Earliest Mediterranean long-distance sea journeys were sustained over at least a millennium

The discovery that remote Mediterranean islands were colonized before the invention of agriculture has upended long-standing views about the maritime capabilities of Europe’s last hunter-gatherers. New evidence from Malta now shows that these hunter-gatherers were engaging in repeated long-distance sea journeys of at least 100 kilometers (km), likely between Sicily and Malta for at least a millennium.

To the point:

• Population limits: Malta’s small size could only support a limited hunter-gatherer population, too small for long-term survival without outside contact.
• Sustained presence: Archaeological evidence shows continuous hunter-gatherer occupation on Malta from about 8400 to 7400 years ago.
• Social networks: Survival over centuries required connection to larger populations, implying ongoing overseas sea travel and social exchange.

A new study, published this week in PNAS Nexus and led by Dr Jimbob Blinkhorn of the University of Liverpool with Professor Eleanor Scerri of the Max Planck Institute Geoanthropology and colleagues from the University of Malta and University of Cambridge, shows that the Maltese Islands were too small to sustain a hunter-gatherer population large enough to survive in isolation for centuries. The continuous presence of hunter-gatherers in Malta for a millennium can only be explained if the occupation was supported by overseas social networks underpinned by repeated long-distance sea voyaging.

“The ability to engage in long-distance seafaring marks a major transition in human history, in which previously impassable maritime barriers became the frontiers of new connections. In the Mediterranean, single-stage, long-distance open-water sea voyaging is first documented in the Mesolithic.” Explains Prof. Eleanor Scerri, a senior author on the study. “On Malta, we documented a continuous Mesolithic presence from at least 8400 to 7400 years ago. Was this an accidental stranding, however, or is it representative of a previously unknown seagoing network?”

A Limit for Resources and Population Size

To answer the question, the research team, led by the University of Liverpool’s Computational Archaeology of the Stone Age group, combined insights from modern ethnography with palaeoclimate data and sea-level models to examine likely hunter-gatherer population sizes and long-term survival possibilities.

“Unlike farmers, hunter-gatherers are dependent on wild, natural food resources, whose abundance is largely governed by the climate for a given area, with larger areas and more productive environments able to support larger populations” says Dr Jimbob Blinkhorn, the lead author of the study, “By modelling the relationship between modern hunter-gatherer population sizes and their environment, we were able to predict potential past population sizes using high-resolution palaeoclimate datasets. While Malta was once connected to Sicily via a land-bridge, this was inundated by around 14 thousand years ago, cutting Malta off and limiting the land area to support hunter-gatherer populations.”

The study’s estimates showed that the maximum possible population size Malta could have supported after its isolation from Sicily ranged between 170-144 individuals, with more realistic, ethnographic-derived predictions estimating a considerably smaller population. This low population density prediction spans the 1000-year timeframe that recent archaeological discoveries document hunter-gatherer occupation of Malta

Evidence of Unknown Networks

“Long-term survival of a population, such as over a millennium evident in the archaeological record, would require 500-1000 reproductive-age adults, before we include the young and the elderly,” explains Dr Blinkhorn. “Given that we predict far smaller population sizes in Malta, these hunter-gatherers must have been connected to a wider gene pool to prevent inbreeding and collapse – the only way this would be possible is through repeated, overseas connections.”

“Our study proves that Malta was part of a hitherto unknown, sustained, long-distance sea voyaging network”, add Professor Scerri, “The last European hunter-gatherers were not only reconfiguring the use of land and sea in a way that preempts the modern world, they were also maintaining social networks in ways we don’t see before, connecting islands and coastlines, perhaps even across continents.”

Dr Blinkhorn is supported by a University of Liverpool University Research Fellowship. The research was funded by a European Research Council Grant awarded to Prof Scerri