A recent discovery of an ancient submerged bridge in the Genovesa cave on Mallorca, a Spanish island in the western Mediterranean, has led to significant changes in our understanding of early human activity in this region. The research team led by a geology professor from the University of South Florida, Bogdan Onac, has uncovered evidence suggesting that humans settled on Mallorca much earlier than previously thought, pushing back the start of human colonization of the island by more than two thousand years.

Bridge as a key evidence of early human presence
The discovered bridge, built from large limestone blocks, is located within a flooded cave and extends over a length of 7.6 meters. By analyzing the mineral deposits that formed on the bridge, researchers have determined that it was constructed nearly 6,000 years ago, which is significantly earlier than previous estimates. This analysis included studying the light-colored deposits on the upper part of the bridge, which resulted from changes in sea level and the deposition of calcite layers over millennia.

Historical context and significance of the discovery
Although Mallorca is one of the largest islands in the Mediterranean, it was among the last to be colonized. While islands like Cyprus and Crete were settled as early as 9,000 years ago, newer evidence, such as this bridge discovery, suggests that human activity on Mallorca began much earlier than previously believed. Previous studies placed the first human traces on the island at around 4,400 years ago, but this discovery pushes that date back by an additional 1,600 years. These findings align with the timeline of settlement between the eastern and western Mediterranean, indicating the existence of a continuous expansion of human civilization across this area.

Research methods and future studies
The research team used sophisticated dating techniques and underwater explorations to reach these conclusions. Periods of high sea levels left traces on the bridge, allowing for precise dating of the structure. This discovery highlights the importance of interdisciplinary collaboration, as geologists, archaeologists, and other experts worked together to reconstruct historical events. Onac plans to continue investigating other cave systems, some of which contain deposits millions of years old, with the goal of identifying pre-industrial sea levels and exploring the impact of modern global warming on sea level rise.

Impact on future research and heritage protection
This discovery has far-reaching implications not only for understanding the history of human migration and settlement but also for future research in the field of underwater archaeology. Given the increasing threat of sea level rise due to climate change, similar submerged structures could provide crucial information on how our ancestors adapted to changing environmental conditions. At the same time, it underscores the urgency of protecting coastal archaeological sites that may hold even more secrets about our past.

The research was funded by several grants from the National Science Foundation and conducted in collaboration with Harvard University, the University of New Mexico, and the University of the Balearic Islands.

Source: University of South Florida