Fossil teeth dating back to the Middle Pleistocene roughly 450,000 years ago could help to piece together the timeline of ancient humans in Eurasia.
Researchers have discovered two sets of teeth now thought to be among the oldest human remains found on the Italian Peninsula.
The remains from the sites of Fontana Fanuccio and Visogliano in Italy suggest Neanderthal dental features had already evolved by the Early-Middle Pleistocene, supporting theories that the Neanderthal lineage diverged from our own early on.
The ancient teeth discovered in Italy add new clues to the complex path of human evolution hundreds of thousands of years ago.
They are among very few fossil human remains in Europe from the Middle Pleistocene.
In the new study published to the journal Plos One, researchers examined teeth found in Fontana Fanuccio about 31 miles (50 km) southeast of Rome, and Visogliano, located 11 miles (18 km) northwest of Trieste.
Micro-CT scans and morphological analyses of the Pleistocene teeth revealed distinct Neanderthal-like features compared to other human species.
The teeth from both sites were found to share similarities with Neanderthals, with marked differences from those of modern humans.
As experts have long debated the identities and relationships of ancient humans in Eurasia during the Middle Pleistocene, the discovery could help to put some arguments to rest.
‘The remains from Fontana Ranuccio and Visogliano represent among the oldest human fossil remains testifying to a peopling phase of the Italian Peninsula,’ said Clément Zanolli of the Université Toulouse III.
‘Our analyses of the tooth internal structural organization reveal a Neanderthal-like signature, also resembling the condition shown by the contemporary assemblage from Atapuerca Sima de los Huesos, indicating that an overall Neandertal morphological dental template was preconfigured I Wester Europe at least 430 to 450 ka ago.’
According to the researchers, the teeth also show significant differences to other teeth from this time period found in Eurasia.
This suggests the region was once home to several lineages of human species, hinting at the complexity of human evolution in the Middle Pleistocene.
‘Results revealed more complex population interactions through time and space than previously established,’ the researchers explain in the paper.
‘In particular, nuclear genomic data indicate closer relationships between the SH hominins and European Neanderthals than with the Siberian Denisovans.’
According to the researchers, the ‘genetic and morphological evidence now suggest an early divergence between Neanderthals and modern humans, likely around the Early Middle Pleistocene transition.’