Sometimes when a new shell turns up, hermit crabs will form a line, biggest to smallest, to see which animal fits the new shell. The next smallest will take that crab’s hand-me-down home, and so on.

When Tim Jerman was a child, he couldn’t decide whether to become a marine biologist or an artist. So he became an artist who created intricate glass sculptures of aquatic life. For “ Hermit Crab ” ...