Furthermore, male and female plumage is indistinguishable in ultraviolet and visible light.
There are two theories regarding to the evolution of male ornamental plumage, i.e. the train.
This species is 22-24 cm long and shows geographically variable male plumage amongst its six subspecies.
There are significant racial variations in the male plumage (see Taxonomy).
Some abnormal females may later in their lifetime get some male plumage.
I noticed that his crew-cut had recently been trimmed; was even the Hawaii shirt serving the function of male plumage?
The yellow shoulders persist in all male plumages, whether breeding or non-breeding.
The male plumage is a striking combination of black and bright blue.
The three groups have differing male plumages, distinctive calls, and are allopatric; further study is needed.
Tropical African forms have less grey in the male plumage.