Tuesday, May 16, 2017

Early Pleistocene occurrence of Acheulian technology in North China

Figure 2. Characteristic in situ artefacts from the Shuigou-Huixinggou site in the Sanmenxia Basin. Artefacts include: (A) handaxe (P. 2768); (B) cleaver (P. 2769); (C) cleaver (P. 2752); (D) pick (P. 2770); (E) unifacial chopper (P. 2758); (F) bifacial chopper (P. 2763); and (G) spheroid (P. 2774). The line drawings of artefacts are after Huang (1964). (Scale bars: 5 cm).

Early Pleistocene occurrence of Acheulian technology in North China
Xingwen Li, Hong Ao, Mark J. Dekkers, Andrew P. Roberts, Peng Zhang, Shan Lin, Weiwen Huang, Yamai Hou, Weihua Zhang, Zhisheng An
Quaternary Science Reviews 156 (2017) pp. 12-22

From the paper:

1. Introduction
Acheulian technology is characterized by bifacially and unifacially shaped tool types, such as handaxes, cleavers, picks and other large cutting tools (LCTs) (Isaac, 1969; Bar-Yosef and Goren-Inbar, 1993; Goren-Inbar et al., 2000; Semaw et al., 2009; Lepre et al., 2011; Beyene et al., 2013 ;  Diez-Martín et al., 2015). Its appearance represents a technological advance over the preceding Oldowan technology, and is associated with innovative hominin cognitive and adaptive abilities (Goren-Inbar, 2011 ;  Stout, 2011). Current thinking is that Acheulian technology originated in East Africa (possibly West Turkana, Kenya) at least 1.76 million years ago (Ma) (Lepre et al., 2011), that it became distributed somewhat widely across Africa (e.g., Vaal River Valley and Gona) at ∼1.6 Ma (Gibbon et al., 2009 ;  Semaw et al., 2009), and then spread to the Levant at ∼1.4 Ma (Bar-Yosef and Goren-Inbar, 1993), South Asia at 1.5–1.1 Ma (Pappu et al., 2011), and Europe at 1.0–0.9 Ma (Scott and Gibert, 2009 ;  Vallverdú et al., 2014) (Fig. 1). The 0.8–0.9 Ma Acheulian stone stools from South and central China (Hou et al., 2000 ;  de Lumley and Li, 2008) (Fig. 1) suggest that Acheulian technology arose in China at least during the terminal Early Pleistocene. However, there are only a few sites with in situ Acheulian artefacts from North China with ages ranging from the late Mid-Pleistocene to the Late Pleistocene ( Wang et al., 2014 ;  Yang et al., 2014) (Fig. 1). Thus, it remains enigmatic as to how early Acheulian technology can be traced back in North China, compared with its Early Pleistocene occurrence in South and central China.

Sanmenxia Basin (also Sanmen area), which lies on the southeastern Loess Plateau, is a rich source of stone artefacts and is an important area for understanding the early human occupation of North China (Jia et al., 1961; Huang, 1964; Jia, 1985 ;  Li, 1990). The first Early Pleistocene Paleolithic site in China, that is the Xihoudu site dated at 1.4–1.27 Ma (Zhu et al., 2003 ;  Kong et al., 2013), was found in northwestern Sanmenxia Basin (Fig. 1) in 1961–1962 (Jia, 1985). In 1963, 128 stone artefacts were found from 6 localities in eastern Sanmenxia Basin (Huang, 1964). Among the 128 artefacts, 94 were from the Shuigou and Huixinggou sites (Huang, 1964). At that time the chronology of the Chinese loess-paleosol sequence was not yet established; a tentative Mid-Pleistocene age was suggested for the lithic assemblage based on lithostratigraphic arguments (Huang, 1964). Furthermore, when these artefacts were discovered, consensus was that Acheulian handaxes and cleavers were lacking in East Asia during the period when they flourished in Africa and western Eurasia (Movius, 1948). Therefore, the handaxe and cleavers from the Shuigou and Huixinggou sites (Fig. 2) were not recognized and reported as Acheulian artefacts; instead, they were considered to represent different kinds of choppers that are indicative of a chopper-chopping tool industry (Huang, 1964; Huang, 1987; Huang, 1993 ;  Lin, 1992).

In the present study, we reassess the previously excavated lithic assemblage from the Shuigou and Huixinggou sites. We establish a numerical age for the lithic assemblage using magneto-cyclostratigraphy. We provide definitive evidence of an Early Pleistocene date for Acheulian stone tools in North China, which offers an important new window into the distribution of Acheulian technology out of Africa during the late Early Pleistocene.

[See the original paper for sections 2, 3, and 4.]

5.2. Implications for the distribution of Acheulian technology outside of Africa
Current consensus in defining a lithic assemblage to represent typical Acheulian technology depends on the following characteristic attributes: the ability to produce large flake blanks and to recurrently shape these blanks into LCTs that are typologically qualified as Acheulian tool types (i.e., handaxes, cleavers, and picks) (Isaac, 1969; Semaw et al., 2009; Stout, 2011; Beyene et al., 2013; Diez-Martín et al., 2015 ;  Dennell, 2016). Accordingly, the technological traits (i.e., production of large flakes) and typological traits (i.e., readily attribution of LCTs as handaxes, cleavers, and picks), which are documented in the lithic assemblage from the Shuigou-Huixinggou site, point unambiguously to Acheulian technology.

