The Centro Nacional de Investigación sobre la Evolución Humana (CENIEH) is participating in an international study, led by Gabriele Russo, from the Senckenberg Centre for Human Evolution and Palaeoenvironment at the University of Tübingen, Germany, which has re-examined historical fossil collections from the Lebanese sites of Ras el-Kelb, Nahr Ibrahim and Naame. CENIEH researchers Mathieu Duval and Altug Hasözbek, together with Virginia Martinez-Pillado, now a researcher at Ruhr University Bochum in Germany, contributed to the geochronological framework that placed the ecological and behavioral evidence in time.

The results, presented in two complementary papers published in Communications Earth & Environment, a Nature Portfolio journal, show that the central Levant was not merely an ecological extension of the better-studied southern Levant. Along the Lebanese Mediterranean coast, productive woodlands dominated by C3 vegetation, mainly trees, shrubs and grasses typical of temperate climates, and mixed habitats persisted for extended periods, providing relatively reliable water, vegetation and prey despite major glacial-interglacial climatic oscillations. “This environmental stability may have made the coastal zone a recurrent ecological refugium and a favorable corridor for hominin occupation and dispersal,” the authors note.

Geochronology Laboratories

Establishing a reliable chronology was essential because the collections were excavated decades or even more than a century ago and, in some cases, lacked secure stratigraphic information. Therefore, five fossil teeth from the three Lebanese sites were selected for combined uranium-series and electron spin resonance (U-series/ESR) dating at CENIEH’s Geochronology Laboratories, which provide facilities unique in Spain.

“For the first time, it has been possible to place these Lebanese localities reliably within the Middle and Late Pleistocene, indicating ages between 100,000 and 400,000 years,” the authors state.

Woodland resilience and hominin subsistence

The first paper integrates the new chronological framework with zooarchaeology, taphonomy, dental-wear analysis and landscape modeling. Together, the three collections provide one of the longest palaeoecological records available for the region, spanning roughly 100,000 to 400,000 years ago.

The results indicate that Mediterranean woodland ecosystems remained productive along the central Levantine coast and supported diverse ungulate communities, including aurochs, Persian fallow deer, red deer, wild goats and rhinoceroses.

Evidence such as cut marks and impact marks, as well as intentionally broken long bones, indicates that hominins processed animal carcasses at several sites. The combined ecological evidence suggests flexible, seasonally structured hunting strategies and landscape use in woodlands and coastal ecotones, rather than a single uniform subsistence strategy across the Levant.

Long-term ecological stability

The second paper builds directly on this chronological framework, spanning 100,000 to 400,000 years ago, and analyzes bulk and sequential carbon- and oxygen-isotope compositions in herbivore tooth enamel. The study includes eight herbivore species from the same Lebanese collections and reconstructs vegetation structure, hydrology and seasonal temperature regimes.

Across the intervals studied, the isotope data show persistent Mediterranean seasonality, with relatively regular summer-winter contrasts and limited long-term change in seasonal amplitude despite major global climatic oscillations. The animals relied on C3 vegetation within a heterogeneous mosaic of woodland, riparian environments and more open habitats. In this context, the Lebanese coast appears to have provided comparatively predictable ecological resources for nearly 300,000 years.

Why historical collections matter?

The work also highlights the ongoing scientific value of museum collections. Political and social instability has repeatedly restricted field access in Lebanon, and many of the original archaeological contexts have been altered or are no longer accessible.

“By combining direct dating with modern zooarchaeological, isotopic and palaeolandscape modeling methods, historical collections can yield information that was not obtainable when the material was first excavated,” the authors explain.

At the same time, the studies explicitly acknowledge the limitations of legacy collections, including recovery bias, time-averaging and incomplete stratigraphic documentation. Therefore, as the authors explain, “the CENIEH chronology is not merely a dating contribution: it is a key control for identifying mixed-age material and for defining the temporal scale at which ecological and behavioral interpretations are reliable.”

Research framework

This research forms part of the REVIVE project, funded by a European Research Council (ERC) Consolidator Grant awarded to Sireen El Zaatari under the European Union’s Horizon 2020 research and innovation program (grant agreement 101001889). The REVIVE project is carried out in close coordination and collaboration with the Lebanese Directorate General of Antiquities.