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The Mammal Age Villafranchian is a biochronological unit based on large mammals spanning the interval from Late Pliocene to most of the Early Pleistocene in Europe. ‘‘Villafranchian’’ is a concept of widespread use within the scientific community of continental stratigraphers in Southern Europe. The termVillafranchianwas proposed by Pareto (1865) as a continental stage referring to fluvial and lacustrine sediments in the surroundings of Villafranca d’Asti (Piedmont) that contained remnants ofmammal fauna.The same author also includedwithin the Villafranchian definition mammalian faunas from Upper and Lower Valdarno basins, in Tuscany. It was generally considered to represent the youngest part of the continental Pliocene. Gignoux (1916)proposed a correlation of this stage with his marine Calabrian, the latter assumed at that time to represent the late Pliocene. In 1948, at the 18th International Geological Congress held in London, it was agreed to place the Calabrian at the base of the Pleistocene and consequently, the Villafranchianwas also considered to represent the earliest stage of the continental Pleistocene. Some authors (Azzaroli,1962, 1970) remarked however that the so-called ‘‘Villafranchian mammal assemblages’’ were not homogeneous, nor strictly contemporary. A first attempt to subdivide ‘‘Villafranchian’’ mammal assemblages is probably detectable in the early 1960s pioneering works of Howell (1959), Bout (1960, 1967), Bourdier (1961) and Azzaroli (1962). In the following years, both Heintz (1968, 1970), Heintz et al. (1974) and Azzaroli (1970), Azzaroli and Vialli (1971) proposed a comparable structured sub-division of the Villafranchian. The chronological sub-division of the Villafranchian was thus extensively discussed during two meetings in 1975 and 1976 (Azzaroli, 1977; Alberdi and Aguirre, 1977). As a result, a number of successive faunal units (Azzaroli, 1977, 1983 originally described six) were recognized subdividing the Villafranchian into Early, Middle and Late Villafranchian. Early Villafranchian corresponds to the Late Pliocene from w3.5 to w2.6 Ma (the former Middle Pliocene), the Middle Villafranchian to the early part of the Early Pleistocene (Matuyama pre-Olduvai subchron), from w2.6 to w2.0 Ma (most of the former Late Pliocene), and the Late Villafranchian covers most of the rest of the Early Pleistocene (Matuyama from Olduvai to Jaramillo subchrons), a time span from w2.0 to w1.0 (that includes the latest part of the former Late Pliocene tomost of the former Early Pleistocene). Within these limits the Villafranchian spans from around 3.5 Ma to about 1.0–1.1 Ma (Fig. 2). During this long time interval, remarkable faunal changes took place. The term Villafranchian has come to lose much of its intrinsic value (Azzaroli, 1977) and its name is maintained for historical reasons and for the sake of stability in nomenclature, but has no real meaning unless it is used with definite qualification: early Villafranchian, middle Villafranchian, and late Villafranchian, or better with the indication of a definite faunal unit (Azzaroli, 1992).