Mystery bird: white-winged widowbird, Euplectes albonotatus

Adult male white-winged widowbird, Euplectes albonotatus (formerly; Coliuspasser albonotatus), also known as the white-shouldered or white-fronted widowbird, the cinnamon-shouldered widowbird, the long-tailed black whydah or as the white-winged whydah, photographed at Tarangire National Park, Tanzania, Africa.

Image: Dan Logen, 17 January 2010 [velociraptorize].
Nikon D300 f.8, 600 mm lens with 1.4 extender. f/8, 1/640 sec ISO 500

Question: If I told you this African mystery bird species is sexually dimorphic, what am I talking about and what does this mean for this species' natural history?

Response: This is an adult male white-winged widowbird, Euplectes albonotatus, in breeding plumage. This species is sexually dimorphic, where there are marked differences in colour and form between adult males and females. Not only does this species show strong differences in colouration (known as sexual dichromatism), but the males also have large, showy tail feathers that they use in courtship displays. Female widowbirds choose their mates on the basis of their plumage, favoring more colourful males with long tails. One could almost say that males of this species are true ladies' men; owing their appearance to female choice and solely for the purpose of attracting females.

Whenever there is a strong difference in form and colour between males and females of a species this implies that females are selecting to mate with males that have exaggerated characters. Typically, in such systems, males are not monogamous and do not provide any parental care. Instead, males hold territories and court females and try to mate with as many of them as they can.

You are invited to review all of the daily mystery birds by going to their dedicated graphic index page.

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