The Dmanisi site is located about 85 km southwest of Tbilisi, the capital city of the Republic of Georgia, on the northern slopes of the Lesser Caucasus (Fig. 1), near the village of Patara Dmanisi, at an altitude of 915 m asl. The site sits on a promontory of the Mashavera basalt, 80 m above the present-day water levels at the confluence of the Mashavera and Pinezaouri Rivers. The Early Pleistocene site of Dmanisi was discovered in 1983, under the ruins of the medieval town of Dmanisi. Excavations have yielded hominin fossils, a rich vertebrate fauna, and Mode I (Oldowan) stone artifacts. Occupation of the site began shortly after 1.85 Ma and is documented until about 1.77 Ma (Gabunia et al., 2000a; Vekua et al., 2002; Lordkipanidze et al., 2005, 2006, 2007; Ferring et al., 2011). The temporal and geographic setting and the preservation of at least five hominin individuals make Dmanisi a site that is crucial in understanding patterns of variation, biogeography, and evolution within early Homo (Lordkipanidze et al., 2013). Dmanisi deposits are divided into two major stratigraphic units: Stratum A and B. In the main excavation area ‘Block 2’, volcanoclastic fossiliferous alluvium, which overlies basalt, is approximately 2.5 m thick (Fig. 2). Dmanisi deposits have been considered as Early Pleistocene, about 1.8 Ma in age according to 40Ar/39Ar dating on Mashavera basalt (de Lumley et al., 2002), which underlies the fossil-bearing sediments. Stratum A consists of a series of at least four separate ash falls that conformably overlie the basalt. Stratum B deposits include horizontally extensive ash falls, as well as a complex of deposits that filled pipes and the gullies that formed along collapsed pipes (Ferring et al., 2011). Stratigraphic studies revealed that all the hominin remains come from the base of Stratum B1, dated to ca. 1.77 Ma, based on 40Ar/39Ar dates, paleomagnetic and biostratigraphic constraints (Lordkipanidze et al., 2007), as it is also the case of the small mammal material subject of this study.

Rodents and lagomorphs were the subjects of a previous contribution by Mouskhelishvili (1995), who recognized the following species: Cricetus sp., Kowalskia sp., Meriones aff. tristrami, Mimomys ex. gr. reidi, Apodemus sp., and Ochotona ex. gr. minor. The porcupine Hystrix refossa from Dmanisi was described by Vekua et al. (2010). Although a more updated faunal list was provided by Lordkipanidze et al. (2007), a detailed revision of the existing material from a systematic, paleobiogeographic, and paleoecological point of view has never been carried out. In this article, we tackle for the first time these issues, in relation to one of the first recognized Homo dispersal out of Africa.