Source: National Geographic

In 1996 archaeologists ventured into a cave in Gibraltar, where they found a burial containing human bones. Among them was a skull.

The archaeologists knew that the burial was very old. It was discovered under layers of sediment containing fish, bird, and mammal bones and carved flint objects. The skull had been damaged after the burial, but it still joined the collection of the Gibraltar National Museum.

The skull’s age remained a mystery for many years. In 2019 the results of a landmark study proved through DNA analysis that it belonged to a woman who lived 7,500 years ago, making it the oldest remnant of a modern female woman found in Gibraltar to date.

Analysis also revealed that the skull’s genetic ancestry lay far east of the Iberian Peninsula. The presence of genes from across the Mediterranean gave archaeologists new clues about how ancient humans travelled when agriculture was spreading through Europe.

The Gibraltar National Museum team worked to create a forensic anatomical reconstruction of her face. Computers scanned its broken bones and utilized 3D cloning and restitution programs to recreate missing and damaged portions, including the jaw. Combining the data from the scans with the genetic analysis, a team at the museum spent six months to create her striking, lifelike visage. The model was named Calpeia by researchers, who were inspired by the classical term for Gibraltar, known in ancient times as Mons Calpe.

Rock of humanity

Situated at the southern tip of the Iberian Peninsula, Gibraltar is no stranger to the presence of ancient hominid remains. Numerous exciting discoveries from Gibraltar have shed light on early human history. Gibraltar, British since the 18th century, lies within sight of Morocco across the Strait of Gibraltar at the gateway to the Mediterranean Sea.

Just under 1,400 feet high, the limestone outcrop is riddled with an extensive cave network that has offered shelter to humans, and their hominid cousins, for tens of thousands of years.

Calpeia’s burial was found in a cave at Europa Point, located at the southern-most tip of the peninsula. Nearby lies the Gorham’s Cave Complex, a UNESCO World Heritage site, once home to Gibraltar’s Neanderthal population, who are of special interest to archaeologists. An extinct form of humans, Neanderthals were living in these caves as recently as 32,000 years ago.

Story of the skull

When Calpeia’s skull was found in 1996, it was impossible to glean much information from it. Gibratar’s humid climate leads to a rapid deterioration of DNA, and the possibilities of extracting useful genetic material seemed unlikely at the time. DNA analysis was in its infancy, and the damage to the skull made it difficult to study.

By 2019 the study of ancient DNA had made great strides. The journal Science published the genome analysis of 271 inhabitants of Spain, Gibraltar, and Portugal, including the 1996 skull. Under the coordination of Harvard Medical School, researchers were successfully able to extract viable samples of ancient DNA.

The results told the researchers a great deal: The skull belonged to a woman who lived around 5400 B.C.—many millennia after the Neanderthals of Gibraltar had become extinct. She was slightly built, light-skinned, with dark hair and eyes. She was also lactose intolerant (a common trait for that period).

Dated to 7,500 years ago, Calpeia’s life corresponds to the later Neolithic period. She lived at a time when agriculture and raising livestock were spreading across the Iberian Peninsula, displacing the old hunter-gatherer model. Her lactose intolerance indicates that dairy farming was most likely not part of her culture.

Calpeia’s age when she died cannot be determined precisely from the skull. Her cranial sutures—the fibrous joints connecting the bones of the skull—suggest that she was an adult, somewhere between 25 and 40 years of age.

Head West

Researchers were most excited about what DNA revealed about Calpeia’s ancestry. Only 10 percent of Calpeia’s genome comes from the population found in the Iberian Peninsula, while the remaining 90 percent has its origin in Anatolia, modern-day Turkey. Farmers from Anatolia during the Neolithic period had a high percentage of alleles for dark eyes and light skin. By contrast, hunter-gatherers from central and western Europe show genetic markers for dark skin and light eyes.

Archaeologists believe that agriculture developed in several areas of the world at roughly the same time. Anatolia was one of the global centres of the Neolithic revolution. From there, techniques for crop farming and animal husbandry slowly spread westward across the Mediterranean world and into Europe.

The high proportion of Anatolian components in Calpeia’s DNA suggests that her Anatolian origins were recent. It is likely that Calpeia—or her parents or very recent ancestors—journeyed from Anatolia to Gibraltar by sea.

If Calpeia’s people had travelled by land, their progress westward would have taken years or generations. Their DNA would have mixed with local populations along the way, making Calpeia’s resulting genome more diverse.

Analysis of genes of individuals from the Mediterranean island of Sardinia also finds a high proportion of Anatolian genes, bolstering the theory that Anatolians travelled west over the Mediterranean.

Whether agricultural produce travelled with them has not yet been established. No archaeological evidence indicates agricultural activity at this period in Gibraltar. It is likely that Calpeia and her cohorts hunted and fished.

Even so, archaeologists have uncovered the remains of wheat seeds dating to the same era in which Calpeia lived, around 125 miles away. She lived on Gibraltar at a time of great change in human customs, a transformation that she—or her Anatolian relatives—were doing much to introduce and to spread.

Source: National Geographic