Our newly established age of ∼0.9 Ma for these artifacts provides evidence for the emergence of Acheulian technology in North China as early as the late Early Pleistocene. The tools are slightly older than the Bose Acheulian stone tools, which are considered the oldest in South China and are dated at ∼0.8 Ma with 40Ar/39Ar dating of in situ tektites ( Hou et al., 2000). Combined with 0.9–0.8 Ma ages for Acheulian stone stools from Yunxian in central China (de Lumley and Li, 2008) and from Sangiran in Indonesia (Simanjuntak et al., 2010), the Acheulian appears to have extended across a large area in East Asia since the terminal Early Pleistocene. Apparently, the hominins with this advanced technology, most likely Homo erectus, were adapted to diverse habitats that ranged from tropical rainforests in Indonesia to subtropical evergreen broad-leaved forests in South China, and now to temperate grasslands in North China during the late Early Pleistocene. This supports the proposition that the Movius Line ( Movius, 1948) over which no Acheulian artefacts were argued to occur in East Asia is no longer an appropriate concept for the Early Paleolithic of East and Southeast Asia and should be disregarded ( Hou et al., 2000; Wang, 2005; Li et al., 2014 ;  Dennell, 2016). Although the presence of late Early Pleistocene Acheulian technology has been established firmly in East Asia, there is no consensus concerning its origin (Li et al., 2014). Some researchers interpret it to have been introduced into China with population movements from the west ( Hou et al., 2000; Wang, 2005 ;  Huang et al., 2009), while another possibility is that these Early Pleistocene Acheulian artefacts were manufactured by the descendants of hominins that left Africa earlier (Lycett and Norton, 2010).

Widespread distribution of Acheulian technology in East Asia, as documented here, is roughly coeval with their first emergence in Europe (e.g., Estrecho del Quípar and Barranc de la Boella, Spain) at ∼1.0–0.9 Ma (Scott and Gibert, 2009 ;  Vallverdú et al., 2014). By comparison, Acheulian technology appeared in the eastern Mediterranean (e.g., ‘Ubeidiya) and South India (e.g., Attirampakkam) as early as ∼1.4 Ma (Bar-Yosef and Goren-Inbar, 1993) and 1.5–1.1 Ma (Pappu et al., 2011), respectively. Combined with ∼0.8–0.7 Ma Acheulian stone tools from Gesher Benot Ya'aqov (Israel) (Goren-Inbar et al., 2000), a widespread Early Pleistocene distribution of Acheulian technology outside of Africa is suggested, with expansion by ∼0.9 Ma across the southern, western, and eastern portions of Eurasia, including temperate North China (Fig. 1).

5.3. Implications for early human occupation of North China
During the late Early Pleistocene, global climate variability shifted from lower-amplitude ∼40 kyr oscillations to higher-amplitude ∼100 kyr oscillations (Clark et al., 2006). This climate transition lasted from ∼1.2 Ma to ∼0.7 Ma (Clark et al., 2006), but occurred in North China (including the Loess Plateau) at 0.9–0.7 Ma (Heslop et al., 2002 ;  Ao et al., 2012). Pollen data indicate mainly savanna grassland conditions on the Loess Plateau during the late Early Pleistocene (Wang et al., 2002 ;  Wu et al., 2004). The occurrence of Acheulian tools in Sanmenxia Basin against such a global climatic and regional environmental background points to the role of climate in shaping the behavior of early humans, which is consistent with the climatic variability selection hypothesis of hominin evolution (Potts, 1998).

The southern Loess Plateau in the middle reaches of the Yellow River north of the Qinling Mountains, including Sanmenxia Basin, was an important habitat for early humans in North China. Many hominin and Paleolithic sites have been found in this region, such as the hominin sites of Gongwangling (1.63 Ma) (Zhu et al., 2015), Chenjiawo (0.65 Ma) (An and Ho, 1989), Dali (0.27 Ma) (Xiao et al., 2002) and Dingcun (0.21–0.16 Ma) (Chen et al., 1984), as well as the Paleolithic sites from Xihoudu (1.4–1.27 Ma) (Zhu et al., 2003 ;  Kong et al., 2013), Luonan Basin (0.8–0.7, 0.4–0.3, and 0.2–0.1 Ma) (Lu et al., 2011b), Lushi Basin (0.62–0.6 Ma) (Lu et al., 2011a), Beiyao (0.2–0.01 Ma) (Du and Liu, 2014), and the Lantian area (0.6–0.03 Ma) (Wang et al., 2014). Combined with the abundant Paleolithic sites in Nihewan Basin, North China (Ao et al., 2013a), including the oldest sites of Majuangou (1.66 Ma) (Zhu et al., 2004) and Shangshazui (1.7–1.6 Ma) (Ao et al., 2013b), there appears to have been a flourishing population of early humans in North China since the Early Pleistocene.
6.  Conclusions
An integrated stratigraphic analysis, involving lithostratigraphy, magnetic susceptibility stratigraphy and magnetostratigraphy, indicates that the Huixinggou section records the upper Matuyama and Brunhes chrons. The Acheulian-bearing layer occurs in a reversed polarity magnetozone below the Matuyama–Brunhes boundary and is probably equivalent to MIS 23, which yields an estimated age of ∼0.9 Ma. This discovery indicates that the emergence of Acheulian technology in North China can be dated back to the Early Pleistocene. Along with archeological evidence from South China and Southeast Asia, the Acheulian now appears to have been widespread in East Asia since the terminal Early Pleistocene. The East Asian occurrences of Acheulian technology are contemporaneous with the first emergence of Acheulian tools in Europe and support a wide geographic distribution of Acheulian technology outside of Africa during the Early Pleistocene. Our results have important implications for understanding early human occupation on the Chinese Loess Plateau and provide guidance for future archeological investigations in this region.

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