Geological evidence and geodynamic modelling suggest that the Nile river system has been largely stable since its origins ~30 Ma. The Nile could have provided a long-term migration route for vertebrates including hominins between Eastern and Northern Africa. However, other geological data contradict such an old stabilisation of the course of the Nile. Fieldwork along the middle stretches of the Atbara River, the last tributary to the Nile before it crosses the Sahara, provides evidence...