News release

From: Springer Nature

Moroccan hominin fossils shed light on the emergence of modern humans (N&V) *IMAGES*

Hominin fossils discovered in Casablanca, Morocco, which have been dated to about 773,000 years ago, may be close ancestors of modern humans. These remains show a mix of old and modern features, potentially placing them near the point where African and Eurasian human lineages began to diverge. The findings, published in Nature, provide insights into African populations before the earliest known Homo sapiens and provide evidence for an African origin of our species.

The last common ancestor of modern humans, Neanderthals and Denisovans, are thought to have lived around 765–550 thousand years ago. However, there have been debates about where these ancestors first appeared. Previous discoveries, such as Homo antecessor in Spain, suggested possible ancestral links in Europe, but well-dated African fossils of similar ages have been rare, leaving a gap in the African record.

Jean-Jacques Hublin and colleagues analysed fossils unearthed from a cave called “Grotte à Hominidés” at Thomas Quarry I in Morocco, including two partial mandibles, numerous teeth and vertebrae. Analysis of the surrounding sediments shows that the fossils are from a time close to a major shift in the Earth’s magnetic field, about 773,000 years ago, giving them a similar age to H. antecessor. However, the new fossils are morphologically different from H. antecessor, suggesting that regional differentiation between Europe and North Africa was already present by the late Early Pleistocene (around 1.8 million to 780,000 years ago). The Moroccan fossils combine ancient features seen in species such as Homo erectus with more modern traits found in H. sapiens and Neanderthals. For example, their molar size patterns resemble those of early H. sapiens and Neanderthals, whereas their mandible shape is closer to those of Homo erectus and other African archaic humans.

The Moroccan fossils may not be the last common ancestors to modern humans, Neanderthals and Denisovans, but may be close ancestors, the authors note. The findings support an African rather than Eurasian ancestry for H. sapiens, the authors conclude.