/jp/ - Otaku Culture

>>7176634
Those are probably urticating hairs, found in tarantulas and caterpillars (millipedes, caddisflies and beetles can also have them, albeit rarely.) The former usually kick them towards potential threats, though skeleton tarantulas have urticating hairs on the pedipalps and launch them by brushing their chelicerae against the palps instead (fortunately those hairs are present only on a specific area, otherwise mating would be quite painful for them - spider mating involves the male inserting the tips of his palps into the female.) The resulting mist of tiny barbs effectively wards off many would-be predators (and unwitting humans) as the hairs hurt quite a bit - especially when embedded in eyes or the nose. They act both by mechanical irritation and triggering immune system reactions, their severity depends on the species and the type of hair kicked and the location affected, itching powder most likely uses the milder variants (as the more potent ones result in very painful rashes). At any rate, Yamame is not a tarantula, so perhaps it's safe to assume her hairs wouldn't irritate the skin.

>>7176678
Thank you, this is a great read. And speaking of being covered in eyes, it seems echinoderms managed to pull it off quite literally - sea urchins have photoreceptors over their entire bodies and the boundaries of their "eyes" are defined only by their spines, which block light coming from other directions (which also means the more dense a sea urchin's spines are, the better it can see.) The brittle star Ophiocoma wendtii likewise has calcite lenses lining its body, focusing light onto the photosensitive nerves below. Like Argus Panoptes they are entirely covered in eyes, and the whole organism acts as one big compound eye.