"Biological determination" is a term used in some sociological and feminist literature to describe the belief that human behavior is controlled by an individual's genes.
Biologists and evolutionary psychologists generally regard a charge of biological determinism as a straw man, as there is currently no support for strict biological determinism in the field of genetics or development, and virtually no support among geneticists for a strong thesis of biological determinism. Biological determinism plays a role, and has played, a role in general opinion and public notions which influences the concepts of race and gender.
Lynda Birke's In Pursuit of Difference outlines areas of human biology that present "clear-cut differences" between genders with regards to chromosomes, genetics, and inheritance. Obvious physical differences between males and females emerge during puberty, but hormonal differences are "not absolute". There is a broad range of reproductive anatomy that doesn't necessarily fit the "gender definition" of male or female. According to the Intersex Society of North America, "a person may be born with mosaic genetics", differing in their chromosomal configuration. The website is helpful in answering questions regarding anatomical variations of sex/gender and discusses the ways in which nature presents us with "sex anatomy spectrums". There is more to one's sexual assignments then a male/female division. Biologically and physically, there are apparent differences that point to one's intersexuality.
Though scientists are unsure as to whether homosexuality can be attributed to biological or social factors, many LGBT rights activists have used the theories of biological determinism to support their cause. This has become a frequent point of dissension between pro-gay individuals and anti-gay individuals. Because a single cause has not been determined as the cause of homosexuality, many scientists theorize that a combination of biological and social determine one's sexual orientation. Gay rights advocates believe that proving that homosexuality has a definite biological basis will prove it to be an unchangeable characteristic, thus allowing homosexuals to be protected under the Fourteenth Amendment. One area of research that has been a valuable tool for gay rights activists has been Dean Hamer's work studying the "gay gene". Another researcher who worked with Hamer in finding evidence for biological influence in male homosexuality was Simon LeVay, a neuroscientist. In 1991, LeVay published an article in Science Magazine that detailed the difference in hypothalamic structures between homosexual and heterosexual men. His findings in studying the INAH-3 implied that "sexual orientation has a biological substrate." Though his research showed that there was a biological basis in sexual orientation, LeVay cautioned against people interpreting his article to say that he found that homosexuality is genetic, emphasizing that he had not "locate a gay center in the brain-- [as] INAH3 is less likely to be the sole gay nucleus of the brain than part of a chain of nuclei engaged in men and women's sexual behavior." He merely hoped that his work would serve as a catalyst in working towards finding more evidence that homosexuality is genetic.
In modern society, people with racist notions often use the aspects of biological determinism to justify their beliefs that people of different races are separated by ability and predisposition. This linking of one's race with inferiority has been prevalent in society for centuries and has lead to slavery, war, and racial segregation. Nina Jablonski, a professor of anthropology at Pennsylvania State University, notes that while many people assert that race is a social construct, racist beliefs that one's skin color is somehow associated with one's moral, social, and intellectual characteristics still persist to this day. And although there have been countless studies that provide genetic evidence that races are nonexistent, the belief that one's race makes one innately superior over another endures as an unavoidable influence in today's world. These notions of ingrained superiority lie in the belief of a particular hierarchy of skin color. Deep-rooted racism appears to be based on the belief that differences in people's intellectual capabilities, moral values, and behavioral proclivity are somehow analogous to one’s skin color. This enduring belief of predisposition based on race can be attributed to the acceptance of biological determinism and the use of biological deterministic values to determine a “natural” social order. Racism that stems from the belief of biological determinism appears to be detrimental to both parties, according to Jablonski. For the person with the racist ideals, it often plants the idea into their head that their own race is inarguably superior in every aspect and for the race being targeted, it puts into their mind the idea that they are somehow inferior, weaker, or stupider. This categorization “becomes determinative of personality and individual experience, and is itself a destination.
Many people with extreme sexist beliefs often attribute the inferiority of a particular sex to that sex's biology. Though this is not always the case, the components of biological determinism are often used by those who who hold sexist beliefs against women. In terms of academia, the assumption that women's supposedly inferior abilities in math and science can in any way be attributed to their biology has been challenged on several different occasions. Richard Lewontin, an American evolutionary biologist who worked closely with Steven Rose and Leon Kamin, wrote the 1984 book Not in Our Genes which explored just how biological determinism worked in the scientific and academic realm. As Lewontin notes, this challenged belief’s basis is the “evidence” that demonstrates that men statistically have larger brains, are stronger, are more likely to hold higher positions in the work place, and are recognized more often for their academic contributions, etc. Lewontin goes on to state that these statements for the most part go undisputed and are viewed as being dependent on “underlying biological differences between males and females at the level of brain structure. In "NINETEENTH-CENTURY CRANIOLOGY: THE STUDY OF THE FEMALE SKULL", Elizabeth Fee, a historian of health and medicine discusses what many anthropologists of the 1860s viewed as a "social problem". In a time where the women's rights movement was viewed as a legitimate hazard, several anthropologists of the Anthropological Society set out to use their scientific educational background and positions to undermine the advocates of gender equality in the educational and scientific realm. One of the main reasons behind this was that many anthropologists believed that women were assigned a specific role in nature and that they were never to stray from that set role. This role was motherhood, to which all women were "biologically destined." The Anthropological Society emphasized that women were to wholly accept and embrace this role because motherhood was seen as completely "incompatible with intellectual pretension, economic competition, or the vote."
Some are born with the genitals of one particular sex, but hormonal and chromosomal differences may occur, causing one to be female on the outside, and male on the inside. Some females possess large amounts of male hormones (androgens), contributing to their more "masculine" traits. Sex chromosomes can vary. Occurrences like these are what arouse speculation regarding gender and the spectrum. Many speculate the physical and biological differences that point to a specific gender category, however, "humans decide whether a person with XXY chromosomes or XY chromosomes and androgen insensitivity will count as intersex."
