Nature has a beautiful way of displaying civilization in its creatures.

Hermit crabs rely on shells to protect themselves from predators and the elements.

These crabs use the scavenged shells of other animals as their homes. As the crabs grow, they periodically need to move to bigger shells. When a new shell appears on the beach, the cramped crabs will form a orderly queue based on size. Some scientists call this a “vacancy chain”. They change shells in sequence, with each crab moving into the next biggest shell as the previous occupant leaves.