Giuseppe Briatico

Enamel hypoplasia results from temporary disruptions of enamel deposition during tooth development. It is widely used as an indicator of physiological stress in archeological and paleontological contexts; yet, its relationship with environmental conditions during tooth formation remains poorly constrained. Here, we combine macroscopic identification of linear enamel hypoplasia (LEH) with intra‐tooth stable carbon ( δ ¹³ C) and oxygen ( δ ¹⁸ O) isotope records from 100 sequential enamel samples to investigate short‐term environmental variability and physiological stress in Early Pleistocene hippopotamids from Melka Kunture (Upper Awash Valley, Ethiopia). Two continuously growing teeth (specimen IDs MK 18 SIMB III 128 and MK 75 GOM II 672), respectively dated to ~1.4 and ~1.0 Ma, were selected because they were the only specimens in the examined assemblages in which LEH was identified. Although both teeth show LEH, they show different distributions of the enamel defects and contrasting intra‐tooth isotopic patterns. MK 18 SIMB III 128 (~1.4 Ma) displays a broad intra‐tooth variation and a strong positive cross‐correlation between its δ ¹³ C and δ ¹⁸ O profiles. The enamel within the LEH‐affected interval has higher δ ¹³ C and δ ¹⁸ O values than the unaffected apical enamel, and samples positioned directly on visible LEH differ from adjacent enamel in both isotope systems. These patterns are consistent with discrete stress episodes associated with changing hydrological conditions, although dietary and physiological contributions to the carbon isotope record cannot be separated. MK 75 GOM II 672 (~1.0 Ma) displays narrower isotopic variation and LEH across most of the preserved tooth surface. Its profile is compatible with prolonged or recurrent stress under relatively stable, water‐limited hydrological conditions, but the localized isotopic differences do not identify a single causal mechanism. The differences between the specimens may reflect both their distinct developmental histories and local variation in fluvial dynamics and water‐source stability. Because enamel mineralization and sampling integrate isotopic information over extended developmental intervals, the observed associations should be interpreted at the scale of broader developmental phases and not as evidence of exact synchrony between LEH formation and individual isotope values. The integration of LEH and intra‐tooth isotope analysis provides a promising framework for investigating relationships among individual life histories, physiological stress, and environmental variability in fossil mammals.

Climate variability is a key factor influencing the distribution and adaptive response of mammalian species, including hominins. Here, we investigate seasonal and interannual hydroclimatic and environmental variability associated with the late Early Pleistocene hominin occupations on the Southeastern Ethiopian Highlands. We present stable carbon and oxygen isotope analyses of sequentially sampled tooth enamel from herbivores recovered from the archaeological contexts of Melka Wakena and Gadeb (2300-2400 m a.s.l.) and dated between 1.6 and ~ 1.0 Ma. Carbon isotope data indicate predominantly C₄ and mixed C₃-C₄ diets, consistent with mosaic vegetation as part of the Dry evergreen Afromontane Forest and grassland complex (DAF). Intra-tooth oxygen isotope profiles suggest seasonal variability and interannual fluctuations in water balance, reflecting changes in precipitation, evaporation, and local hydrology. Although the temporal resolution of individual tooth records precludes identification of specific climatic drivers, the isotopic data document recurring hydroclimatic variability within high-elevation environments characterized by broadly comparable ecological conditions. Herbivore diets show limited long-term change, suggesting sustained resource availability across seasons and over hundreds of thousands of years. These results indicate that the Ethiopian Highlands repeatedly supported mammalian communities and recurrent Acheulean hominin occupations during the late Early Pleistocene, providing sustained access to water and vegetation resources within an Afromontane environmental framework.

