An ant skull here. A fly’s wing there. These piles of insect parts aren’t a sloppy spider’s leftovers: They’re the gruesome shell of the bone collector caterpillar! This rare carnivorous species lives in Hawaii. It shares a habitat with cobweb spiders, gobbling up whatever uneaten insect parts the spider leaves behind. The caterpillar weaves a case around itself to hide from predators. Then it decorates the case with the “bones” of its buggy buffets! This disgusting disguise lets the caterpillar wander through webs without becoming the spider’s next meal. “When the spider runs out, it tastes its own dirty laundry [covering the caterpillar’s case],” says Dan Rubinoff of the University of Hawaii, who co-discovered the species. “So it’s like, ‘This isn’t food!’ And leaves the caterpillar alone.”