twins, however, are like any other sibling pairs: more similar to each other than to people from other families, but hardly identical. This contrast between twin types gives us a clue about the role genetics plays in determining height (Lumen Learning, 2018).
Now consider spoken language. If one identical twin speaks Spanish at home, the co-twin with whom she is raised almost certainly does too. But the same would be true for a pair of fraternal twins raised together. In terms of spoken language, fraternal twins are just as similar as identical twins, so it appears that the genetic match of identical twins doesn’t make much difference (Lumen Learning, 2018).
References
Cherry, K (2018).The Age Debate of Nature vs. Nurture. Retrieved from https://www.verywellmind.com/what-is-nature-versus-nurture-2795392
Lumen Learning (2018).The Nature-Nurture Question. Retrieved from https://courses.lumenlearning.com/waymaker-psychology/Article/the-nature-nurture-question/
Zaky EA (2015) Nature, Nurture, and Human Behavior; an Endless Debate. J Child AdolescBehav 3:e107. doi:10.4172/2375-4494.1000e107