Turns out it wasn't the doing of aliens who'd overshot a Nebraska cornfield or out-of-work art students with scuba gear. No, it was a masterwork by an amorous and talented male Takifugu rubripes, the poisonous pufferfish eaten by only the bravest sushi connoisseurs.
Yoji found a series of small male fish working tirelessly, day in and night out, to craft these mate-attracting marvels using a single fin.
Confocal image of a squid embryo. All nuclei are stained with DAPI (blue). Phalloidin staining reveals neural structures (red), while cilia on the surface of the embryo are highlighted by acetylated tubulin staining (green).