What good are feeemoids anyways?

How would we determine the ideal sex ratio in a world where males make eggs

Last week I got to see scientist Katsuhiko Hayashi, professor at Osaka University, present on how he and his team had created healthy mice pups from the DNA of two male mice. Incredible. But don’t get too excited, this isn’t about to hit the market anytime soon - Katsuhiko expects it will take at least 5-10 years to reproduce and test this technology on humans, so you’ll have to wait on the biologically pure gaybies. Still, it’s a pretty cool proof of concept. 

Image generated with Chat-GPT 4. Prompt “draw two male mice with pride shirts on who are holding hands while smiling at their mouse babies”

Hayashi is a leading researcher in the field of in vitro gametogenesis (IVG) which involves the creation of gametes outside of the body from any cell. Starting with mouse skin cells he genetically modified them to create induced pluripotent stem cells (iPS cells). He was then able to differentiate these iPS cells into gametic cells which he matured into functional gametes outside of the body. But stem cells still have sex - iPS cells created from a female mouse will have XX chromosomes while those created from a male mouse will generally have XY. So the gametes generated from a female cell will be eggs while those from a male cell will be sperm. Getting male cells to create eggs involves additional steps. 

According to this article in Nature, during the process of creating iPS cells about 3% lose their Y chromosome. 

The team then isolated these Y-less cells and treated them with a chemical that causes errors during cell division. Some of those errors resulted in cells with a duplicated X chromosome, effectively making them female cells. The team then took these through the complex and laborious process required to make an egg.

Based on this description, and my very shallow understanding of the process, this seems to imply that getting sperm cells from a female wouldn’t be possible with this technology since female cells have no Y chromosome. And I’ll also note that while they did get live pups by transferring these fertilized embryos, the Nature article says that “Only 7 live pups resulted from 630 embryo transfers.” Not a great hit rate.

Still, it seems plausible that this technology will be able to create functional human gametes from any cell within a few decades. And as someone interested in fertility decline and reproductive technology I find this exciting. It could allow women to produce healthy eggs at any age thereby extending their fertility window, almost without limit. And if women’s fertility extension is paired with life and/or health span extension this could allow for later family formation without the corresponding limits on family size or parenting ability.

That’s cool. But learning about this technology caused me to meditate on more bizarre sci-fi futures. Let’s imagine a world where this technology is easy to use and accessible to all humans. Let’s also assume that we’ve perfected artificial womb technology and that almost everyone uses it. Maybe there are some trad heteros who continue to insist on giving birth the old fashioned way, but the rest of us simply laugh at god as the sweet fruit of the tree of knowledge allows us to evade our punishment for its consumption. 

Image generated with Chat GPT-4. Prompt “draw adam and eve eating from the tree of knowledge with juice dripping down their faces while laughing at god in the sky as their baby grows in an artificial womb nearby”

What percentage of men and women would we want in this imagined future? Assuming most people are still heterosexual, we’d probably stick with something close to 50-50. But maybe we’d instead modify all our genes to create a world brimming with gay men! After all, according to Ginevra Davis “A mind in a female body is a mind shrunken, tweaked.” If her description of the difficulties of femaleness is accurate, a life apparently spent managing never ending and poorly understood pain, who would choose such a fate for their baby? 

To be clear I did not find Ginevra’s piece at all representative of my experience as a female. Females surely have differential ailments relative to males, and many of these are in some way related to our capacity to bear children, but outside of pregnancy (which as far as I can tell Ginevra has also not experienced) they are typically pretty manageable! Her piece also failed to mention that men die 6 years younger than women on average which seems like a pretty significant downside to being “a mind in a male body”. 

While getting your period each month can range from a minor inconvenience to something that is truly distressing and painful, the male experience of puberty also sounds pretty intense! As a female I didn’t spend years unable to think of much other than sex and how I could find a woman to have it with me, I didn’t deal with unwanted boners in awkward situations, I didn’t worry about whether I’d be able to “perform” sexually and I wasn’t flooded with hormones that made it more difficult for me to control my aggressive impulses. Menopause sounds like a bitch, and I hope we have better ways to manage it by the time I get there, but I’d still take the trade for an extra 6 years of life. 

Males are obviously physically stronger and faster than females, but I’d bet that in this future tech enabled world these attributes wouldn’t be all that valuable. And with no burden of pregnancy for women it could be tough to make the case that it’s better for a given individual to be one sex rather than the other. But what about the perspective of society as a whole? If males tend to have higher variability (in personality traits, intelligence, aggression etc.) it might seem preferable to have mostly males, since there’s a higher chance that any given male will be a genius that moves society forward. But the flipside, of course, is that there’s also a higher chance that he’ll be some kind of violent criminal! Perhaps we ought to stick with 50-50 after all?