Old skulls show modern humans failed in early attempts to colonize Africa

The skull (right), known as Apidima 2, is approximately 170,000 years old and may be part of Neanderthal ancestry. The colorful skull (left) is a virtual reconstruction of it. Copyright Katerina Harvati/Eberhard Karls University of Tübingen)

A prehistoric fractured skull reveals the secrets of ancient humans, a new study finds that early modern humans left Africa earlier than previously thought Much more.

The skull, found in Eurasia and dating back 210,000 years ago, is the oldest modern human skeleton discovered by anthropologists outside Africa, researchers said.

The skull has an unusual neighbor: a 170,000-year-old skull, possibly that of a Neanderthal, was found next to it in a cave in southern Greece. Considering that the Neanderthal skull is 40,000 years younger than that of modern humans, it appears that this particular hominin's early dispersal from Africa failed. Researchers say there are no living descendants of the mysterious hominin, who was replaced by Neanderthals who later lived in the same cave. [Photos: A man wearing a bun and the ancient face of a Neanderthal woman are seen]

"We know from genetic evidence that all humans living outside Africa today can be traced back to Their ancestors were the main spread from Africa that occurred between 70,000 and 50,000 years ago, Katerina Havarti, professor of paleoanthropology at the University of Tübingen in Germany and leader of the research, said at a press conference "Other early modern humans dispersing from Africa have been documented at sites in Israel, one of which is based on the discovery of a modern human jaw that dates from 194,000 to 177,000 years ago," Shang told reporters. " from Misliya Cave and other caves associated with early human fossils from 130,000 to 90,000 years ago. But we think these early immigrants did not actually prepare for modern humans living outside Africa today," Havarti said. Humans contributed, but became extinct, possibly replaced locally by Neanderthals. "We hypothesize that this is similar to the situation in the Apidima 1 population, the latest modern human skull.

This is the oldest known modern human skull in Eurasia, dating to about 210,000 years ago. In Here you can see part of the skull (right), its virtual reconstruction (middle) and a virtual side view. (Copyright Katerina Harvati/Eberhard Karls University of Tübingen) The two ancient skulls discovered in Greece by the "KDSP" were discovered in Athens. Researchers at the University Museum of Anthropology unearthed the skulls in the late 1970s, naming them Apidima 1 and Apidima 2, given that they were found in the Apidima Cave.

Neither skull had a lower jaw and were found side by side in a block of breccia, which are fragments of rock that have stuck together over time. Neither was good; the damaged Apidima 1 only included the back of the skull, and at the time, researchers weren't sure what species it came from. Apidima 2, which preserved the facial area of ??the skull, was identified as Neanderthal, but it was damaged and distorted.

For many years the skulls were kept in the Museum of Anthropology in Athens until the late 1990s and early 2000s, when they were finally cleaned and prepared from the breccia block, Hava Tee and her colleagues placed both skulls in a CT scanner, which produced a 3D virtual reconstruction of each specimen. They then analyzed the characteristics of each one, as before. Analyzing the same, the team concluded that Apidima 2, which had a thick, rounded brow ridge, came from an early Neanderthal, making it more challenging to identify due to the presence of fragmentary fragments of Apidima 1, but the researchers were able to create it. Mirror images of the left and right sides, allowing for a more complete reconstruction of them [In Photos: The oldest Homo sapiens fossil ever discovered]

Several clues, such as the rounded back of the skull (unique to modern humans). features), the researchers said, indicating that Apidima 1 was an early modern human, or Homo sapiens. Next, the researchers dated the skulls, which they estimated were from roughly the same period. Being next to each other suggests that they lived in the same time period, but using a method called uranium series dating, the new team found that the skulls were not from the same time period. Years ago, the Neanderthal skull matched the range of other Neanderthal remains found in other parts of Europe, but the researchers found that the modern human skull was an unexpected outlier, older than the next generation of European intelligence. Human remains are 150,000 years older. Larry Edwards said:

Uranium series dating is one of the only methods available to date such ancient bones, but it has some drawbacks, Minnesota Regents Professor in the University's Department of Earth and Environmental Sciences, who was not involved in the study.

Actually works because uranium decays into thorium. The more thorium there is in a sample, the older it is, Edwards told Live Science. However, bones and teeth themselves do not contain much uranium; instead, they absorb uranium from the environment over time. "This requires you to come up with an explanation of how the uranium was extracted, when it was extracted, and whether the uranium was lost," he said. Although this technique is not suitable for dating skulls such as Apidima 1 and 2, it can still be used. Providing useful data, Edwards said, "I think it's pretty solid," and their (chronological) conclusions, he said, mean outside Africa, though The skull has been called "the oldest known modern human fossil in Eurasia," but the new discovery does not rewrite the fundamentals of human evolution, says Eleanor Skray, Max Planck's Human History in Jena, Germany Associate Professor and leader of the Pan-African Evolutionary Research Group at the Institute of Science, WHO was not involved in the study.

The rationale is that humans first evolved in Africa and then ventured into other parts of the world.

"The oldest human fossils still from Africa predate the Apidima fossils by about 100,000 years," Scerri told Live Science in an email. That's about 4,000 generations — plenty of opportunity for migration.

That is, "if we want to ask some questions about the early history of our species in Eurasia, this study might corroborate arguments for multiple early dispersals," Scerri said. Additionally, the discovery supports the idea that "early Homo sapiens were fragmented and dispersed," she said. [Top 10 Mysteries of Humanity]

Previous research shows that "human beings left Africa every time the Sahara and *** deserts shrunk, which happened roughly within a 100,000-year cycle. ," she noted, which roughly coincides with the date of this study.

What's more, she said, if modern humans actually arrived in Eurasia at least 210,000 years ago, then "we can no longer assume that 'Muslims' were found across large areas of Eurasia. The unique 'stone tool assemblage must have been made by Neanderthals,'"

There are many avenues available to researchers hoping to learn more about the Apidima skull. For example, the skulls may contain ancient DNA or primitive proteins that could confirm their species, writes Eric Delson in an article published online today (July 10) in the journal Nature , who was not involved in this study. Delson is professor and chair of the Department of Anthropology at Lehman College and the Graduate Center of the City University of New York.

Additionally, researchers can study the cave's paleoenvironment and climate to find out what it was like when Apidima 1 and 2 lived there. Today, the cave is located on a cliff facing the sea and is only accessible by boat, Havarti said.

This study is