Eurasian Prehistory, 5 (1): 47- 83. QUANTIFYING DIACHRONIC VARIABILITY: THE 'AIN DIFLA ROCKSHELTER (JORDAN) AND THE EVOLUTION OF LEVANTINE MOUSTERIAN TECHNOLOGY Mentor Mustafa' and Geoffrey A. Clark2 1 Department ofAnthropology, Boston University, 232 Bay State Road, Boston, MA 02215; [email protected] 2 Department ofAnthropology, Arizona State University, Tempe, Arizona; 85287-2402; [email protected] Abstract Typological, technological, and metrical analyses of a lithic assemblage from the 'Ain Difla rockshelter in west­ central Jordan are consistent with the results of previous studies that align 'Ain Difla with the Tabun D-type Levantine Mousterian. Technological and typological affinities are discernible from a direct comparison of tools from this assem­ blage with those found in Tabun layer D, as well as metrical and categorical comparisons between 'Ain Ditla and other well-known Tabun D Mousterian sites. The 'Ain Difla sample is dominated by elongated Levallois points. Blanks were obtained from both uni- and bipolar convergent and predominantly Levallois cores that show evidence of bidirectional flaking. The typological and technological comparisons reported here suggest that the evolution of the blade-rich Mouste­ rian can be viewed as a continuum between the early (Tabun) and late (Boker Tachtit) Mousterian; that (on any index) 'Ain Difla falls somewhere around the middle of this continuum, and that Mousterian laminar technologies develop more or less continually into the early Upper Paleolithic Ahmarian. INTRODUCTION rich technologies of the early Upper Paleolithic The 'big deal about blades' is that their pres­ Ahmarian (e.g., Marks, 1983a, b). Here we assess ence in lithic repertoires has great temporal depth, the empirical support for this contention by exam­ extending far back in time before any construal of ining a sample of lithic artifacts from 'Ain Difla, a the Upper Paleolithic (Bar-Yosef and Kuhn, Jordanian site that appears to fall 'in the middle' 1999; Bar-Yosef, 2001; Bar-Yosef and Meignen, of this progression, both temporally and in terms 200 I ; Meignen and Bar-YOsef, 2002), and that of its lithic industries. If continuity in the evolu­ there is no justification for linking blade produc­ tion of laminar technologies is established tion to any particular hominid, aspect of hominid through 'A in Difla, it would constitute evidence anatomy, or to any major change in the behavioral relevant to the now-global debate on the origin of capacities of hominids. This study utilizes a anatomically modem humans. blade-dominated assemblage to shed light on the The origin of anatomically modem humans dynamics of modem human origins. In the Le­ continues to be the subject of a heated and ongo­ vantine Mousterian, some researchers (e.g., Mo­ ing debate (see, e.g., papers in Mellars and nigal, 2002) argue that the evolution of laminar Stringer, 1989; Mellars, 1990; Brauer and Smith, technologies can be viewed as a continuous pro­ 1992; Nitecki and Nitecki, 1994; Clark and Wil­ gression from early Mousterian (i.e., Tabun layer lermet, 1997; Bar-Yosef and Pilbeam, 2000; D) to late Mousterian (i.e., Boker Tachtit levels 1 Straus and Bar-Yosef, 2001;· Straus 2005) be­ and 2), thus leading up to the unmistakably blade- tween two competing models or conceptual 48 M. Mustafa & G. A. Clark frameworks: 1) the multiregional continuity cording to Bar-Yosef (2002), in Western Europe. model (e.g., Wolpoff, 1989; Wolpoff eta/., 1994, The modem human fossils from the Israeli sites of 2000 and references therein) and 2) the recent Af­ Qafzeh and Skhul are dated to early oxygen iso­ rican origin (RAO) or replacement model (e.g., tope stage (OIS) 5, from 125 to 100 kya, although Stringer, 1989, 1994; Stringer and Gamble, 1993; absolute chronological orderings that agree with Stringer and MacKie, 1996 and references stratigraphy remain elusive ( cf. Jelinek, 1992; therein). Convinced that continuity is visible in Bar-Yosef, 1992). In any event, the available evi­ the archaeological and human fossil data (Clark dence suggests that anatomically modem humans and Lindly, 1989a, 1989b; Frayer et al., 1993; have been around much longer than previously Wolpoff et al., 2001) and supported by studies of thought and, given a date of c. 127 kya for the C1 symbolic and mortuary behavior (Lindly and Neanderthal woman at nearby Tabun (Griin et al. , Clark, 1990; Riel-Salvatore and Clark, 2001), the 1991 ; Griin and Stringer, 2000), they might have multiregional continuity model (MC) holds that coexisted (Bar-Yosef eta/., 1992) and interacted archaic Homo sapiens populations in Africa and (Kaufman, 2001) with archaic human populations Eurasia evolved independently into anatomically for an extended period of time. Faunal analyses modern humans and that gene flow through inter­ indicate that, although these two human popula­ actions between neighboring groups was suffi­ tions could have occupied neighboring territories, cient to maintain species integrity. The differ­ they might have used their environments in differ­ ences between archaic and modern Homo