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  • Kim

Sex, Gender & Pride Month

Among the many wonderful professors I’ve had the privilege and opportunity to learn from, there is Dr. Max Krasnow. Due to my interest in a vast variety of topics, it is more difficult to find one person that can answer most of my never-ending questions, but thanks to his knowledge in a vast variety of topics he is the source of wisdom I often refer to when I need accurate, informative, and scientific information.

As someone who considers herself an ally for LGBTQ+ community I wanted to write a post about the topic, especially during this pride month but soon I realized that unfortunately I knew very little about the topic. Since Sex, Gender, and Evolution is among the several classes that Professor Krasnow teaches at Harvard, I reached out to him to find out more about Sexual Orientation and Gender Identity.

Here is the beautifully written reply I received from Dr. Krasnow and I am sharing it with his permission:

This pride month it feels topical to reshare what the science on sex/gender actually says (in contrast to how many people think and talk about it). When you hear the phrase 'biological sex' you probably have an intuition of what that means. But do you actually know?

Only some species reproduce sexually (2 parents mixing genes, as opposed to cloning), and only some of these are sexually dimorphic (the gametes they produce come in two types, larger eggs and smaller sperm, where sexual reproduction with gametes of the same morph is unsuccessful). This difference in the initial investment of resources is the abstract concept of 'biological sex' for a sexually dimorphic, sexually reproducing species. But how does that translate into how anyone should think about their own 'sex' or that of anyone else?

The mechanisms of typical sex determination in a species (how an offspring comes to produce one gamete morph or the other) vary wildly. In some species of reptile, for instance, sex is determined by the temperature of the environment that eggs experience. In some species of fish sex is socially determined, with the young developing as one sex and sometimes shifting to the other sex depending on the social environment they experience (e.g., if they are the largest individual in the group). Some species, like barnacles, that do produce sexually dimorphic gametes are themselves hermaphroditic, each individual producing both sperm sometimes and eggs sometimes. For a bunch of species, like bees and ants, females are diploid (developing from fertilized eggs with genes from both parents) but males are haploid (developing from unfertilized eggs only getting genes from mom). For other species, like some bugs, worms, even some mammals, females have two copies of the X chromosome while males only have 1. For most mammals, males have a Y chromosome while females don't. But how exactly does that work?

For humans, typical development of sex differentiation is triggered at around 6 weeks gestation by the transcription product of a single gene on the fetus's Y chromosome; this is why most people with a Y chromosome develop testis and produce sperm, and most people without a Y chromosome develop ovaries and produce eggs. Prior to this triggering, fetuses develop on a default 'feminine' body plan, and experiencing the trigger results in a shift to the 'masculine' body plan. But even at this most abstract definition of 'sex' (gamete morph) there are numerous exceptions to this typical pattern. Some fetuses experience the triggering of masculinization not because they have a Y chromosome but because that gene product or other chemicals that mimic it are present in the uterine environment. Some fetuses with a Y chromosome don't experience that triggering because their tissues are insensitive to the gene product their own gene produced. Some people for any of multiple reasons have a mosaic of different genetics across their cells, resulting in a mixture of effects across their body. But so far, we are just at the initial sexual differentiation in early gestation.

In typical development older fetuses, infants, children, teens, and adults produce and their tissues experience multiple waves of life stage specific hormones. Variation in the levels of these hormones, variation in the sensitivity of their tissues to those hormones, and variation in other physiological and environmental factors that strengthen or weaken the effect of these hormones all result in an incredible diversity of practically continuous variation in our bodies and behavior.

See Claire Ainsworth in Nature for an excellent summary and more detailed examples:

So, what started as a somewhat simple but abstractly binary biological concept of sex as the gamete morph that typically results from an individual's genetic and/or physical-environmental and/or social-environmental experience, ended up with bodies and behaviors that look nothing like that binary. Why should that abstract biological concept about someone's typically expected gamete morph be THE thing that anyone should use to think about their sex or that of anyone else? Aside from the relevance of biological sex to the (relative) ease of having children through your own sexual reproduction with another person, how is the morph of gamete that you or anyone else would have been expected to produce THE thing that matters in life?

Sari van Anders has done groundbreaking work on the complex psychological concept of gender/sex identity we actually have for ourselves. The finding that gave me the biggest 'Aha!' moment is that, distinct from whatever gender you may feel like, some people feel very much like one gender or the other, but many people don't or don't to the same degree. Reflecting on my own experience, I would put myself pretty low on this dimension. For example, my whole life I've had lots of experiences of being misgendered (I've probably gotten 'ma'am' on the phone more often than 'sir'). But this has never bothered me much if at all, it just doesn't really matter to me. But, that doesn't mean that other people aren't higher on this dimension and would experience these events very differently than I do! What it does mean is that I shouldn't use my own intuitions about, e.g., how hurtful it is to be misgendered, when thinking about what is a fair way to treat people or what social policy should be. But, that is exactly what we usually do, right? We use our own personal intuitions about what feels right or fair when deciding what is right or fair. The next time you hear someone invalidating anyone's experience of their own gender because of 'biological sex', I hope you will keep the practical irrelevance of this in mind. The next time someone tells you how hurtful it is when that happens to them, I hope you'll believe them.

A little history behind the Pride Month from the Library of Congress:

Lesbian, Gay, Bisexual, Transgender and Queer (LGBTQ) Pride Month is currently celebrated each year in the month of June to honor the 1969 Stonewall Uprising in Manhattan. The Stonewall Uprising was a tipping point for the Gay Liberation Movement in the United States. In the United States the last Sunday in June was initially celebrated as "Gay Pride Day," but the actual day was flexible. In major cities across the nation the "day" soon grew to encompass a month-long series of events. Today, celebrations include pride parades, picnics, parties, workshops, symposia and concerts, and LGBTQ Pride Month events attract millions of participants around the world. Memorials are held during this month for those members of the community who have been lost to hate crimes or HIV/AIDS. The purpose of the commemorative month is to recognize the impact that lesbian, gay, bisexual and transgender individuals have had on history locally, nationally, and internationally.

& Last But Not Least, Happy Pride Month!

I hope no matter how you identify, you always feel loved, supported, & appreciated.

Here's one the most beautiful voices I've ever heard that I wish was here to celebrate and see the progress we have made over the years toward equality and better understanding and supporting the LGBTQ+ community.



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