“We have been very conditioned by the cultures we come from and are usually very identified with the particular gender we belong to.” This quote from Andrew Cohen explains in part how gender identity develops, through the conditioning of our environments. The most influential factor on gender development, however, is still a highly controversial issue. An analysis of the gender identification process reveals two main arguments about which factor contributes more to gender development: biological differences (nature) or environment (culture). The first major factor said to influence gender is biology. “Nature does not give a penny to our social theories, fads, political ideologies and other absurd ideas that people worry about (*). This quote explains the argument from the biology side. People who support this ideology believe that major biological differences between males and females must influence our gender development the most due to their numerous studies. One of the main biological differences between males and females is hormones. Hormones that were once thought to be important only for pregnancy and sexual desire have now been shown to have profound effects on nearly every organ in the body.(*) Some researchers believe that increased exposure to estrogen, in females, or to androgens, in males, during fetal development not only causes the formation of the sexual organs, but also predisposes the child to behaviors typically associated with one or the other gender. (*) For example, girls who had been exposed to higher-than-normal levels of androgens prenatally were more likely than other women to engage in "boyish" behavior and to play with boys' toys even... in the midst of paper. .....diferences-between-the-brains-of-men-and-women/5. Leo, J. (2000). The structure of the brain explains male/female differences. Male/female roles: opposing points of view (pp. 32-34). San Diego, CA: Greenhaven Press.6. Reese, C. (2000). Biological differences establish gender roles. Male/female roles: opposing points of view (pp. 18-19). San Diego, CA: Greenhaven Press.7. Rhode, D. (2000). Culture establishes gender roles. Male/female roles: opposing points of view (pages 22-24). San Diego, CA: Greenhaven Press8. Sabbatini, R. (n.d.). Are there differences between the brains of males and females? "Brain and Mind" magazine - Home Page WWW. Retrieved April 14, 2011, from http://www.cerebromente.org.br/n11/mente/eisntein/cerebro-homens.html9. Sagan, D. (2000). Hormones determine gender traits. Male/female roles: opposing points of view (pp. 42-43,46). San Diego, CA: Greenhaven Press.