Millennia of Mediterranean diet. A meta-analysis of stable isotope data and new insights

Later Prehistory represents the starting point for the development of Mediterranean cultures as we know them today. With the spread of agriculture, human subsistence practices started shifting, together with the equilibrium between individuals and the surrounding environment. A focal point of these millennia is food, and how dietary choices tie to cultural shifts and social organisations in every corner of the Mediterranean. This thesis focuses on stable isotope analysis for the reconstruction of dietary practices in the Mediterranean Basin from the Neolithic to the Iron Age (ca. 6000 - 600 BCE). First, a dataset collating previously published human, animal and plant isotopic data has been developed. This dataset, the Mediterranean Archive of Isotopic dAta (MAIA), is made available in open access for researchers to use and has been employed to study collagen preservation patterns. Data gaps in the isotopic literature have also been identified, specifically the lack of data for Northern Africa and the very low presence of plant isotopic measurements. Employing MAIA, a meta-analysis for the reconstruction of subsistence patterns in Italy has been conducted. Spatiotemporal similarities and differences across the Peninsula have been identified through the application of Bayesian statistics as well. A homogenous terrestrial diet is observed, with a balanced consumption of animal and plant products. The apparent lack of aquatic resource consumption by prehistoric humans is consistent with previous interpretations of bulk stable isotope analysis applied to skeletal remains from the Mediterranean region, either because of a sporadic consumption - which would not be visible through bulk stable isotopes, as collagen molecules provides an average dietary signal over several years of life - or because of the local ecology of the Mediterranean Sea - as the isotopic signal of marine resources is often similar to that of terrestrial animals. Shifting from a population-level approach to a high-resolution one, single amino acids have been applied to two southern Italian populations from the Bronze Age, Coppa Nevigata and Toppo Daguzzo. This high-resolution approach shows diversity within the homogeneous terrestrial diet previously observed through bulk stable isotope analysis, highlighting dietary choices adapted to the surrounding environment. Overall, when analysing the prehistoric isoscape of the Mediterranean - both at a broad scale and through a more detailed examination of ancient diets in Italy - it becomes evident that isotope data play a crucial role in advancing our understanding of Later Prehistory in the Old World. The extensive and high-quality isotope data accumulated over the past decades of dedicated research have enabled a systematic reassessment of dietary practices, reaffirming, to some extent, the profound impact of farming on prehistoric communities. However, a more nuanced analysis has also revealed previously unrecognised patterns of change and complexity, challenging earlier assumptions.