Paleontologists have discovered protein sequences within dense enamel tissues of ancient rhinocerotid and proboscidean fossils collected at sites of Buluk and Loperot in the Turkana Basin, Kenya. The Turkana Basin within the East African Rift System preserves fossil assemblages that date back more than 66 million years; Green et al. collected powdered samples for paleoproteomic analysis from the dense interiors of enamel from large herbivores...