Sexual Dimorphism
Male and female birds show very strong sexual dimorphism. Males are much larger; they have large red fleshy wattles and comb on the head and long, bright gold and bronze feathers forming a "shawl" or "cape" over the back of the bird from the neck to the lower back. The tail is composed of long, arching feathers that initially look black but shimmer with blue, purple and green in good light. The female's plumage is typical of this family of birds in being cryptic and having evolved for camouflage as she alone looks after the eggs and chicks. She also has no fleshy wattles or comb on the head.
During their mating season, the male birds announce their presence with the well known "cock-a-doodle-doo" call or crowing. This serves both to attract potential mates and to make other male birds in the area aware of the risk of fighting a breeding competitor. A spur on the lower leg just behind and above the foot serves in such fighting. Their call structure is complex and they have distinctive alarm calls for aerial and ground predators to which others react appropriately.
Read more about this topic: Red Junglefowl