The eastern African archaeological record is central to understanding early human evolution, yet its Pleistocene sites often present major challenges for public interpretation due to their open-air character and limited monumentality. In this context, in situ musealisation has emerged as a key strategy for combining conservation, research, and public access. This paper examines the historical development of such practices in eastern African archaeology through a comparative assessment of major sites, including Olorgesailie, Kariandusi, Isimila, and Olduvai Gorge, with particular emphasis on the Melka Kunture and Balchit (Ethiopia) archaeological complex. The analysis shows that early initiatives were largely experimental, frequently linked to specific academic events or tourism development, and commonly based on the direct exposure of archaeological surfaces, which generated important conservation and research constraints. By contrast, Melka Kunture represents a more integrated management model that combines landscape-scale interpretation, controlled visitor itineraries, multilingual outreach, high-resolution documentation, and the strategic use of replicas in a sensitive context. Recently inscribed on the UNESCO World Heritage List, the site illustrates how Pleistocene heritage can be made publicly accessible without compromising scientific integrity.

Beefa Cave is a site that is part of the Melka Kunture archaeological complex located in the Ethiopian Highlands in the upper Awash River Valley. Excavations have revealed a sequence of ashy levels dating to the mid-Holocene. Lithic artifacts, faunal remains, undiagnostic pottery, and micro- and macrobotanical remains were recovered. The lithic assemblage of Beefa Cave is analyzed here using a techno-typological approach, combined with use-wear and residue analysis, and results are further contextualized with archaeobotanical and archaeozoological data. Preliminary results provide initial insights into the occupation of the cave, establishing a starting point for studying Holocene settlement and economy on a regional basis and from a diachronic perspective.

Pleistocene environments are among the most studied issues in paleoecology and human evolution research in eastern Africa. Many data have been recorded from archaeological sites located at low and medium elevations (≤ 1500 m), whereas few contexts are known at 2000 m and above. Here, we present a substantial isotopic study from Melka Kunture, a complex of prehistoric sites located at 2000—2200 m above sea level in the central Ethiopian highlands. We analyzed the stable carbon and oxygen isotopic composition of 308 faunal tooth enamel samples from sites dated between 2.02 and 0.6 Ma to investigate the animal diets and habitats. The carbon isotopic results indicate that the analyzed taxa had C₄-dominated and mixed C₃-C₄ diets with no significant diachronic changes in feeding behavior with time. This is consistent with faunal and phytolith analyses, which suggested environments characterized by open grasslands (with both C₃ and C₄ grasses), patches of bushes and thickets, and aquatic vegetation. However, palynological data previously documented mountain forests, woodlands, and high-elevation grasslands. Additionally, the carbon isotopic comparison with other eastern African localities shows that differences in elevation did not influence animal feeding strategies and habitat partitioning, even though plant species vary according to altitudinal gradients. In contrast, the oxygen isotopic comparison suggests significant differences consistent with the altitude effect. Our approach allows us to detect diverse aspects of animal behavior, habitat, and vegetation that should be considered when reconstructing past environments.

In this paper, we present stable carbon and oxygen isotope analyses of fauna tooth enamel from Garba IVD (1.95 Ma) and Gombore IB (1.66 Ma), two Early Acheulean sites of Melka Kunture (Upper Awash, Ethiopia), and discuss faunal taxonomy and fossil pollen. Our aim is to infer the diet and habitat of the fossil fauna, as well as the environment of both sites, in order to provide a broader paleoecological reconstruction. During the Pleistocene, the vegetation of the highlands of Ethiopia belonged to the Dry evergreen Afromontane Forest and grassland complex, which is distinct from the savanna of lower elevations in eastern Africa. Our carbon isotopic results indicate that all the analyzed faunal taxa were grazers consuming C₄ plants, whereas oxygen isotopic results discriminate the taxa according to their semiaquatic or terrestrial habitats. These results are consistent with the taxonomic composition of the faunal assemblages and the palynological results, suggesting extended mountain grasslands in the landscape at Garba IVD. In contrast, the carbon isotopic results do not totally agree with the pollen paleoenvironmental reconstruction at Gombore IB, where the open vegetation was interrupted by forests and bushy vegetation. Stable isotope and pollen data provide different outcomes (feeding strategies vs. nearby plants) and have different temporal and spatial resolutions. This is relevant when reconstructing past environments by using independent proxies. Furthermore, isotopic comparisons with other Early Pleistocene paleontological and archaeological sites from eastern Africa indicate that all the analyzed taxa in common fed on C₄ plants and that their dietary strategies were not affected by variations linked to the difference in elevations.