Fossilized teeth discovered in Italy have provided significant insights into the evolutionary history of early humans, shedding light on the complex and intricate nature of human development during the Middle Pleistocene. The discovery, published in PLOS ONE on October 3, 2018, by Clément Zanolli from the Université Toulouse III Paul Sabatier in France and his team, reveals that Neanderthal dental features had evolved by approximately 450,000 years ago. This discovery adds to the growing body of evidence suggesting a more nuanced and complex period of human evolution during this time.
The teeth in question were found at two significant archaeological sites in Italy: Fontana Fanuccio, located about 50 kilometers southeast of Rome, and Visogliano, situated roughly 18 kilometers northwest of Trieste. These sites are home to some of the oldest human remains found on the Italian Peninsula, with the teeth dating back to around 450,000 years ago. At this time, the Middle Pleistocene was a period of significant evolutionary development and diversification for early humans, making any fossil discovery from this period immensely valuable for understanding our distant ancestors.
Using advanced micro-CT scanning technology and detailed morphological analyses, Zanolli and his team examined the shape and internal structure of the teeth. Their research showed that the teeth from Fontana Fanuccio and Visogliano share several key features with Neanderthal teeth. This includes similarities in the arrangement of the tooth tissues and overall morphology, distinguishing them from modern human teeth, which have different structural characteristics. This was a critical finding, as it adds further support to the theory that Neanderthals had begun to evolve their distinct dental characteristics at a relatively early stage.
What makes these findings particularly significant is their implication for the broader narrative of human evolution during the Middle Pleistocene. The fossilized teeth found in Italy, being so old, are part of a select group of human remains from this period in Europe, providing invaluable insights into the lives of early humans. There has been ongoing debate in the scientific community regarding the identities and relationships of human populations living during the Middle Pleistocene. Some researchers have argued that the period was marked by complex interactions between different human species, with several groups coexisting and possibly interbreeding. This new evidence of Neanderthal-like dental features at such an early date supports the idea that Neanderthals were already evolving distinct characteristics separate from our own species by the Early-Middle Pleistocene transition, around 450,000 years ago.
In particular, the discovery raises important questions about the diversity of human lineages in Eurasia during this time. The teeth from the Italian sites are markedly different from those found in other regions of Eurasia from the same period, suggesting that multiple human populations may have been present across the continent. This supports the idea that the Middle Pleistocene was not a simple time of linear human evolution, but rather one of multiple, distinct human lineages, each evolving their own unique traits.
Zanolli’s team also noted that the dental remains from Fontana Fanuccio and Visogliano share similarities with those found at the famous Atapuerca Sima de los Huesos site in Spain. This site, which is known for its well-preserved fossils, dates back to around the same period, and the dental features from these sites show strikingly similar characteristics. The comparison between the Italian and Spanish fossils further strengthens the hypothesis that the evolution of Neanderthal dental features was occurring across a broad region of Western Europe during this time. As Zanolli explains, “The remains from Fontana Ranuccio and Visogliano represent among the oldest human fossil remains testifying to a peopling phase of the Italian Peninsula. 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 Neanderthal morphological dental template was preconfigured in Western Europe at least 430 to 450 ka ago.”
The study of these fossil teeth provides valuable insights into the social, cultural, and environmental conditions faced by early human populations. Teeth are highly durable and contain a wealth of information about diet, health, and development. The structure and wear patterns of the teeth from Fontana Fanuccio and Visogliano can tell us about the types of food early humans consumed, the environments they inhabited, and how they interacted with their surroundings. This kind of information is essential for reconstructing the lives of early humans, who left behind only limited and often fragmentary remains.
These findings also underscore the growing recognition that human evolution was not a straightforward process of gradual development from one species to another. Instead, it appears that multiple human populations coexisted, interacted, and evolved in parallel over long periods of time. The discovery of Neanderthal-like dental features in these Italian fossils pushes back the timeline for the evolution of Neanderthal traits, suggesting that the evolutionary path leading to Neanderthals was complex and occurred over a much longer period than previously thought.
As more fossils are uncovered and more advanced techniques are developed, scientists are increasingly able to piece together a more detailed and accurate picture of early human evolution. The discovery of Neanderthal-like teeth in Italy is just one example of how ongoing research is revealing the complexity of the human story. The Middle Pleistocene, once thought to be a period of relative simplicity in human evolution, is now recognized as a time of great diversity and change, with multiple human lineages adapting to different environments and evolving unique traits.
More information: Zanolli C, Martinón-Torres M, Bernardini F, Boschian G, Coppa A, Dreossi D, et al. (2018) The Middle Pleistocene (MIS 12) human dental remains from Fontana Ranuccio (Latium) and Visogliano (Friuli-Venezia Giulia), Italy. A comparative high resolution endostructural assessment. PLoS ONE 13(10): e0189773. doi.org/10.1371/journal.pone.0189773