When considering the biology of heredity, it is obvious that genes provide humans with their own physical equipment. 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. Twin studies are performed 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). 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. 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 1980s 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). 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 present an informative contrast… because 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 newer studies 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 seemed 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 granting 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. 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). The picture of Tom Green depicts that they way children are raise does not necessarily mean that they will grow up to be that way. I have watched “The Tom Green Show” numerous times and his parents are nothing like him. They are a very modest and shy couple, where as Tom is an outgoing and extremely cocky.
Through my own personal experience I have witnessed classic cases where environment has played a drastic role in the way people lead their lives. During my childhood days in Pennsylvania I had a friend who was adopted and had never met his biological parents. He grew up to be exactly like the people who raised him. He had the same personality, same political views, and the same outlook on life. However, I don’t know what his biological parents are like this seems to serve as reliable support for the nurture side of the argument.
However, when I moved to Minnesota a couple years ago I met a girl who was adopted and was nothing like the people who had raised her. She was on an entirely different level than they were. They opposed each other on almost everything. Her parents were diehard conservatives while she was extreme liberal. My mother also serves a unique example. She is drastically different from anyone in her immediate family.
Their personalities are like night and day. Both heredity and environment affect one considerably. 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. Psychology