For the vast majority of people it is difficult to see the social influence on biological sex. But there is greater variety associated with sex characteristics than can be accommodated by
simply looking at genitalia, and the decision to use that method to record sex on a birth certificate and then to insist that such a record defines someone for the rest of their life is certainly contestable.
One complicating factor is that external genitalia are not the only sex characteristics. There are chromosomes, hormones, internal reproductive organs and secondary sex characteristics. Do these attributes always tie up neatly into a gender binary? Fine warns against a simplistic approach to the effect of the genetic and hormonal components of sex on the reproductive system, “even
that developmental process [has been] described by one expert as a ‘balance’ rather than a binary system”.
20 The article Fine refers to includes an account of a 70 year old man, the father of four children, having a routine hernia operation and discovering that he had a womb. Arthur Arnold, who studies sex differences at the University of California, Los Angeles says: “The main problem with a strong dichotomy [between male and female] is that there are intermediate cases that push the limits and ask us to figure out exactly where the dividing line is between males and females. And that is often a very difficult problem, because sex can be defined in a number of ways”.
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Commenting on how sex should be defined when different characteristics clash, Eric Vilain, director of the Center for Gender-Based Biology at UCLA, says: “My feeling is that since there is not one biological parameter that takes over every other parameter…gender identity seems to be the most reasonable parameter.” In other words, concludes the author, if you want to know what gender someone is, just ask.
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