Nature versus Nurture

Nature versus Nurture: Which is More Influential to Our Life Traits?

It is a fact of life that we are products of heredity and environment. But in the debate of which has more influence in our life traits, I would say it would be the environment, or the “nurture” aspect of our development.

In the study of development, nature refers to inherited (genetic) influences on growth and functioning. Some inherited characteristics appear in virtually everyone. For instance, almost all children have natural talents for upright locomotion (walking, running, etc.), language, imitation, and the use of simple tools. Other inherited characteristics differ from one inpidual to another: these include stature, physical appearance, and athletic ability. In some studies, psychological traits as temperament (e.g., the tendency to be shy instead of outgoing), aggression, and intelligence may also be partly influenced by genetics (Petrill & Wilkerson, 2000).

On the other hand, nature’s partner is nurture, the influence of factors in human environments. Nurture includes the effects of family, peers, schools, neighborhoods, culture, the media, the broader society, and the physical environment. Nurture affects children’s development through multiple channels—physically through nutrition and activity; intellectually through informal experiences and formal instruction; socially through adult role models and peer relationships.

Historically, Francis Galton was the first to introduce the phrase “nature versus nurture,” and although he clearly favored the former as an explanation of human behavior, he had little direct evidence to support his bias. Nevertheless, Galton’s contributions, admittedly with substantial subsequent modification, are those still used today for studying heredity, and hence the role of genes, in human populations. He was also among the first to recognize that the offspring of parents representing one extreme or the other of a given trait within a population tend to be more like the average for the population than do their parents.

This “reversion to the mean” led Galton to doubt for awhile the possibilities of selective breeding as a means of altering human phenotypes. Galton was also the first to recognize the unique possibilities offered by the study of twins in matters relating to human genetics, although he never really pursued this possibility. By the end of his studies Galton was convinced that most human traits are indeed heritable. Although contemporary scientists would be unlikely to find his results compelling in terms of the data he had at hand, his various publications on the subject stimulated others to take up where he had left off (Cary 2004, p. 227).

No doubt that nature and nurture are inextricably intertwined in their effects on human development. While theorists continue to debate the relative influences of nature and nurture, people usually manage to combine these forces skillfully and naturally. For example, imagine an adolescent girl who is growing rapidly, thanks to genetic instructions activated by puberty (nature); she is also fueled by tasty meals prepared by her parents and extended family (nurture). She is less inclined to be athletic compared to many of her peers (nature) but still joins the girls’ basketball team because she is encouraged to do so by her best friend (nurture).

In my case, growing up in an American society, which is quite liberal, I assume the traits of the environment where I had been brought up. I had learned to become independent and my mindset had been shaped by the American ideologies and norms. But, what if I was born in India? Maybe, my life traits and mindset would entirely be different, since the culture in that country is different from America. My hereditary traits are already given, since my human capabilities will be the result of the genes passed on from my parents. However, the life traits that I developed have been entirely the result of the environment that I had been accustomed in.

Indeed, “nurture” is more likely to develop our life traits and personalities because majority of it is influenced by our environment. People’s personalities can be described in a variety of ways. Some people seem to be perfectionists; they can be critical, impatient, demanding, and intense. Other kinds of people are more relaxed and easygoing. You may have friends who always seem to have something to smile about and are fun to be around. Or perhaps you have friends who are shy and quiet; they are hard to get to know and may sometimes seem dull. In each of these examples, we are describing what people are generally like without referring to their specific feelings, thoughts, and behaviors in any given situation.

In formulating a general description of someone, we try to pinpoint something that is relatively enduring about the person, something that seems to explain the regularities or patterns we observe in the way the person thinks, feels, and behaves. This is because personality is the pattern of relatively enduring ways that a person feels, thinks, and behaves. Personality is an important factor in accounting for why people act the way they do in societies and why they have favorable or unfavorable attitudes toward other people.

In the life of each person, biological and social-environmental-cultural influences interact in the development of the personality system. If inpiduals are genetically and temperamentally disposed toward greater aggressiveness, for example, they soon become more likely to interpret the motives of other people as aggressive and to anticipate aggression from others (Dodge, 1986). They also may confirm these expectations and beliefs by behaving more aggressively, thereby evoking more aggressive reactions. Likewise, as aggressiveness becomes an established pattern, it also may be incorporated into the values and self-standards and goals of the inpidual.

Each time the aggressive pattern is activated, it becomes more easily accessible in the system as a dominant response tendency, triggered even by minor frustrations and stress. Increasingly the person also may seek out peers and groups likely to further support this type of behavior and to strengthen it as a source both for self-esteem and peer approval. A common example is when aggressively inclined adolescents are drawn to like-minded peers in aggressive groups and gangs that then collectively and mutually further support their aggressive tendencies.

