Cyanomitra olivacea
C. olivacea, Olive Sunbird, populations show marked phenotypic differentiation across the forest–savanna ecotone. In addition, C. olivacea shows differences in blood parasite prevalence along the forest–ecotone gradient, suggesting the possibility of divergent selection in response to disease. These findings add to the growing evidence suggesting that the forest– ecotone boundary in sub-Saharan Africa is an important driver of population divergence.