Shifting Landscapes, Shifting Lineages: What a Half-Century of Fossils from the Omo–Turkana Basin Is Telling Us Now

A Basin That Resists Simplification

Spend long enough studying human origins and the Omo–Turkana Basin begins to feel almost mythic. This vast sweep of East African sediment, stretching from southern Ethiopia to northern Kenya, has long been treated as paleoanthropology’s equivalent of an archive: dusty, sprawling, occasionally confounding, but indispensable all the same.

Since the late 1960s, thousands of researchers, field assistants, and local fossil hunters have walked its eroding badlands. They collected bones that would anchor debates about bipedalism, chewing biomechanics, and the dawn of Homo. The result is an assemblage that now makes up roughly one third of Africa’s known hominin fossil record from the past seven million years.

Map of the Omo-Turkana Basin showing the labeled geographical parts color coded for the western (orange), northern (green), and eastern (blue) areas (modified from Feibel, 2011). Credit: Journal of Human Evolution (2025). DOI: 10.1016/j.jhevol.2025.103731

Yet until recently, much of that information lived in separate pockets of literature, often shaped by the goals or traditions of specific field projects. François Marchal and colleagues have now folded 117 publications into the most comprehensive catalog of the basin’s fossil hominins to date, spanning 1,231 specimens representing an estimated 658 individuals.

Their new synthesis¹ does what earlier inventories could not: treat the basin as a single, coherent entity. And once the pieces are layered together, a very different picture begins to emerge.

“The basin behaves less like a uniform archive and more like a set of neighboring landscapes that each choose their own chapters of the story to preserve,” says Dr. Leila N’Dour, a paleoanthropologist at the University of Dakar.