Breeding is a natural part of the animal kingdom. Animals need to seek out a mate, with males and females often covering long distances in search of the right mating signal.
Across the animal kingdom, species have developed myriad ways to advertise for a mate. Males possess territory to attract their mates and females have devised ways to announce their presence to the searching male.
When together, animals have further problems to solve particularly when it comes to language. Males need to switch from a language of aggression to one that will encourage a female to stay with them. Oddly, the languages of threat and courtship are remarkably similar. On top of this, there are other more characteristic signals involved in courtship, such as indicating suitable nesting sites, or feeding the mate.
Every species of animal has developed its own special system. These distinctive messages act like passwords, preventing animals of different species trying to breed with one another. It is this language of courtship that has given rise to some of the most beautiful and extraordinary sights and sounds in all of nature.