Animal behavior can be inherited through genes, or it can be learned through interactions with the environment. Behavior that is influenced by genes is molded by natural selection and other evolutionary forces. As a result, most genetically based behaviors should increase the fitness, or reproductive success, of the individual. Pheromones, that are chemicals used for communication, mimicry, which is an example of coevolution, or the evolution of one species in response to new adaptations that appear in another species, and instinct behavior, which is a behavior that is inherited through genes, may be described and their selective advantages may be discussed.
Chemicals used for communication are called pheromones. Chemicals that cause immediate ad specific behavioral changes are releaser pheromones. For example, many male mammals spray urine throughout their territories, especially along their borders as a releaser pheromone, to warn other animals of the same species to keep out. Chemicals that cause physiological changes are called prime pheromones.
For example, queen bees, queen termites, and queen ants secrete primer pheromones that are eaten by workers. The pheromone prevents development of reproductive ability. In the case of pheromones, selective advantage is demonstrated in courtship behaviors. For example, reproductively receptive female silkworm moths attract male silkworm moths by emitting releaser pheromones into the air from several kilometers away. Pheromones then trigger courtship behaviors when the moths come together.
Mimicry occurs when two or more species resemble one another in appearance. There are two kinds of mimicry, Batesian and Mullerian mimicry. Batesian mimicry occurs when an animal without any special defense mechanism mimics the coloration of an animal that does possess a defense. For example, some defenseless flies have yellow and black markings but are avoided by predators because they resemble the warning coloration of bees. Mullerian mimicry occurs when several animals, all...