Transmission of information from one animal to another by means of sound, visible sign or behaviour, taste or odour, electrical impulse, touch, or a combination of these. Most animal communication uses sound (e.g., birds calling, crickets chirping). Visual communication usually indicates an animal's identity (species, sex, age, etc.) or other information through specific characteristics (e.g., horns, patches of colour) or behaviour (e.g., the bee's "dance" describing a source of food). Chemical communication involves pheromones (chemical signals) produced by the animal's endocrine system. Eels and some other fishes use electrical impulses to communicate