The Debate Of Nature Vs. Nurture

One of the largest disagreements in behavioral science is the question of nature versus nurture. Dating back to Locke’s idea of Tabula Rasa, scientists have argued over the source of personality. The nature approach believes that personality is a result of our DNA; the nurture approach believes that our personality is shaped by our experiences. Those who support nature point to heritable mental illnesses, evolved behaviors, and common behaviors across generations as evidence for their side. The supporters of nurture, on the other hand, point to sexual orientation, studies of IQ, acquired mental illnesses, and difference in identical twins as evidence for their argument. Both sides have widespread support from the public, scientists, and research.
Those who support nurture argue the impossibility of a so-called “gay gene” due to the general lack of progeny. This view had been criticized for its dismissal of bisexuals and pansexuals, but remains valid, as “ . . . most gay men and lesbians have heterosexual parents . . .” [1]. Those who support nature point to the presence of homosexuality throughout various environments and cultures across the world. They state that despite the lack of similar environments and cultures, homosexuality is still observed; therefore, it must be genetic. They also cite the correlation between genetic similarity in siblings and their similarity in sexual orientation. Numerous studies (Kallmann, Diamon and Whitam, etc.) have shown a statistically significant correlation between genetic closeness and sexual orientation concordance. A recent study in the “Archives of Sexual Behavior” found that identical twins have concordant sexual orientations ~66% of the time, compared to fraternal twins’ ~30% [2]. This creates a dichotomy, because despite the fact that studies show an obvious genetic component to homosexuality, no gene has been identified, and a genetic cause is, at times, illogical. However, if one sees personality as a result of the environment’s interactions on our genes, this dichotomy is resolved. No gene codes for sexual orientation, but environmental conditions can interact with genes to cause homosexuality.
The so-called “grandmaster experiment”, conducted by Laszlo Polgar, is a convincing argument for environmental sources of intelligence. Starting in the 1970’s he raised three children according to his predesigned plan, in order to create prodigies. His three children became some of the most impressive chess players in history, with two of them becoming grandmasters. In 1989, he published his plan for raising geniuses in “Bring Up Genius!”, and firmly established environmental effects on intelligence [3]. More scientific studies have demonstrated the lack of evidence for a genetic component to IQ. A study in the APA shows the massive effects the environment can have on IQ, and points to the large changes in IQ between generations as proof against heritable intelligence [4]. Another source of evidence for nurture is the existence of feral children. When children develop isolated from language, society, and culture, their intelligence is irrevocably stunted. They are unable to learn more than simple language, and never gain understanding of social behaviors. Regardless of their genetic similarity to parents, feral children have little personality or intelligence. This points clearly to an environmental source of personality and intelligence, with no genetic input. Supporters of nature point to families with multiple generations of intelligent offspring, but despite some