The infamous tongue-eating louse is one of nearly 400 species belonging to a family of fish parasites. Some latch onto their host’s head, others suck blood from fish gills, and others still burrow into fish flesh. But the Cymothoa exigua goes specifically for fish tongues. How do these parasites do it, and why? Niko Zlotnik explores the strategies tongue biters use to find a fish to call home. Lesson by Niko Zlotnik, directed by Flaka Kokolli, Flammorum Animation Studio.