Why does more of Africa lie north of the Equator than south of it?

The Equator bisects the African continent almost equally, placing much of its landmass within the tropical region. However, the continent is not perfectly symmetrical across the Equator.1

The reason more of Africa lies north of the Equator than south of it is due to the significant east-west bulge formed by western Africa in the northern portion of the continent. In contrast, the continent narrows considerably as it extends southward.21