Intra-species recognition
Intra-species recognition is the recognition by a member of a species of a conspecific (another member of the same species). In many species, such recognition is necessary for procreation.
Different species may employ different methods, but all of them are based on one or more senses (after all, this is how the organism gathers information about the environment). The recognition may happen by chemical signature (smell), by having a distinctive shape or color (sight), by emitting certain sounds (hearing), or even by behaviour patterns. Often a combination of these is used.