Many birds are sized up by prospective mates solely by certain visual
clues. There are scientists who believe that female birds can deduce
such things as the fitness of a male, his ability to parent, and
the quality of a nesting site by either examining him or his territory.
As a result, evolution has produced some pretty interesting adaptations
to help males attract females, the first and most obvious of which
is colorful plumage.
Birds have fantastic eyesight with a keen ability to discern colors.
Their means of finding a mate is therefore, mainly visual. The majority
of male birds develop specially colored plumage, called breeding
plumage, in the spring. The Robin and his red breast are a familiar
example that springs to mind. Similarly, the male flamingo will
turn bright pink, and the male cardinal, a deeper red. Some birds
develop more elaborate plumage than a simple color change, but it
is not as common because it interferes with the bird’s ability
to hide from predators. An example of this is the Peacock, a familiar
example of a bird with elaborate plumage, uses his "tail of
eyes" in a grand display to attract females.
Whether brightly colored or not, many birds put on shows called
"displays" for females to try and get their attention.
The majority of birds have quite simple displays such as raising
the beak upwards or the flapping of wings. There are, however, other
birds that have evolved elaborate displays when competition for
females is great.