Genetic and environmental influences on human development

¶ … nature vs. nurture theory. The author uses two books to draw information supporting the arguments presented in the paper. There were four sources used to complete this paper.

For many years experts in the fields of biology, physics and chemistry have argued the elements of nature vs. nurture. Experts have remained divided on what drives a person to do, think, act and feel the way he or she does.

Those who believe in the nurture theory argue that it is in the raising of the child and the lessons he or she is taught that ultimately shapes the end result. Those who favor the nature side of the argument disagree, and believe that the genetic component is much more important than anyone realizes when it comes to the eventual adult creation.

Two experts in the field of science when it comes to human nature believe that nature is the underlying driving force behind the design of people.

Steven Pinker in The Blank Slate: The Modern Denial of Human Nature puts together a blueprint pathway to explain how human nature is indeed driven by nature, or long-term genetic components.

Stephen Jay Gould presents similar ideas in many of his works as well. The argument of nature vs. nurture continues to rage while mankind continues to make scientific discoveries that support the genetic elements of mankind's evolutionary nature.

There have been many evidences that nature has a stronghold on the creation of a person's basic character and patterns, including studies on identical twins who were separated as infants and raised in different homes.

The twins end up becoming adults with striking similarities when it comes to temperament, personality and likes and dislikes. These studies along with other aspects of study indicate that nature is much more ingrained in "who we are" than previously believed.

The Side for Nurture

Those who believe that the nurturing of a human casts the ultimate decision on how that person will react and interact as an adult believe that the mind is a blank slate when a person is born.

The advocates of such theories think that a baby has a blank mind. He or she is born knowing nothing and not having any preconceived urges, ideas or desires. According to the experts who subscribe to such theories the baby's mind and consequently his or her emotions are then shaped by the things that he or she is taught during upbringing.

This theory has often been brought up in courtrooms of people accused of violent crimes (Pinker, 2003). Ted Bundy, Jeffery Dahmer and others have tried to use the defense that they were abused during their formative years, which in turn created the mindset that allowed them to go out and commit heinous acts of violence against their fellow human beings. Cases such as the Menedez boys, who were convicted of killing their father, used the same defense.

According to their defense attorneys, the boys were taught violence at home by a brutally controlling father, and therefore should not be held responsible for the actions that killed their father.

For many years the debate over nature vs. nurture has dominated such cases. There are many other life areas in which it appears as well. IQ testing, disorders such as ADHD and depression and other points of interest to the scientific community have all studied the debate about nature and nurture to see if there is a cause and effect relationship in raising a child and just bearing a child with certain predisposed genetic traits.

Currently the school of thought on the nature side of the argument is that humans are not born with a blank slate for brains and emotions, but are instead born with a pre-calculated set of genes which drive that person to react in certain manners as life unfolds.

NATURE BEATS OUT NURTURE

Steven Pinker, who is well-known as a professor at MIT faces the debate head on in his book. In it he attacks the idea that humans are born with a blank slate for a mind. In his opinion there have been many years of genetic programming that has been handled by nature. Pinker details his theory, while at the same time dismantling the theory of the blank slate that has prevailed for so many years. While the blank slate is easier to handle on an emotional level, it is important to know whether or not it is a valid measurement of human nature for future study and need (Pinker, 2003).

THREE THEORIES

The Blank Slate premise holds that humans are born with no ability to think, reason, feel or react at all. It holds that people are completely shaped by their experiences in life and those experiences determine what type of person they become. This theory is one of those that believe nurturing creates the human (Pinker, 2003).

Another theory that has been used for years is the Noble Savage theory. Pinker outlines it as believing every person is born good and pure and society corrupts the person as they grow. This is the attitude and belief of many serial killer defenses. The people who use the society ruined them theory try and convince juries with stories of abusive childhoods, being attacked and shunned by society and other incidences to blame the eventual outcome on rather than blame the person who did the crime.

The third theory that is often used to explain the way human beings think and react according to Pinker is a Ghost in the Machine theory. This theory holds that every person is born with a soul and that the person makes choices from that soul. The theory believes that biology has nothing to do with the decision making process (Pinker, 2003).

For one to understand how nature impacts the thought process one has to have a grasp of the sciences. Behavioral genetics, Evolutionary sciences and cognitive sciences work together to connect culture and biology. The evolutionary process is perhaps the strongest explaination about how humans become and form their brains, thoughts, emotions and internal reactions. Evolutionary processes dictate that mankind has gone through changes over the years that have been dependent on need.

This can be underscored by looking at the results of IQ tests and the periodic "re-norming" of them. Intelligence Quotent testing has a medium score to hit the average mark and then for every 15 points on either side of that it is a standard deviation. This system is used to determine one's intelligence. This testing system is renormed every so often as mankind continues to evolve and score better than past generations did on the testing system.

This is one example of how the evolutionary process creates genetic predisposition to the eventual person.

Another strong indicator of the evolutionary importance in human nature is a look at families. Many families have multiple children as siblings. Siblings are often raised with the same rules and morals. Families have set expectations for the children and they are often applied across the board for each one. This would seem that all children would grow up making the same type of choices and having the same morals and values but this is not the case (Pinker, 2003). There are many instances in which the siblings of the same family grow up having completely different values and morals and actions in their lives. The serial killers of the world often have siblings who lead quiet and productive lives as their siblings embark on killing sprees.

To date, several studies have indicated that there are brain receptors and other biological factors involved in the human blueprint.

The nature-versus-nurture debate over anxiety is not a new one. The fact that such changes take place at the receptor level does not necessarily indicate that nature has won out over nurture (Behavior, 2002)."

In order to investigate the relationships between interactions and moral-reasoning development, Walker, Henning, and Krettenauer (2000) recorded a series of conversations between teens (boys and girls ages thirteen to sixteen) and a parent, as well as between teens and a friend. The conversations contained both hypothetical moral dilemmas (to allow for comparison between participants) and actual moral dilemmas. The latter were situations reported by the participants, involving themselves (to allow for comparison across contexts). In addition, each participant's stage of moral-reasoning development was rated annually, using a standard process (Colby & Kohlberg, 1987), so that an investigation of moral growth could extend over a four-year period. The results of the study revealed different types of interactions with peers and parents that could be used as predictors of growth in moral reasoning. Three main areas of insight relevant to summer camp are: types of moral-dilemma discussions, types of interactions, and relationships of interactions to moral-reasoning growth (Powell, 2001). "

Stephen Jay Gould also works to prove that nature through the evolutionary process is a strong factor in the development of human beings. According to Gould, Darwin has been misconstrued and misunderstood (Gould, 2002).

Gould believes that science and religion can and should co-exist peacefully. The belief that nature is evolutionary and gradual fits with Gould's belief about science and religion.

CONCLUSION

The debate about nature vs. nurture has raged on for many years. The more society learns about science the more it learns that nature has a significant impact on the shaping and development of a person. This is important because it will change the way law enforcement agencies, educators and others plan for the future. Rehabilitation, preparation for students and other things will be looked at from a different angle once it becomes accepted that nature and genetics through an evolutionary process provide the cornerstone for development of the shaping of people.