In sum, as the example suggests, the early behavioral tendencies in the person interact with the psychological environment over the course of time as personality develops and becomes expressed in relatively stable ways (Contrada, Leventhal, & O’Leary, 1990). The above example shows how a dispositional tendency like aggression may be reinforced early in life by the social environment and then becomes well established. But our inpidual tendencies are not necessarily determinants of your fate in life. For example, the studies about socialization experiences can help infants who are temperamentally shy to develop into people who are not shy: because social experiences can modify temperament, biology does not have to be destiny (Schmidt & Fox, 2002).

Moreover, I do not entirely deem that it is “nurture” that is solely responsible because personality is partially determined by nature, or biological heritage. The genes that a person inherited from their parents influence how their personality has unfolded. Although specific genes for personality have not yet been identified, psychologists have studied identical twins in an attempt to discover the extent to which personality is inherited. Because identical twins possess identical genes, they have the same genetic determinants of personality. Identical twins who grow up together in the same family have the same permissive or strict parents and similar life experiences. If the twins have similar personalities, it is impossible to identify the source of the similarity because they have not only the same genetic makeup but also similar life experiences.

In contrast, identical twins who are separated at birth and raised in different settings (perhaps because they are adopted by different families) share the same genetic material but often have very different life experiences. This means that even though they have quite similar genetic makeup, their life traits will not be similar because of the different environments they were exposed in.

If I were to become a twin, I would prefer to become a fraternal twin because my identity will be more defined compared to being identical. As a child, it could be quite disconcerting to be confused of somebody that you are not most of the time. This is because even though identical twins are similar in appearance and the environment they grew up in, there are still slightly different characteristic traits. By separating identical twins at birth and placing them in totally different environments, researchers have assessed the impact of environment unambiguously. There are a fair number of cases in which identical twins are put up for adoption at birth and are raised in substantially different environments. Such instances allow us to draw fairly confident conclusions about the relative contributions of genetics and environment.

Unfortunately, the data from identical twins raised in different environments are not always without bias. Adoption agencies typically take the characteristics (and wishes) of birth mothers into account when they place babies in adoptive homes. For instance, children tend to be placed with families of the same race and religion. Consequently, even when monozygotic twins are placed in different adoptive homes, there are often similarities in the two home environments. The consequence is that researchers can’t always unambiguously attribute differences in behavior to genetics or environment.

As personality develops over time, people refer to their experiences as children when they become adults. Factors such as the strictness or permissiveness of a child’s parents, the number of other children in the family, the extent to which parents and teachers demand a lot from a child, success or lack of success at making friends or getting and keeping a job, and even the culture in which a person is raised and lives as an adult are shapers of personality.

Because about half of the variation in people’s personalities is inherited from their parents and, thus, is basically fixed at birth, it comes as no surprise that personality is quite stable over periods of time ranging. However, this does not mean that personality cannot change; it means that personality is likely to change only over many years. Thus, the impact of any specific situation or crisis on a person’s personality is likely to be felt only if the situation continues for many years. An important outcome of this fact is that we should not expect to change any person’s personalities as the way they are.

As studies, as of the present time, could not answer the question which is more influential between nature and nurture, we should satisfy ourselves with the explanation that both have pivotal roles in developing our life traits as a whole person. Thus, it is safer to deem that virtually all traits, characteristics, and behaviors are the joint result of the combination and interaction of nature and nurture. Like love and marriage and horses and carriages, genetic and environmental factors work in tandem, creating the unique inpidual that each of us is and will become.

References

• Cary, W.R. (2004). Are We Hardwired? : The Role of Genes in Human Behavior. NC: Oxford University Press, Incorporated.
• Contrada, R. J., Leventhal, H., & O’Leary, A. (1990). “Personality and health”. In L. A. Pervin (Ed.). Handbook of Personality: Theory and Research (pp. 638-669). New York: Guilford.
• Dodge, K. A. (1986). A social information processing model of social competence in children. In M. Perlmutter (Ed.), The Minnesota Symposia on Child Psychology: Vol. 18. Cognitive Perspectives on Children’s Social and Behavioral Development (pp. 77-125). Hillsdale, NJ: Erlbaum.
• Petrill, S.A. & Wilkerson, B. (2000). “Intelligence and achievement: A behavioral genetic perspective”. Educational Psychology Review, 12, 185–199.
• Schmidt, L.A. & Fox, N.A. (2002). Inpidual Differences in childhood shyness: Origins, malleability, and developmental course. In D. Cervone & W. Mischel (Eds.), Advances in Personality Science. New York: The Guilford Press. (pp. 83-105).