- Cameron Mazzeo MSW, LCSW
The Human Spectrum: Science, Religion, and Culture Teach us About Gender
There’s a common misconception in popular culture that there’s only two sexes and two genders in humans. But science, and many religions, disagree.
The human brain isn’t exactly gendered. Most changes are based on brain size, not sex or gender. There’s maybe one characteristic with any significant gendered differences, but even those differences aren’t binary. There’s a section of the brain called the bed nucleus of the stria terminalis (BSTc), which has a variety of neurons that are based on gender identity, not sex. In transgender women, both pre and post HRT, the number of neurons in this section were far closer to cisgender women. The same went for transgender men and cisgender men.
Further studies show that gender has differentiated biological responses to specific stimuli is also mirrored by gender identity, not assigned gender at birth. But even that showed a spectrum of reactions – some women showed a reaction in-between the two sides of the male-female response spectrum. That isn’t exactly news, though. Biologists have acknowledged anywhere from 6 to 9 sexes in humans since as early as the 1930s. Hormones, chromosomes, brain structure, even genitals, have more than two variations each. When combined, there’s a wide range of sexes and genders humans can be.
Biology, and nature, are messy spectrums of traits, and do not fit neatly into boxes.
However, if the closest thing to “Brain Sex” that humans have aligns with Gender Identity more than Assigned Genders at Birth,
what does that mean for religious people? Well, many, many cultures and religions have more than two genders. Judaism has 6 distinct genders in its religious texts. There’s the māhū of Hawaii, the fafafine of Polynesia, the hijras of South Asia, and many others. If I listed them all, it would be longer than a regular blog post, so instead, I’ll just link the PBS map of cultures with more than 2 genders.
But presuming you’re a Conservative American Christian, and are looking for advice on how to handle transgender and nonbinary people? Well, perhaps reflect on Psalm 139:13-16, Matthew 7:1-3, Proverbs 6:16-19, and all of Leviticus 11 and 19. The word for Love is mentioned 686 times in the bible. Do some deep reflection of your feelings on transgender/nonbinary people, are these thoughts truly spiritual or are they your own thoughts and religion is just a shield your use to justify them.
Which is a long way of saying that acceptance and affirmation are the best practices. In science, religion, and morality, we are called to love and affirm one another and do the least harm to each other. But unless you are omniscient, the only way to know what helps or harms someone is by asking them, and overwhelmingly, the answer is affirming care, acceptance, and understanding.
Remember all the words and definitions we use are all cultural, and manmade. It takes some adjusting of your worldview to accept what reality creates. Which, granted, can take some work. Relearning old habits, and admitting ignorance or misunderstandings, is a big challenge. Human growth comes from challenge, so it’s an endeavor worth doing. For anyone, of any religion or belief, who is looking to learn some basic terminology, here’s a handy list of terms to add to your vocabulary.
Abrams, Mere. “64 Terms That Describe Gender Identity and Expression.” Healthline, 20 Dec. 2019, www.healthline.com/health/different-genders.
Bakker, Julie. “Brain Structure and Function in Gender Dysphoria.” Endocrine Abstracts, May 2018, https://doi.org/10.1530/endoabs.56.s30.3.
Berglund, H., et al. “Male-To-Female Transsexuals Show Sex-Atypical Hypothalamus
Activation When Smelling Odorous Steroids.” Cerebral Cortex, vol. 18, no. 8, Dec.
2007, pp. 1900–8, https://doi.org/10.1093/cercor/bhm216.
Claire Ainsworth, Nature magazine. “Sex Redefined: The Idea of 2 Sexes Is Overly Simplistic.” Scientific American, 22 Oct. 2018, www.scientificamerican.com/article/sex-redefined-the-idea-of-2-sexes-is-overly-simplistic1/.
Collins, MA, Donald. “What Is LGBTQ+ Conversion Therapy?” Psych Central, 14 June 2021,
Eliot, Lise, et al. “Dump the ‘Dimorphism’: Comprehensive Synthesis of Human Brain Studies Reveals Few Male-Female Differences beyond Size.” Neuroscience & Biobehavioral
Reviews, vol. 125, Feb. 2021, https://doi.org/10.1016/j.neubiorev.2021.02.026.
---. “You Don’t Have a ‘Male or Female Brain’: Studies Weaken Theories of Human Brain Sex Differences.” Neuroscience News, 24 Apr. 2021, neurosciencenews.com/male-female-brain-debunked-18276/.
Fox, Genevieve. “Meet the Neuroscientist Shattering the Myth of the Gendered Brain.” The Guardian, The Guardian, 24 Feb. 2019, www.theguardian.com/science/2019/feb/24/meet-the-neuroscientist-shattering-the-myth-of-the-gendered-brain-gina-rippon.
Garcia-Falgueras, A., and D. F. Swaab. “A Sex Difference in the Hypothalamic Uncinate
Nucleus: Relationship to Gender Identity.” Brain, vol. 131, no. 12, Nov. 2008, pp.
Hildreth, Cade. “The Gender Spectrum: A Scientist Explains Why Gender Isn’t Binary.” Cade Hildreth, 27 Apr. 2020, cadehildreth.com/gender-spectrum/.
Kennon, Joshua. “The 6 Most Common Biological Sexes in Humans.” Kennon-Green & Co, 7 June 2013, www.joshuakennon.com/the-six-common-biological-sexes-in-humans/.
Kruijver, Frank P. M., et al. “Male-To-Female Transsexuals Have Female Neuron Numbers in a Limbic Nucleus.” The Journal of Clinical Endocrinology & Metabolism, vol. 85, no. 5, May 2000, pp. 2034–41, https://doi.org/10.1210/jcem.85.5.6564.
Kurth, Florian, et al. “Brain Sex in Transgender Women Is Shifted towards Gender Identity.” Journal of Clinical Medicine, vol. 11, no. 6, Mar. 2022, p. 1582, https://doi.org/10.3390/jcm11061582.
Montañez, Amanda. “Visualizing Sex as a Spectrum.” Scientific American Blog Network, 29 Aug. 2017, blogs.scientificamerican.com/sa-visual/visualizing-sex-as-a-spectrum/.
PBS. “Interactive Map: Gender-Diverse Cultures.” Independent Lens, 11 Aug. 2015,
Testard-Vaillant, Philippe. “How Many Sexes Are There?” CNRS News, 1 Aug. 2016, news.cnrs.fr/articles/how-many-sexes-are-there.
Verrett, Bethany. “How Many Times Is Love Mentioned in the Bible?” Biblestudytools.com, 18 Mar. 2022, www.biblestudytools.com/bible-study/topical-studies/how-many-times-is-love-mentioned-in-the-bible.html.
WHEELING, KATE. “The Brains of Men and Women Aren’t Really That Different, Study
Finds.” Www.science.org, 30 Nov. 2015, www.science.org/content/article/brains-men-