Shell Shocked! I was out shell collecting when—surprise!—a tiny hermit crab popped out of a shell I had just picked up. These little crustaceans don’t grow their own shells—they rely on empty ones left behind by sea snails. But here’s the wild part: if they can’t find a proper shell, they’ll use whatever fits… even plastic like bottle caps. Pollution has made it harder for hermit crabs to find good homes, which is why you’ll sometimes see them squeezing into anything they can, from broken shells