A high-resolution paleoenvironmental record based on phytoliths from the Armenian Highlands: The Upper Paleolithic of Aghitu-3 Cave

The rich archaeological record of the Late Pleistocene in the southern Caucasus and Armenian Highlands offers archaeologists a unique opportunity to study the behavioral patterns of the varied groups of hominins who occupied the region. As choices around subsistence, migration, and social networks, take place within regional and local paleoenvironmental conditions, understanding these is critical to any archaeological interpretation. Building on previous research linking modern vegetation types with distinct phytolith assemblages, this study uses phytoliths as a proxy to examine the Upper Paleolithic paleoenvironment in the northeastern Armenian Highlands. Based on relative abundance and linear discriminant analysis, phytolith assemblages from the archaeological site of Aghitu-3 Cave (40–24 ka) are used to test the hypothesis that modern phytolith data can function as a proxy for paleoenvironmental reconstruction. This particularly well-stratified Upper Paleolithic site is located in southern Armenia. The results of this study show clear differences in vegetation throughout the site’s 16,000-year sequence. These shifts likely represent the expansion and retreat of subalpine woodland and herb-dominated grassland biomes against the dominant steppe environment in the region. Although regional climate data show rapid and intense shifts in climatic conditions through MIS 3 and 2, the phytolith assemblage at Aghitu-3 suggests that local environmental response was muted. Additionally, phytoliths from intensified human occupation deposited in Archaeological Horizon III (∼29–24,000 cal BP) suggest that the inhabitants utilized sedge as raw material, likely for bedding or basketry. This study shows the potential of phytolith analysis for paleoenvironmental reconstruction and beyond, in the southern Caucasus and Armenian Highlands.