A clade is a complete branch of the evolutionary family tree. In these games, the major clades are mammals, arthropods (“bugs”), and sauropsids (reptiles and birds together). Each major clades includes three smaller clades, such as “bats” or “turtles.” Each smaller clade is linked to one of three environments: water, land, or air. The cards show which sorts of animals are more closely related to each other and which less closely. Cards are laid out on the table twelve at a time, and players compete to find a “triple,” which is three cards that go together in a pattern. Each player also has a personal card that only they can use. Bonus cards add an exciting element of chance. The player who spots the most triples is the winner.