Scientists have discovered ancient human remains that could represent a crucial link in our evolutionary history.

Fossils, including bones and teeth, dating back 773,000 years, were unearthed in a Moroccan cave, displaying a mosaic of modern and primitive features. 

The face was relatively flat and gracile, resembling later Homo sapiens, while other cranial features, such as the brow ridge, brain size, and overall skull shape, remained archaic, more similar to earlier Homo species.

Because the specimens showed mixed traits, the team suggested it was a 'missing link' of African and Eurasian lineages that lived on both sides of the Mediterranean.

The discovery also upends the traditional view that Homo sapiens first arose in Africa and later replaced other hominin species during migration. 

It supports the idea that early human populations left Africa well before fully modern traits had evolved, spreading across Asia and Europe and gradually diverging into distinct groups over time. 

Together, these characteristics place the Moroccan fossils at a critical point in human evolution, near the divergence between African and Eurasian lineages, and offer new evidence for how early humans developed the facial and dental features that would later appear in Homo sapiens and Neanderthals. 

The find reshapes our understanding of the timeline and geography of human evolution, showing that modern traits emerged gradually in multiple populations across Africa long before fully modern humans appeared. 

Researchers said the fossils, lower jawbones of two adults and a toddler, as well as teeth, a thigh bone and some vertebrae, were unearthed in a cave called Grotte a Hominides at a site in the city of Casablanca. 

The cave appeared to have been a den for predators, with the thigh bone bearing bite marks suggesting the person may have been hunted or scavenged by a hyena. 

Paleoanthropologist Jean-Jacques Hublin, lead author of the study, said: 'I would be cautious about labeling them as 'the last common ancestor,' but they are plausibly close to the populations from which later African - Homo sapiens - and Eurasian - Neanderthal and Denisovan - lineages ultimately emerged.'

'The fossils show a mosaic of primitive and derived traits, consistent with evolutionary differentiation already underway during this period, while reinforcing a deep African ancestry for the Homo sapiens lineage,' Hublin added.

The oldest-known fossils of Homo sapiens, dating to about 315,000 years ago, were also found in Morocco, at an archaeological site called Jebel Irhoud.

Knowing the age of the Grotte a Hominides fossils, based on the magnetic signature of cave sediments surrounding the fossils, helped the researchers assess how this population fit into the human family tree.

Genetic studies suggest that the last common ancestor of modern humans, Neanderthals, and Denisovans lived roughly 765,000 to 550,000 years ago. But where these ancestors lived and what they looked like is still uncertain. 

Now, the new fossils, found at Thomas Quarry I (ThI-GH), shed new light on this story. 

While similar in age to Homo antecessor, these fossils are morphologically distinct, showing a mix of primitive traits and features seen in later Homo sapiens and Eurasian archaic humans. 

Homo antecessor is an extinct species of early human that lived roughly 1.2 million to 770,000 years ago, primarily known from fossils found at Atapuerca, Spain. 

One jaw found in the cave was nearly complete and shows a long, low, and narrow shape with a slightly sloping front, similar to Homo erectus, but with teeth and internal features that resemble both Homo sapiens and Neanderthals. 

The front teeth of the jaw were heavily worn or broken, but their roots are mostly preserved. 

The right canine was slender and small, similar to modern humans and much smaller than in other early and Middle Pleistocene hominins like Neanderthals. 

Some incisors also fell within the size range of early and recent Homo sapiens, though their roots are longer, closer to Neanderthals, but smaller than Homo erectus. 

Homo erectus was a long-lived species of archaic human that lived from nearly two million years ago until at least 140,000 years ago, being the first hominin to migrate out of Africa into Asia and Europe

The molars on the jaw had a mix of traits: they resembled North African Middle Pleistocene teeth and shared some features with H. antecessor from Spain, but they also retained archaic characteristics seen in African H. erectus. 

The other jaw appears more robust and shares traits with European Middle Pleistocene hominins and Neanderthals, while retaining some modern internal characteristics. 

Unlike some European specimens, the specimen's teeth were more widely spaced and lacked shovel-shaped incisors. 

The teeth showed a mix of primitive and advanced features, including a molar size pattern more typical of Homo antecessor, Neanderthals and modern humans. 

Beneath the jaw, researchers found eight vertebrae likely belonging to the same small-bodied adult. 

The fossils were buried by fine sediments over time, and the cave entrance was sealed by a dune, enabling exceptional preservation of the remains. 

Hundreds of stone artifacts and thousands of animal bones were discovered in the cave.

The Grotte a Hominides human fossils are roughly the same age as fossils from a site called Gran Dolina near Atapuerca in Spain that represent an archaic human species called Homo antecessor. In fact, these fossils share some traits.

'The similarities between Gran Dolina and Grotte a Hominides are intriguing and may reflect intermittent connections across the Strait of Gibraltar, a hypothesis that deserves further investigation,' Hublin said.

Hominins from this period possessed body proportions similar to those of modern humans but with smaller brains.