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Résumé :
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A molecular phylogeny is not yet available for the widespread, medium-sized and ecologically uniform African Goshawk complex, which shows important geographical variation size and colour. Based on plumage characteristics and habitat preferences, I recognise two paraspecies: a rather cryptically plumaged woodland group (tachiro); and a colourful equatorial forest taxon (toussenelii). The rather colourful form on the Ethiopian highlands is isolated and could be considered as a third paraspecies. However, the form on Pemba island, obviously derived from nearby woodland parental stock (tachiro s.l.), also has the forest characteristics of small size, colourful female and poor sexual plumage dimorphism. This demonstrates the phenotypic plasticity within the complex. Morphology is related to habitat, which includes a different balance of social characteristics and it is also seemingly related to the presence of congeneric species. I suggest that male selection for a quality partner provoked the colourful females in forest and the heavy females in woodland. A postjuvenile 'junior adult' male plumage, which resembles the adult female in colour, is present in the East African woodland form and could help these birds to survive near adult-plumaged territory holders. A peculiar juvenile, which may either be a mimic of the Black Goshawk or a character displacement of the Chestnut-flanked Sparrowhawk, occurs in the Lower Guinean forms.
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