With the reveal of “grub scars” in Hiveswap Friendsim Vol 11, I wanted to get really frustrated at first, because it doesn’t make sense with a standard understanding of pupation, but instead, I’ll just accept it. However, in accepting it, I have noticed an interesting detail.
These markings are on the sides of the ribs, positioned just below the level of the pectorals, and bear the color of the troll in question’s blood. So if you wanted to keep your blood status hidden, then it’d be wise of you to keep your top covered at all times, as those markings would give you away before your blood was ever drawn.
And guess what, we’ve seen someone do this before:
The Sufferer (pants highlighted for visual clarity)
As a offspec “mutant” on Alternia, A2 Kankri Vantas would have bright red markings on his sides, signalling him as a ready victim for anyone to see. So to prevent making an instant target out of himself, the Signless (and Karkat by extension) adopted wearing chest high pants to cover up those grub scars. It’s easy to get someone to remove their shirt, but it’s a social faux pas, even on Alternia, to forcibly remove someone’s pants.
As an additional note, it’s interesting that in some of his pants (they don’t all match up from artwork to artwork, but come on, he probably has the decency to wear more than one pair of pants), he wears all gray and black, with a bit of red.
While might you think bright red would be a dead giveaway of who he is, it’s important to remember the imperial color is also bright red, and it’s socially acceptable to wear any amount of it. In fact, Redglare and Kanaya wear more red than the Signless ever did. It’s kind of a way to hide in plain sight. No sensible mutant would ever wear their color, so obviously he can’t be a mutant like they claim.
And it seems this color gambit worked so well, even Karkat followed suit:
Okay so backstory on the grub scars headcanon that was canonized, “grub scars” are vestigal markings from the troll pupation process; meaning this confirms that troll pupation is not in fact like insect pupation on earth, but more like amphibian metamorphosis with a protective shell around it, since they are likely vulnerable during this huge transition, unlike a growing tadpole.
So we know that these markings are the fleshy remnants of where those legs once were, and that the muscles that controlled their rear two sets of legs became side muscles. I have a post on what I think happens to the front two legs, but I’ll link that at the bottom.
So the markings on their sides AREN’T vestigal gills, they’re the remnants of legs from larval stage. If anything, we know that seadwellers developed gills, and we know that trolls as a whole have insectoid ancestors, so they’re not limited by having fish ancestry like mammals. If anything, it would make more sense to have the gills near their equivalent of the corotid artery, behind the jawline, where it could supply faster and larger quantities of air. Plus, if seadweller gills were on their ribs, not only would it be hard to properly get air, but they would be unable to wear shirts.
You may be thinking this is discontinuity between the forms, but there are literally no traits in common between fleshy nubs used to move around and endoskeletal jointed limbs with hands/feet at the end. There’s just no similarity, so the idea that one must become the next is just misleading. It’d be just as easy for legs to sprout out anywhere during pupation as it would for legs to develop from the legs of a troll grub.
But yeah, trolls are an alien species with distinctly insectoid and humanoid forms, with no real overlap. The idea of how the metamorphosis occurs has captivated fandom for years, and we’re finally getting some confirmed details, and frankly, I love it. If you want to read more about this topic, here’s that link I mentioned:
Cheloneuniverse 