Contextualizing Early to Middle Pleistocene hominin ecology in the Indian Subcontinent

ABSTRACT

The paleoecology of early hominin dispersal(s) out of Africa remains a central topic of discussion in paleoanthropology. While African and Eurasian records are relatively well documented, the Indian Subcontinent has remained underrepresented in this discourse. Here, we present the first multiproxy paleoecological reconstruction of Early‐to‐Middle Pleistocene (2.58–0.4 Ma) environments in the northern Indian Subcontinent, combining dental δ ¹³ C and δ ¹⁸ O isotope analysis, dental mesowear, and dental ecometric trait data from 289 mammalian dental specimens from the Pinjor Formation, Upper Siwalik Hills of northern India. δ ¹³ C values indicate a predominantly C ₄ ‐based herbivore guild throughout the study period, with progressive broadening toward mixed C ₃ –C ₄ diets after ~1.77 Ma. Strong temporal variation in δ ¹⁸ O values indicates that hydroclimatic variability was possibly the primary driver of this ecosystem reorganization across this interval. In conformity to results from the dental enamel, climate estimates based on dental ecometric trait data document a similar transition from drier, open grassland conditions before ~1.77 Ma to a more productive, structurally heterogeneous savannah mosaic ecosystems after ~1.77 Ma. These results demonstrate that the region sustained a predominantly savannah mosaic ecosystem, with an increase in habitat heterogeneity after the Early to Middle Pleistocene Climate Transition, corresponding to an increase in precipitation. This mosaic landscape sustained resource availability and opportunities, critical for survival of hominins dispersing through the region. This study fills a critical geographic gap by adding to the growing body evidence indicating that hominins occupied diverse and regionally variable environments during early out‐of‐Africa dispersal(s).