Biological Homosexuality

Homosexuality is at the front lines of the nature versus nurture debate. Many studies have been conducted, but a clear cause has yet to be found. Anti-homosexuals, consisting mainly of religious groups, believe that homosexuality is abnormal, unnatural, and can be changed. Because of their beliefs, homosexuality must be a learned behavior. Whether homosexuality is biological or learned behavior is still a mystery, but scientists are finding more evidence to suggest the former.
Webster’s online dictionary defines abnormal as deviating from the normal or average. By that definition alone homosexuality is abnormal, but there are other things that are “abnormal” which are acceptable in today’s society. According to the 2000 United States Census Bureau report, 75.1 percent of Americans are Caucasian. So it is logical to assume the “average” American is Caucasian, but not being Caucasian is not considered abnormal. Minorities have genetic traits that make them different, and it is impossible to change these genetic traits. The same concept holds true for homosexuals. Homosexuals are a minority because they are biologically different from the majority. So what makes them different? Studies show there is clear a difference between the brains of homosexuals and heterosexuals, and part of it lies within the hypothalamus. The hypothalamus is a small part of the brain that controls sexual behavior, among other things, and it responds to pheromones (Hypothalamus, n.d.). Several nuclei in the hypothalamus are sexually dimorphic; this includes the interstitial nucleus of the anterior hypothalamus (INAH). The INAH is a nucleus located between the groups of tissue in the anterior hypothalamus. Although there are four INAH, only the INAH3 is widely accepted as sexually dimorphic (LeVay, 1991).