The African rift lakes form
Deep basins along the rift fill with water and become engines of evolutionary novelty.
- When
- —
- Duration
- 6.7 million years
- Known to
- ± 2 million years
- Era
- Miocene, Cenozoic
As the East African Rift deepens, its basins fill to form Tanganyika, Malawi and their neighbours — lakes so deep and long-lived that they function as independent evolutionary theatres. Tanganyika alone holds around 250 endemic cichlid species descended from a handful of founders, and the rift lakes collectively contain more freshwater fish species than any comparable area on Earth. Their sediments also archive East African climate in fine detail, which is how the environmental backdrop to hominin evolution is reconstructed.