I am SO into the science behind kink, particularly snz kink, and those theories were fascinating!!! I truthfully think it has someone else to do with besides simply environment tho bc so many snz fuckers show interest in illness media far before they would be exposed to a larger environment or form any sort of non familal relationships !! The idea of opposing immune systems seems v intriguing tho!!
Yeah, I absolutely agree that this kink is more than just environmental factors. Not too long ago I made a post about how interesting it is that there are so many autistic snzfuckers out there (myself included), and, more broadly, how a disproportionate number of snzfuckers have some kind of auditory processing abnormalities. (I think I forgot to get that post reblogged to this new blog. I’ll fix that in a second.) As far as I’m aware, neuroatypicallities like those are largely genetic.
I can’t claim to have ever studied kink science (which is a goddamn shame, given how many evolution and animal behavior courses I’ve been through), but this all makes me think that there isn’t a single specific snz kink gene. There are probably several genetically coded factors that make it likely for the kink to develop early on.
And if that’s the case, you’re right and we’d rule out hypothesis 1 because it assumes that the same genetics underpin all kinks.
So if we assume that the genetic factors contributing to having a snz kink are unique-ish, it comes down to two possibilities. Either the kink is beneficial for survival and reproduction, or the kink is neutral/slightly negative, but there’s not enough selection pressure to remove it from the gene pool.
The kink being just kinda neutral/not detrimental strikes me as the most likely situation. Evolution is such a chaotic mess of a process, and most mutations are, in fact, neutral or deleterious. There’s also the complication of the genes that underpin the snz kink also being linked to other traits, and selection will act on those traits as well.
But I do have yet another fun explanation for why having a snz kink may be evolutionarily beneficial. So with non-dangerous illnesses (like the common cold), the vast, vast majority of symptoms and just feeling shitty are not due to the virus. They’re due to your immune system’s response. Snotty? Your body’s making mucus to flush out the virus. Sore throat? Your throat’s inflamed, which is something your body does to get white blood cells to the site of infection faster. Exhausted? All your body’s energy is focused on this immune response right now, you don’t have energy to spare.
And here’s the thing. People with stronger immune systems, ones that would adequately protect them from from illnesses that are actually dangerous, also tend to be the same people who are more symptomatic from regular colds.
This is a long winded way of saying that maybe the kink is The Pinnacle of Human Evolution (lmao imagine) because it encourages us to go for partners who definitely have, uh, more reactive immune systems, which happen to also be the people who are least likely to die of plague or something.