In the United States, our conception of gender and the differences between men and women have deep traditional roots. Men are expected to be strong individuals who support and defend their families. Women are seen as caring and motherly, gentler and tamer. We believe so much that the two genders are totally distinct, with such different traits, that it almost seems as if men and women are born with different qualities. But is this really the case? Are girls really born with the genes that allow them to prefer pink dolls and Barbies, while boys are genetically predisposed to behave like warriors and defend their family? Are masculine and feminine simply genetic facts? The evidence seems to support a deeper reason than that. As a culture, we have developed and defined these gender roles over centuries. We've determined what fits men and women, and anything that doesn't fit those molds is ostracized. The traits that we deem so important for men and women are so ingrained in our society that they seem natural. But maybe they aren't. Not all societies operate like ours. There are societies with a distinctive third gender, such as the Hijra in India and the Kathoey in Thailand. If these "third genders" are acceptable and normal in other cultures, it seems unlikely that gender is biologically determined. Instead, gender learning is a social practice that begins before a child is even born. When parents paint their child's nursery pink or blue, they are already reinforcing the same social customs and gender rules that they were taught as children. There are some biological differences between the male and female brain. But these differences do not take into account our strict concepts of gender...... middle of article ......es, evolution and gender. Flight. 6, no. 1 (April 2004) pp. 45-53. Lucal, Betsy. “What It Means to Be Gendered: Life on the Boundaries of a Dichotomous “Gender System.” » Gender and society. Vol 13., No. 6 (December 1999) pp. 781-797. McCabe, Allyssa. “Developmental psychology”. Access the science. McGraw-Hill Enterprises, 2008. Reddy, Gayatri. “Men” who wanted to become kings: celibacy, emasculation and the reproduction of Hijras in contemporary Indian politics. Social research. Flight. 70, No. 1. (2003). pp. 163-200. Turner, Stephanie. “Intersex Identities: Locating New Intersections of Sex and Gender.” » Gender and society. Vol 13, No. 4 (August 1999) pp. 457-479. Winter, Sam. “Thai Transgender Focus: Demographics, Transitions, and Identities.” » International Journal of Transgenderism, Vol. 9, No. 1 (2006). pp. 15-27.