Multiproxy paleoenvironmental reconstruction of Early Pleistocene sites from the Olteţ River Valley of Romania

The Early Pleistocene is recognized as a time of major global climatic and environmental change, including increasing aridity, significant spread of grasslands, and substantial faunal turnovers and dispersals. Importantly, this is the first time hominins are found in Eurasia. Reconstructing the types of environments that existed during this time is imperative for understanding mammalian, including hominin, dispersal patterns relative to climatic change. One proposed dispersal corridor across Europe is the Danube River. Here we characterize the 2.2 to ~1.1 million years ago (Ma) paleoenvironments surrounding one of the tributaries to the Danube, the Olteţ River, in southern Romania using a multiproxy approach, including taxonomic uniformitarianism, dental mesowear, dental microwear, enamel stable isotope (carbon and oxygen), and coprolite/palynology analyses, and compare our results to other penecontemporaneous Eurasian sites. Older sites from this region, Grăunceanu and La Pietriş, both dating to 2.2–1.9 Ma, are reconstructed as being primarily open, though with some nearby woodlands and significant water resources. Fântâna lui Mitilan, which is younger (1.8–1.1 Ma), is reconstructed as slightly more closed, though still relatively open in nature. These results are similar to reconstructions for other Early Pleistocene Eurasian sites, including ones with and without hominins, suggesting that hominins were likely not inhibited from dispersing across Eurasia due to environmental constraints at this time.