The upper part of this soft-bodied animal forms keratinized skin much like a fingernail to repel attacks from spearworms. Larger animals simply turn them over or swallow them whole. Though not a true shell, the tough skin of the back does offer some protection.
Hello, my name is Dan. I am an author, artist, explorer, and contemplator of subjects large and small. I like bacon. I like pizza. I like bacon pizza. I enjoy long walks on the beach, but prefer the mountains. I am a huge fan of Jesus. When I grow up, I want to be just like him and create my own universes.