48. White-bellied Tit Though the White-bellied Tit is quite common in Kenya and Tanzania, it’s not widespread elsewhere in Africa, with some populations in Cameroun. A very black and white bird, for both sexes. Why are some birds brightly coloured and others dull? Patterned browns and buffs are obviously good camouflage in many African contexts, especially for birds incubating eggs and feeding chicks, often but not always females; but also for those whose hunting techniques require stealth, like many of the owls, for instance. Some birds, like the snowy owl and the ptarmigan change into snow-coloured plumage when winter comes. Perhaps contrasting black and white has a camouflaging effect in shady conditions, breaking up the silhouette so that the bird is less easily noticed. Bright-coloured birds must be the result of some kind of evolutionary calculation: the advantages of bright colours – for breeding or for species recognition – presumably outweigh the disadvantages of the greater visibility in the eyes of their predators. The way those balance out will vary widely in different circumstances, so the calculations cannot be simple. But what is sure is that all those who miscalculated have either already gone extinct or presently on the way out. Birds of AFRICAMA House 101