A crucial piece of the story of humankind’s exodus from Africa was recently found near the northern Israeli city of Nahariya — a 55,000-year-old skull of an anatomically modern human, among the first to leave the cradle of humanity and populate the globe.

Scientists from Tel Aviv University, Ben-Gurion University and the Israel Antiquities Authority who found and studied the fossilized skull said the rare find was a “connecting link” between Homo sapiens worldwide and the core population that left the cradle of humanity around 60,000 years ago and began replacing other hominin species.

A paper detailing their findings was published Wednesday in the scholarly journal Nature.

“It’s a key piece in the puzzle of human evolution,” Dr. Israel Hershkovitz, one of the authors of the paper involved in the excavation of the Manot Cave, the site of the find, said ahead of the publication. “This is one of the most important missing pieces because it allows you to connect the African hominids with the European hominids.”

The skull was among a trove of Paleolithic remains found in a limestone cave in the Western Galilee town of Manot, which was discovered in 2008 when a bulldozer breached a hole in the cavern’s ceiling. During subsequent excavations in 2010, archaeologists found the dome of a human skull the size of a soup bowl.

Closer examination proved that it was an anatomically modern human’s, and included an “archaic” protrusion at the base of the neck typical of modern African and European skulls, and that Manot people “could be closely related to the first modern humans who later successfully colonized Europe.”

A skull fragment found in the Manot Cave (left) alongside modern human (center) and Neanderthal skulls (photo credit: Judah Ari Gross/Times of Israel staff)

A skull fragment found in the Manot Cave (left) alongside modern human (center) and Neanderthal skulls (photo credit: Judah Ari Gross/Times of Israel staff)

“There was some slight difference in the brain structure,” Hershkovitz said. “But you can’t automatically correlate it with mental capacity or intelligence. What it means, what it tells you, you don’t know.”

The skull is covered in a brown patina after having been buried for several dozen millennia. A sophisticated uranium-thorium dating method of patina samples determined that the skull was between 50,000 and 60,000 years old.

Earlier hominid species left Africa hundreds of thousands of years before the evolution of Homo sapiens, and indeed early humans branched out into Europe and Asia in waves around 100,000 years ago.

Dr. Omry Barzilai of the Israel Antiquities Authority near the site of an ancient skull fragment's discovery in the Manot Cave (photo credit: Judah Ari Gross/Times of Israel staff)

Dr. Omry Barzilai of the Israel Antiquities Authority near the site of an ancient skull fragment’s discovery in the Manot Cave (photo credit: Judah Ari Gross/Times of Israel staff)

Those populations went extinct, Hershkovitz explained, and we’re not descended from them. Genetic analysis indicated that today’s human population comes from wanderers who left Africa around 60,000 years ago and began interbreeding with Neanderthals.

He noted that roughly four percent of all modern humans’ DNA is Neanderthal, because our ancestors interbred with the extant homonin population. Genetic models indicate that the first hybridization took place between 50,000 and 60,000 years ago in the Levant.

“Manot, in terms of time and location,” he said, “is the best candidate for the love story that scientists talk about between Neanderthals and Homo sapiens.”

The Manot Cave is one of a constellation of Paleolithic sites dotting Israel’s Galilean coastline. Its interior, warm and humid, is resplendent with stalactites and stalagmites, and the soft soil of the floor has yielded an enormous quantity of animal remains.

Bone fragments belonging to an assortment of Paleolithic ungulates found in Manot Cave (photo credit: Judah Ari Gross/Times of Israel staff)

Bone fragments belonging to an assortment of Paleolithic ungulates found in Manot Cave (photo credit: Judah Ari Gross/Times of Israel staff)

Dr. Ofer Marder, an anthropologist at Ben-Gurion, was among the first to enter the cave in 2008, which he described as a “time capsule” from the Paleolithic era whose entrance was sealed shut by an earthquake about 13,000 years ago.

Most of the remains found in the cave — stone and bone tools, fragments of deer, gazelle and hyena bones and human skeletal fragments — range from 45,000 to 20,000 years old. They demonstrate that the limestone shelter, and the woodland surrounding it, was intensively occupied by both humans and wildlife during the Paleolithic.

Scientists aren’t sure whether the skull belonged to a man or a woman, or how it ended up in the cave. Although humans had already begun burying their dead, there was nothing to suggest that was the case. Reuven Yeshurun, a paleozoologist at the University of Haifa who examined bone fragments found in the Manot Cave, suggested the human skull could have been brought in by a hyena, as there were other bones incised with tooth marks.

Excavations at Manot were ongoing and could yield additional human remains. Marder speculated that the skeleton whose skull they found in 2010 could still be in the cave: “Maybe it’s waiting for us.”