Underwater caves provide clues that could explain the early expansion of Homo sapiens into Mediterranean islands

Archaeological studies by scientists at Washington University in St. Louis suggest that coastal and underwater cave sites in southern Sicily contain important new clues about the path and fate of early human migrants to the island.

A study in PLOS ONE reports and evaluates the contents of 25 caves and rock shelters, most first identified between 1870 and the 1990s but essentially lost to science over time. The study authors also conducted new land and underwater surveys in previously unexplored coastal areas and discovered three new sites containing potentially important archaeological sediments.

“What we’re looking for is not just the first person to arrive, but the first community,” said Ilaria Patania, assistant professor of archeology in Arts and Sciences. “Understanding the timing of the initial colonization of Sicily provides key data on the pattern and mode of the early expansion of Homo sapiens into the Mediterranean.”

Many researchers consider Sicily to be the first island in the region to be permanently occupied by human ancestors, but it is unclear when and how the first migrants accomplished this feat. Sicily is less than two miles from mainland Italy, but crossing the waters would have been extremely difficult for early humans.

Other studies have primarily focused on possible entry points on the north side of the island.

“This research shows that new ways of thinking and looking can reveal patterns that were not previously visible,” said TR Kidder, the Edward S. and Tedi Macias Professor of Anthropology in Arts and Sciences at WashU, co- author of the new study.

“Previous researchers thought sites on the southern coast of Sicily would be eroded or too damaged to provide useful information,” Kidder said. “But the discovery of underwater sites opens up a whole new area to study. It allows us to reconsider the migration routes of these early modern human ancestors.”

Dangerous water crossing

Sicily, the largest island in the Mediterranean, is located just at the tip of Italy’s boot.

In the ancient Greek poem “The Odyssey,” Homer describes how Odysseus sailed his ship past the mythical sea monsters Scylla and Charybdis as he crossed the Strait of Sicily. The strait was well known to sailors of the past; they attributed the deadly forces of its waves and whirlpools to powerful monsters.

Today, thousands of migrants from North Africa attempt to cross the strait every year. Many do not make it, with some capsizing just a few hundred meters from landing.

Patania, originally from the island of Sicily, has a deep respect for the power of the sea. Her grandfather was a fisherman who worked the same shores she studies today.

“Very early on, I was taught that the sea could be a tremendous resource,” she says. “At the same time, we never turn our back on the sea. The sea can be very dangerous.”

This idea is reflected in his research. “I’m very interested in how humans occupy marginal environments,” Patania said. “These are environments in which, if everything goes well, we are in perfect harmony with nature. But if something changes – and it could be something like global climate change, or something smaller, like the arrival of a new animal – that could be a change. disaster.”

Specialists in the region agree that humans arrived in Sicily 16,000 years after the last glacial maximum. But this established date is surprisingly late, given that humans are known to have dispersed overland to Siberia around 30,000 years earlier. This discrepancy has led some to question whether humans actually arrived in Sicily well before currently accepted dates.

Additionally, no one yet knows whether humans arrived in Sicily by sea or on foot via a land bridge, or even from which direction they came.

“A challenge to understanding the spread of the earliest ancestors of modern humans is that we do not fully understand how they spread and colonized the world at a very early stage,” Kidder said.

“As Ilaria says, this is a very marginal environment. Did people come from Italy and cross the Strait of Messina, or did they come from the south along the African coast? Or is it possible that they travel across the Mediterranean from island to island? Locating sites on the southern coast helps us to think about routes and therefore behaviors.

Eyes on the sea

Patania is leading a long-term research project focused on the earliest occupations of Sicily. “In southeastern Sicily, very few Upper Paleolithic sites have been excavated and analyzed using scientific methods,” she explained.

“Our project is still in its early stages, but we have already identified and assessed more than 40 sites of interest, approximately 17 of which are sites that have been moved more accurately based on older identifications,” he said. said Patania.

She and her team prepared for their recent cave explorations by digging through the archives of Sicily’s municipal libraries, reading historical bulletins and news articles dating back to the 19th century.

Researchers identified potential sites and examined records and photographs of materials recovered by local professional archaeologists. Where possible, they interviewed workers who had participated in previous digs and also spoke with recreational divers and local fishermen.

For example, one of the co-authors of the new study is a retired tugboat captain. He has no formal scientific training, but he spent decades working on boat decks in and around Augusta Harbor.

“The moment I said I was looking for paleosols, and paleosols looked like clay soil that might be red or gray underwater, he said, ‘I know exactly what you’re looking for.’ Patania said.

Patania also partnered with the Superintendent of Cultural and Natural Heritage of Syracuse and Ragusa (two provinces of Sicily) and the Superintendent of the Sea of ​​Sicily to locate and recruit other local experts and stakeholders.

As the research progressed, Patania also spoke with Italian naval officers about training members of their specialized diving team to help them identify underwater archaeological features. These divers spend a lot of time in local waters performing their regular duties related to cleaning up munitions and other debris from World War II.

“We started with the area near the coast and we will gradually move further away in the coming years,” Patania said.

Excavations continue

Two of the new sites of the PLOS ONE The study may contain traces of Upper Paleolithic human occupation, including fossil fauna, the study authors said.

Corruggi is located at the southern tip of Sicily. The site was identified by other researchers in the 1940s.

“It is on this site that a second land bridge would have connected this island to the island of Malta,” Patania explained.

“When we inspected this site, we found European wild ass teeth and stone tools,” she said. “Analyzing the remains from this site could give us insight into the very last stage of the human journey south, to the southernmost coast of Sicily and towards Malta.”

During the summer of 2024, project team members worked to excavate the second site, a cave called Campolato.

“Here we found evidence of sea level changes caused by the last glaciation and a localized earthquake that we are still investigating,” Patania said.

“We hope to reconstruct not only the time of human occupation, but also the environment in which these people lived and how they coped with natural events like earthquakes, climate and environmental changes and perhaps even volcanic eruptions,” she said.