Homo antecessor

The earliest non-ergaster/georgicus/erectus hominins in Europe are the specimens from Gran Dolina Cave, Level TD-6, in the Atapuerca Hills of northern Spain, allocated to their own species, Homo antecessor (Bermúdez de Castro et al., 1997) and dating to around 780,000 years ago (Parés & Pérez-González, 1995; Falgueres, 1999) (Figure 7.1). Bermúdez de Castro et al. (1997) argue that the new species evolved from H. ergaster and represents the likely stem species that gave rise to the Neanderthal lineage and to modern humans. Given the fragmentary nature of the specimens from Gran Dolina, however, their specific distinction from the later European and African H. heidelbergensis remains debatable. The supposedly distinctive features of this H. antecessor, including increased cranial capacity, reduced facial prognathism, well-developed canine fossa, and angled inferior cheekbone, are also characteristic of

Figure 7.1 ► Homo antecessor cranial fragment (ATD6-15) from Atapuerca: Gran Dolina.

H. heidelbergensis (F.H. Smith, 2002). Primitive features that H. antecessor shares with H. ergaster and H. erectus include the presence of male lower canine and premolar cingula, and asymmetry in the crowns of the lower third premolars (B.A. Wood & Richmond, 2000).

Postcranially, H. antecessor was relatively gracile, most similar to H. ergaster and modern H. sapiens, contrasting with most of its successors, including H. heidelbergensis and H. neanderthalensis. As such, it was evidently not adapted to cold conditions, but like H. ergaster and H. georgi-cus, it was adapted to a relatively warm, temperate climate (see partly B.A. Wood & Richmond, 2000).

The allocation of these specimens to either H. antecessor or H. heidel-bergensis is not merely an academic exercise; it has major implications for the way we interpret later human evolution. For example, if the Gran Dolina hominins represent H. heidelbergensis, then this species may have origins in Europe as opposed to Africa, or it might represent a hypothetical earlier African deme of H. heidelbergensis that had migrated into Europe. Most people currently recognize as the earliest representative of H. heidelbergensis the large-brained Bodo skull from Ethiopia, which has a cranial capacity of around 1300 cc (Rightmire, 1996) and is currently dated to 600,000 years ago (Clark et al., 1994), which is almost 200,000 years later than the hominins from Gran Dolina. If the Gran Dolina material does, however, represent a new species, did H. heidelbergensis evolve from this European population, thus implying a migration back into Africa?

The material culture associated with these early European hominins has been assigned to the Mode 1 technology observed in Africa (Carbonell et al., 1995), though this type of technology has also been associated with H. erectus in Asia (Foley & Lahr, 1997) and H. ergaster (H. georgicus?) in Georgia (Gabunia et al., 2000a). This system of lithic classification was originally defined by Clark (1977) and is based on a pebble tool industry (Oldowan) commonly associated with simple flakes struck off pebbles, resulting in choppers and flakes (also see Foley & Lahr, 1997). Thus, these hominins are not associated with the derived Mode 2 technology that characterizes the later African demes of H. ergaster, not to mention H. heidelbergensis.

While it is currently not possible to ascertain the phylogenetic significance of H. antecessor, we can see that the pattern of human evolution from their first appearance in Europe is not as straightforward as previously thought, especially if we consider the implied H. erectus migration into Europe, as suggested by the Italian Ceprano H. erectus specimen (see previous chapter) at around the same time as the Gran Dolina hominins in Spain make their appearance, not to mention the earlier migration into far southeastern Europe of H. ergaster. While these species are anatomically distinctive, they all maintained an earlier inherited Mode 1 technology from their likely African ancestor(s).

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