An antelope found in sub-Saharan Africa, belonging to one of three genera and 22 species, ranging in weight from 3 kg (blue duiker, Philantomba monticola) to 70 kg (yellow-backed duiker, Cephalopus silvicultor). They inhabit rainforest, except for the grey common duiker (Sylvicapra grimmia), which lives on the savannah grasslands.