10. African Goshawk This bird illustrates one difficulty in identifying birds. Books, generally, give you a nice picture, and that’s how you expect it to look. But the immature African Goshawk, for example, has a dark eye and dark spots on its breast arranged in longitudinal rows from chin to tail, while the adult has a yellow eye-ring and narrow dark lines across its breast, this time horizontally. And what’s more, there is a dark ‘morph’ of this bird which is just like the picture in size and shape but is entirely black (except for the yellow eyes). Morphism occurs in a number of birds. It is not, as you might think, a kind of reversed ‘albinism’, which is a genetically caused lack of any pigment and which does occur in birds as in other animals. Dark morphism, or ‘melanism’ to give it its proper name, is caused by an excess of the pigment, melanin, which causes the feathers to have a dark or even black colour. You notice that most birds’ wings have large dark or black feathers along the back edge of the wing; this is because melanin also makes the feathers stronger under strain in flight. Birds of AFRICAMA House 24 Birds of AFRICAMA House 25