Secret of human evolution may be hidden inside 400,000-year-old skull!

Image courtesy: Javier Trueba

New Delhi: Human evolution is an intriguing subject and has long since been a point of interest for scientists, who have delved deeper into it than anyone else to figure out the nuances behind it.

Six million years – that's how long it took us to evolve from the form of our ape-like ancestors to what we are now and there are still many secrets that scientists are trying to decode.

Now, in an interesting find, scientists have come across a part of a skull dating back to 400,000 years – the oldest human cranium ever found in Portugal – marking an important contribution to the knowledge of how our race evolved.

The cranium represents the westernmost human fossil ever found in Europe during the middle Pleistocene epoch and one of the earliest on this continent to be associated with the Acheulean stone tool industry.

In contrast to other fossils from this same time period, many of which are poorly dated or lack a clear archaeological context, the cranium discovered in the cave of Aroeira in Portugal is well-dated to 400,000 years ago and appeared in association with abundant faunal remains and stone tools, including numerous bifaces (handaxes).

"This is an interesting new fossil discovery from the Iberian Peninsula, a crucial region for understanding the origin and evolution of the Neanderthals," said Rolf Quam, an associate professor at Binghamton University in the US.

"The Aroeira cranium is the oldest human fossil ever found in Portugal and shares some features with other fossils from this same time period in Spain, France and Italy," said Quam.

"The Aroeria cranium increases the anatomical diversity in the human fossil record from this time period, suggesting different populations showed somewhat different combinations of features," he said.

The cranium was found in 2014. Since the sediments containing the cranium at the Aroeira site were firmly cemented, the cranium was removed from the site in a large, solid block.

It was then transported to the restoration laboratory Spain, for preparation and extraction, a painstaking process which took two years.

The new fossil will form the centerpiece of an exhibit on human evolution in October at the Museu Nacional de Arqueologia in Lisbon, Portugal.

The study appears in the journal PNAS.

(With PTI inputs)