The players will be able to correctly classify contemporary and extinct chordates according to physical characteristics. Players try to create the classification hierarchy. Players must correctly identify which Genus belongs to which Order, and which Orders belong to which Class. This can be done from memory, or by reading the Genus characteristics on the cards and matching with them with correct Order characteristics. As players obtain cards they will be able to place them in the play area if a higher card has already been placed in the play area. (for example a Genus card can only be placed in the play area if and only if it's Order card is available.) The game is won when a complete hierarchy is built. Components: 126 cards - 21 Order cards - 35 Class cards - 70 Genus cards