ik this isn't your specialty, but can you talk about heteropaternal superfecundation? Its when twins have two separate biological fathers, bio is my niche !!
Heteropaternal superfecundation.
Two eggs, same ovulation cycle, fertilized by sperm from different males.
Fraternal twins, distinct biological fathers, requires hyperovulation and two fertilization events within the same fertile window.
Documented in assisted reproduction cases, and not as rare as people assume.
The phenomenon is more common in species that naturally produce large litters, which is part of why it took so long to document reliably in humans.
Genetically, the twins share roughly 25% of their DNA rather than the usual 50% for fraternal twins, since they have different paternal contributions.
From a forensic genetics standpoint, it's caused significant complications in paternity cases historically, which is its own rabbit hole entirely.
There's also superfetation, which is the even rarer occurrence of a second pregnancy developing while one is already in progress.
Different mechanism, equally chaotic reproductive biology.
Anyways, I was going to leave it there but some people in this fandom (my mod included) have apparently decided this is the mechanism by which Xeno and Stanley are reproducing, and I have been made aware of this against my will.
I'm a scientist. I'm not touching that.
Scientifically or otherwise.
Good question though, and great niche!
// Or maybe they'll adopt Gen and Senku tbh.
Also, I'm so, so sorry for the late reply on this ask! I didn't realize it was still sitting in my drafts. 😭
That's entirely my bad. To make up for it, if you ever send another ask, just let me know it's you, and I'll answer it first over anyone else's. I hope that doesn't get abused by other people sending in anonymous asks, but I'll have faith in this community.