The nature versus nurture debate has been a classic controversy among experts for centuries. Presently, there is no clear conclusion to the dispute; yet, there are many hypotheses. Both sides of this controversy have been explored thoroughly among researchers. The purpose of this paper is to prove that the mental aptitude of a person is determined by his genetics, along with his environment, which affects it more. The nature side of the debate argues that a person maintains his mental ability only based on what he is born with genetically. Defending this side of the debate exclusively would be establishing that a person’s environment plays no role in determining his mental aptitude.
There are some reasons for an individual to be convinced that genetics play a large part in a person’s intelligence. When considering the biology of heredity, it is obvious that genes provide humans with their own physical equipment, which is in essence, their basis. Genes and chromosomes are passed on from each generation to the next. Therefore, without heredity, humans would have nothing to hand down biologically to their descendants; and this idea of genetics being purposeless is clearly incorrect. Twin studies are rendered on sets of twins; these include both identical twins and fraternal twins. They are conducted to determine the comparative influence of heritability and environment (Morris and Maisto 82).” These studies determine the heritability of a trait: to what extent the differences among individuals are due to genes, rather than to environmental factors such as upbringing, nutrition, and schooling” (Wright).
“Recent twin research showed that the genetic contribution to happiness and stability are about 50% and 80%, respectively, while life events have only a transitory effect on happiness” (Segal 55). Segal’s conception is not directly concerning human intelligence; yet, if his statement is in fact true, it substantiates some importance of heredity convincingly. It indicates that heredity certainly does have a notable effect on a person. In general, twin studies support the nature side of the debate (Morris and Maisto 82). Adoption studies are somewhat similar to twin studies because they are conducted for related reasons. These studies consist of monitoring and testing children who are adopted.
For them, researchers study the IQs in children, their birth parents, and their adoptive parents. These studies also partially support the nurture side of the debate. Some of these studies have shown that heritability is about 48% influential in most humans (Hamer and Copeland 219). Conversely, many investigations have shown that a person’s environment plays a large role in his mental aptitude. This may be the less obvious influential factor on one’s life. Though, considering the enormous result of a human’s surroundings and environment on his life, an in depth investigation should be taken examining this notion.
The amount of nourishment an individual receives has been proven to play a very large part in a person’s mental ability. This is especially true concerning infants and young children. The human brain critically needs nutritious food and antitoxins to function properly, particularly in early years of development. Starving people across the globe show why lack of nutrients in human bodies can stunt mental evolution as well as physical growth.
“What a premature infant eats in the first month of life can have lasting intellectual impact… a new study finds” (Raloff). A study done in Great Britain in the late 1980 s shows that nutrition plays a very large role in a person’s development. Adolescents aged twelve to thirteen were given vitamin and mineral supplements for eight months.
These subjects were then administered intelligence tests. Test scores were recorded before the test and after the test. These scores were also compared to other adolescents who were not given the supplements. The scores showed that the students who had taken the supplements scored higher on the tests after taking the supplements (Herrnstein and Murray 292).
A person’s environment also plays an important role on his development from early on. Much research shows that people flourish from early stimulation. In an experiment done by H. M. Skeels using orphans, he proved this conception. Skeels studied mentally retarded orphans.
Once these children were placed with families to live, were treated well, and were encouragingly nurtured, their IQs increased remarkably (Hamer and Copeland 221). Kagan and Havermann define operant conditioning as the process by which, through learning, free operant behavior becomes attached to a specific stimulus (578). John Watson conducted a substantial experiment in 1913 concerning behaviorism. He has become well- known as the psychologist who played a large role in the research of behaviorism, which is a division of operant conditioning. Watson used an 11-month-old boy to prove that a person could be conditioned to be afraid of something by which he was not previously affected. The baby used, Albert, was put into a room with no other human and no other distract ers present.
Watson placed a white rat in the room. Albert seemed to like the rat; he even showed affection towards it. Some time later, Watson would produce a very loud and displeasing noise every time Albert would reach out to touch the rat. As a result, the baby became terrified of every white and furry object in which he came in contact. This distinguished investigation became known as the “Albert experiment” (Kagan and Havemann 94). This established that humans could be taught certain feelings and fears through their environment, with which they were not born (Morris and Maisto 15).
