Nature Vs. Nurture in Sociology

Influences on Personality, IQ and Homosexuality

The nature vs. nurture debate is a longstanding discussion regarding the effects of biology and social systems on individuals and behavior. Proponents of the “nature” side of the debate argue that people are shaped primarily by genetics and biology. The “nurture” side argues that our environmental influences and socialization are the most important factors in determining who we are and how we behave.

The "nurture" theory states that people are a tabula rasa or blank slate, and behavioral traits are developed rather than innate.

Nature vs. Nurture and IQ

Evidence suggests that the family environment can affect up to a quarter of the variation in childhood IQ. However, by late adolescence this correlation disappears and adopted siblings are no more similar in IQ than strangers are. In addition, adoption studies show that by the time adopted siblings become adults, they are no more similar in IQ than strangers with a correlation near zero, while biological siblings show an IQ correlation of 0.6. Studies of twins back up this pattern: Identical twins raised separately have a higher chance of similar IQs that fraternal twins raised together. Thus nature appears to be more important than nurture in explaining the variations in IQ.

Keep in mind thought that looking at intelligence as a trait also requires a definition of what that element is.

In looking at whether intelligence can be inherited, it's also necessary to define exactly what constitutes intelligence.

Nature vs. Nurture and Personality

Personality is often studied as a heritable trait in twins and adopted children. Identical twins raised in apart in different families are much more similar in personality than strangers selected randomly.

In addition, identical twins display more similarities than fraternal twins, and biological brothers and sisters are more similar in personality than adopted ones.

While this suggests that personality can be inherited, these same studies also allow for examining the environment as well as genes. Surprisingly, some adoption studies have found that by adulthood the personalities of adopted siblings in the same family are no more similar than those of strangers, indicating that the family's impact on personality dissipates by adulthood. Environmental effects that are not shared are often found to outweigh shared environmental effects, meaning that influences that are thought to shape people's personality, like family life, have less of an impact that environmental effects that aren't shared (factors which are difficult to identify).

Nature vs. Nurture and Homosexuality

Homosexuality is considered a genetic result rather than a development that's influenced by the environment. This is based on the findings that:

  • Approximately 10 percent of the global population identifies as gay. This number is consistent across cultures all around the world. If societies and various cultures and ways of living impacted the prevalence of homosexuality, the percentage of the population that is gay would vary around the world.
  • Studies of identical twins indicate that if one sibling is gay, there's a 50 percent or higher chance that another sibling is also gay.
  • Additional studies also show that gender and sexuality exist on a spectrum and represent more than just two options.