The identification of an unknown type of ancient human in Israel was made possible by solving a “bone puzzle” made by 17 fragments of a mandible (lower jaw bone), a molar and a bone of the skull, Dr. Hila May, a physical anthropologist and a lecturer at the Tel Aviv University Faculty of Medicine told The Jerusalem Post.
The remains – which presumably belonged to the same individual who lived some 130,000 years ago, were uncovered during a salvage excavation at the Nesher cement plant near Ramle led by Hebrew University archaeologist Yossi Zaidner. From there, they were taken to the Dan David Center for Human Evolution and Bio-History Research at TAU.
May is an expert in ancient bones, with her academic interests ranging from the evolutionary history of humans to how ancient diseases have evolved to this day.
Recent studies she has co-authored have included discoveries about how ear infections plagued inhabitants of the land of Israel some 15,000 years ago and how a group of hunter-gatherers fixed the broken leg of one of their peers about 35,000 years ago.
Since the beginning, the bones from Nesher Ramle constituted both a puzzle and a riddle.
“Aligning all the fragments together like a puzzle, partially manually, but mostly virtually, we obtained an almost complete mandible, which starting from many small pieces was a very good result,” May said.
The researchers checked the remains using several techniques, including a micro CT scanning at high resolution.
May noted that the general expectation was that the remains had to have belonged to a Homo Sapien – the modern human species, who started to live in the region around 200,000 years ago.
“However, just by looking at bones, we very soon realized that this was not the case,” she added.
The first clue came from the skull fragment, an almost complete right parietal bone.
“Although we only had a fragment of the skull, by completing it virtually we saw it was very low and flat, compared to ours which is tall and round,” May said. “This is a very archaic characteristic. In addition, the skull was very thick, thicker than ours and even of Neanderthals skulls”.
Another element that marked the difference between the skull that the scholars were examining and a modern human skull was the pattern left on the skull by the blood vessels outside of the brain.
“The pattern on our skulls is complex with many arterial branches, but in that case, it was very simple, with only four arterial branches, once again, very archaic,” May noted.
Asked if these features also indicate that those ancient humans had smaller brains or were less intelligent than us, the researcher said that this isn’t the case.
“I would not go there,” she remarked. “For example, culturally we know that these ancient humans produced the same tools that Homo Sapiens manufactured. We cannot say that they were less intelligent or had less capabilities.”
What the bones suggest has more to do with their physical appearance than with any other feature, according to May.
The mandible offered further insights in this perspective.
“We noticed the absence of chin,” May said. “Only Homo Sapiens had chins.”
Very soon, the researchers could affirm with certainty that the remains did not belong to a Homo Sapien.
“However, it is easy to say what something isn’t, it is much more difficult to understand what it actually is,” May said. “Now that we knew what those bones were not, we needed to understand what they were.”
The scholars started to compare the three-dimensional model they had created with other fossils found in Israel and in the rest of the world.
“This allowed us to realize that we had a very unique combination of characteristics because we saw that the skull was more archaic than the mandible: while both were not Homo Sapiens, the skull was more similar to the ones of other ancient homos, such as Homo Erectus, while the mandible was more comparable to that of Neanderthals,” May said.
“This is how we understood that we were talking about a different type of human,” she further said.
Further clarity was offered by the fact that the Nesher Ramle Homo – as the scholars named it – appeared similar to other fossils found in Israeli prehistoric sites, such as the Qessem Cave, dating back to a much earlier period, as early as 400,000 years ago.
“Some of these fossils were already known but nobody could agree about which ancient human they belonged to,” May said. “Experts previously called them ‘archaic Homo Sapiens’ because they did not understand what they were. We didn’t know that someone else was living here alongside the Homo Sapiens.”
“This was the first time we could give them a name and say that they were a large population living in the region between 400,000 and 130,000 years ago.”
Thanks to the connection they managed to establish between the fossils, the researchers could reach yet another conclusion.
“We had something very archaic, dating back to much earlier than Neanderthals,” May said. “At this point, we started to think that we could be talking about the ancestor population of the European Neanderthals.”
This theory represents one of the most revolutionary aspects of the Nesher Ramla discovery.
Up until this new study – which was published as the cover story of the prestigious journal Science last month – Neanderthals had been believed to have originated in Europe, and later reached the area of Israel – the most south location they ever inhabited, as far we know today – some 70,000 years ago.
“Now we are saying that they came from Israel, they were descendants of the Nesher Ramla Homo,” May said.
Searching through the fossils previously uncovered in Israel, the group also found what appear to be fossils from a hybrid population from a later period, around 100,000 years ago, presenting characteristics of both Homo Sapiens and Nesher Ramla Homo, proving that the two populations not only coexisted in the region, but also interbred.
For the future, May said that it is going to be crucial to find more fossils from the relevant periods.
“We want to find more fossils, we are working on it all the time, we want to learn more about this population,” she said. “There is a lot of work to do.”