Richard Lewontin, Steven Rose, and Leon Kamin were all interested in the way that biological determinism was present in science. They wanted to figure out how much of it was true, and how much of it was socially constructed according to certain beliefs and societal norms and determined gender roles within society. In their book Not in Our Genes they explore the possibilities of biological determinism. In their studies, they found some very interesting evidence that points to the fact that biological determinism in science is actually greatly affected by certain norms and tendencies within society. One of the big issues with this is that biological determinists tend to look for support for their own claims within science and nature itself. According to them, biological determinism is more constructed by society that by anything else. In a study that was performed on girls who were more “masculinized” than others, biological determinists John Money and Anke Ehrhardt looked for ways to describe femininity that fit into the common definition of it, such as clothing preference, using makeup, etc. Although these scientists believed that they were providing evidence to support their definitions of femininity within nature, they fell into the trap of labeling these girls according to Western social standards. As Lewontin points out, this experiment not only embraces the stereotypes that already existed, but it also “ignores the existence of societies in which women wear pants, or in which men wear skirts, or in which men enjoy and appropriate jewelry to themselves.” Lewontin, Rose, and Kamin realize that biological determinism is clouded and, can in fact, be shaped according to the standards and norms of the society one lives in. Therefore, they choose to take a different approach. They decide to look at numbers and statistics instead of simple social experiments which can be easily misinterpreted. When they look at the numbers and statistics of men and women over the years, they discover that the differences between men and women are no longer as pronounced as they had been in the past. All of a sudden, there are more women in the work place holding higher ranking jobs. More women are excelling in areas that used to be male dominant, such as sports. And even biologically, women are beginning to catch up to men in height and life expectancy. However, these changes are mostly visible in numbers and statistics. In reality, social differences between men and women are still easily observed. Lewontin, Rose, and Kamin argue, however, that these differences are actually imposed by society itself.
The standard model for the difference between sex/gender states that there is a clear-cut dichotomy between males & females, with no overlap. Because of this norm, we have a historically constructed viewpoint of “average”, meaning that society holds the idea that one must be either male or female, feminine or masculine. Anne Fausto-Sterling's article “Of Gender and Genitals” discusses how this standard model shapes doctors’ ideas about gender and what is socially acceptable. She claims that(according to the standard model) “Bodies in the "normal" range are culturally intelligible as males or females, but the rules for living as male or female are strict”, meaning that we are culturally “trained” in believing that there is a sexual binary and anything outside of those confines is rejected.
The Pipeline and Children's toys
As Londa Schiebinger in "Has Feminism Changed Science?" describes the existing gender issue of the pipeline, in which "if more girls entered the educational end of the pipeline, more women would be turned into credentialed specialists and empty into the science job pool". Simply put, a much higher percentage of women need to be placed in the science and mathematical fields to produce an end result of a couple females who persisted and attained their Ph. D's in their male dominated fields. As for men, the amount of men who pursue within the scientific field, most likely carry through and a higher percent of males attain their professional degrees. Males outnumber females in scientific and mathematical realms due to their gender assignment. Schiebinger elaborates, "Factors that will lead girls to reject science as a career are thought to be cultivated very early-even moments after birth. In one study, parents were asked to describe their newborn babies-at a time when one of the few things they knew about the child was its sex." Parents described their male offspring as adventurous and observatory, as for female offspring, they were noted to be more fragile. Parents encourage their boys to conquer, enlighten, and provide the boost of ego to be successful within the scientific field. Simultaneously, parents treatment towards their female child carries the responsibility of teaching them homemaking skills and to abstain from "rough-and-tough play". Schiebinger notes, "adults tend to give children toys that reinforce sexual stereotypes". Girls are given dolls and encouraged to voice out their emotions, while boys play with cars and balls. Society has molded the norm for children to have distinct modes of play and interaction, which leads to advertisements and manufacturers who "insist that toys be clearly gendered". Handing a toy to a child, depending on their gender may seem harmless at their young age, yet "toys create aspirations, hone conceptual skills, and encourage certain behaviors to the exclusion of others." 
- Feminist Frontiers, Ninth Edition, by Taylor, Whittier, and Rupp; How Societies Work, Fourth Edition, by Joanne Naiman
- Nature via Nurture by Matt Ridley, 2003
- Lederman, Muriel (2001). The Gender and Science Reader. London: Routledge. p. 323.
- In Pursuit of Difference by Lynda Birke, 1992
- Intersex Society of North America
- Paul R. Abramson, ed. (1995). Sexual Nature/Sexual Culture (1 ed.). University Of Chicago Press. p. 4. ISBN 0226001822.
- Brookey, Robert Alan (2001). Argumentation and Advocacy 37.
- Spanier, Bonnie (1995). NWSA Journal 7 (1): 54.
- Nimmons, David (March 1994). "Sex and the Brain". Discover Magazine.
- Jablonski, Nina (September 2012). "The Struggle to overcome Racism". New Scientist 215 (2880): 26–29.
- Lewontin, Richard; Steven Rose, Leon Kamin (1984). Not in our Genes. Pantheon Books. p. 132.
- Fee, Elizabeth (1979). "Nineteenth Century Craniology-The Study of the Female Skull". Bulletin of the HIstory of Medicine (The Johns Hopkins University Press) 53: 417.
- Lewontin, Richard, Steven Rose, and Leon Kamin. Not in Our Genes: Biology, Ideology and Human Nature. New York: Pantheon Books, 1984. “The Determined Patriarchy,” Chapter 6, pp. 131–163
- Fausto-Sterling, Anne in "Of Gender and Genitals", 2000
- Schiebinger, Londa in "Has Feminism Changed Science?", 1999