Experiments such as these ones prove that a person’s environment can have a crucial effect on him and on his manner of thinking. Much research followed experiments like Watson’s. Psychologists have always been enticed by factors, namely environment, that affect humans. Adoption studies have also somewhat shown that a person’s environment plays an important role in his mental ability.
For example, a study done with adoptive children raised in the same house had very similar IQs. Granted this does not seem like considerable evidence; however, these children were in no way related genetically. Their environment growing up provided them with similar aptitudes for learning and for retaining information (Kagan and Havemann 39). “Fraternal twins (who share approximately half of their genes) present an informative contrast… (B) e cause they are raised in the same environment but are not genetically identical, they help us to see the influence of environmental factors” (Segal 69). These factors are valuable to this argument.
Although certain twin studies are not completely clear in their findings, one specific study indicates that some children’s environments have had significant influence on them. Much current research examines influences on intelligence. (Researchers) examine the extent to which children’s surroundings influence their intellect. In a prior study, they found that children adopted before age 1 into high-income families displayed particularly large IQ gains by adolescence. The new (er) stud (is) expanded on that (conception) (Bower 54-55). One study that was conducted proves that an individual’s environment can have an extraordinary affect on a person.
The subject of the investigation was called the “Wild Boy of Aveyron” (Herrnstein and Murray 410). He was discovered in France around 1799, which was soon after the French Revolution. The 12- or 13-year old boy had been found running naked in the woods, mute, wild, and evidently out of contact with humanity for most of his life… (He) seem (ed) to be unable to become fully human despite heroic efforts to restore (his) society (after the Revolution)…
From (this) rare case, we can draw a hopeful conclusion: If the ordinary human environment is so essential for bestowing human intelligence, we should be able to create extraordinary environments to raise it further (Herrnstein and Murray 410). Though exceptional, this incident shows that environment can have an extremely drastic influence on a person. Considering the evidence stated previously in this paper, it would be a result of ignorance to believe that one sole factor, either genetics or environment, determines a person’s mental ability. It is rather obvious that both of these factors contribute to a person’s mental aptitude. Through the research I have done, it seems that heredity, as well as environment, plays an important role in humans’ mentality; but these are not exactly equal in influence though.
A person’s entire environment seems to be more effectual in determining his mental ability than heredity is. The most fundamental way to rationalize my opinion is quite comprehensible. It is that heredity determines one’s potential, but environment devises how far one will reach that potential. “Nature designs blueprints and nurture modifies them each step of the way” (Dempsey and Zimbardo 164). ” (For instance), some genes increase our risk of heart disease: but if we know this and eat less fat, we reduce the risk” (Tudge).
A study was done to determine whether children who are born first are more intelligent than their later-born siblings. It primarily concluded that there is no relationship between a person’s intelligence and his time of birth. Mainly though, the study confirmed that both heredity and environment are influential in a person. “Intelligence is influenced by… genetics and quality of childbearing…
Parenting efforts can make all the difference in a child’s development” (Rogers 20). In certain cases, both heredity and environment could possibly play a roughly equal role in humans. The mental disorder schizophrenia is one of these circumstances. Schizophrenia has been proven to be very hereditary; furthermore, it is most common among people living in the poor rundown areas (Kagan and Havermann 39). Hence, humans with schizophrenia may have this brain disorder for a number of reasons related to both heredity and environment.
.”.. Because of our genes, we have our limitations… .” (Tudge). This is also an important fact to explore connected with human mentality. “Heredity sets limitations and tendencies while environment takes over to encourage or discourage the development and operation of our inborn traits” (Kagan and Havermann 40). Moreover, this debate is by no means completely resolved (Dempsey and Zimbardo 164).
Both heredity and environment affect one considerably; although, my research favors environment as having more influence on an individual. This debate, like most, is very inconclusive and ongoing. It is up to each individual to choose where he stands in debates like these. The mental abilities of humans are determined by an individual’s genetics. There is also substantial proof that an individual’s environment affects his mental aptitude. Through my research, I have come to the conclusion that environment is more influential, considering the great amount of evidence for that position.
What factor, genetics or environment, makes you think the way you do? Works Cited Bower, B. “Kids adopted late reap IQ increases.” Science News 24 July 1999: 54. Dempsey, David, and Philip G. Zimbardo.
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Raloff, J. “Preemie Diets Linked to IQ.” Science News 5 December 1998: 358. Health Source Plus. EBSCO Publishing. CCAC North Campus Library, Pittsburgh, PA.
14 November 2000.