Is Bioko Island on 'The Wrong Side of Africa'?

Allan Krill

It depends if you are interested in where apes and humans could easily survive, or where bones and fossils could easily survive.

All African apes live in the green rainforest areas. Billions of mammals have lived or evolved in those rainforest areas, but not a single ape or mammal fossil has ever been found there. Bones decay quickly in those areas, so they do not become fossils.

If your career is to find and publish fossils, you can ignore the green areas. But if you want to understand apes and humans and their evolution, I think you should focus on the genetics (not the fossils) of apes and humans. 

(Bioko is an exotic volcanic island in the green rainforest area.)

Maps from Jonathan Kingdon (2013): Mammals of Africa, Bloomsbury Publ., 3763 p.