sapiens ent ways, with modem humans practicing a strat­ are thus argued to be subspecific or populational, egy of circulating, seasonal, residential mobility, rather than specific (Hawks and Wolpoff, while archaic humans were more logistically or­ 2001a- b). ganized, hunted more frequently, and were more Emphasizing the results of genetic analyses residentially stable (Lieberman and Shea, 1994; of human mitochondrial DNA (Stringer and An­ Shea, 2003), thus tending to confirm the climati­ drews, 1988; Stoneking and Cann, 1989), Nean­ cally-driven settlement-subsistence models for derthal DNA sequences (Krings et al., 1997), and the central Negev highlands originally proposed 'spread-and-replace' scenarios drawn from cer­ by Marks and Freidel (1977) on the basis of ar­ tain construals of pattern in the archaeological chaeological survey data. record (e.g., Klein, 1992), the recent African ori­ In searching for archaeological evidence that gin model maintains that anatomically modem might help resolve the question of our origins, Je­ humans arose as a speciation event in an isolated linek (1977, 1981, 1982a, 1994) identified a grad­ region of east (and possibly south) Africa, and ual increase in the variance of the width-to-thick­ that they migrated, radiated or dispersed from Af­ ness ratio of complete flakes from Garrod's Layer rica into Eurasia after c. 100 kya, eventually re­ D at Tabun cave on Mt. Carmel, Israel. This sug­ placing all other archaic hominids over the range gested a local "continuity in cultural develop­ originally colonized by Homo erectus. It has also ment" (Jelinek 1982a: 1369). Despite the signifi­ been argued that stratigraphic gaps might reflect a cant stratigraphic hiatus between Tabun D and C 'non-continuous occupation • of the Levantine as documented for example by Farrand (1979), sites (Bar-Yosef, 1991: 580), thus making an em­ Jelinek (esp., 1981 and 1982b) and Mercier eta/. pirical assessment of the credibility of both mod­ (1995), the Mousterian levels in this site do not els suspect (e.g., Bar-Yosef, 1991; cf., Clark, show an obvious intrusive element as reflected by 1992). the trend toward the production of wider and thin­ For a long time, it was assumed that the ori­ ner flakes which was gradual and continuous over gins of anatomically modem humans coincided the represented sequence. Jelinek argued that this with the archaeological transition from the Mid­ pattern of technological stability reflected a dis­ dle to the Upper Paleolithic in the 10 millennia tinctive 'paleocultural' behavioral repertoire that bracketing 40 kya. With the help of new dating contrasts with the fully modem 'cultural' behav­ techniques, however, the emergence of anatomi­ ior evident in the Levantine UpP.er Paleolithic (Je­ cal modernity was uncoupled from the archaeo­ linek, 1982a: 1375). He also suggested that in the logical transition (Bar-Yosef, 1993) except, ac- "absence of conclusive contrary evidence (his The 'Ain Difla rockshelter (Jordan) 49 italics), this trend strongly supports a local devel­ without significant external influence, thus lend­ opment of later more gracile hominids from ear­ ing support to multiregional continuity scenarios. lier more robust forms" (Jelinek, 1994: 85). While If H0 is rejected, and 'Ain Difla is shown to be technological continuity is not necessarily related ' late ' chronologically and 'early' technologically, to directional changes in hominid morphology that would tend to strengthen support for the rela­ (e.g., Bar-Yosef, 1989) and is, in any event, not tively recent (< 100 kya) Levantine colonization definitive proof for multiregional continuity, it models that are the cornerstone of the RAO sce­ nevertheless elevates multiregional continuity as narios. the hypothesis best supported by the available record of lithic technology. Continuity in adapta­ tion as monitored by the archaeology is rendered 'AIN DIFLA more plausible when clear technological trends 'Ain Difla is a Middle Paleolithic site located are present without evidence of intrusive ele­ at c. 780 m above sea level in the Wadi Ali, a ments. The assumption is that, if anatomically southern tributary of the Wadi Hasa in west­ modern African immigrants were moving into the central Jordan. Fluctuations in the course of the Levant and were replacing indigenous archaic Wadi Ali, now located some 17m below the site populations there, they should: 1) carry with them (Fig. 1) , removed much of the fill originally pres­ their own distinctive cultural repertoire; 2) have a ent in the enormous (c. 100m long) rockshelter cultural repertoire that differs from that of the in­ when human use of it ceased around 100 kya. digenes; and 3) be discernible in the Mousterian Still, 'Ain Difla covers an area of c. 35m2 while archaeological record as "assemblages . pro­ its cultural deposits span a little over 7 m at its duced from local raw materials but in techniques deepest sections. The site has emerged as an im­ that prevailed in the original homeland of the portant Middle Paleolithic site partly because of newcomers" (Bar-Yosef, 1994: 25).