ARTICLE IN PRESS Journal of Human Evolution

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2 ARTICLE IN PRESS Jordan Rift (Fig. 1). The archaeological layers of the ‘Ubeidiya Formation have been systematically excavated since 1960 (Stekelis, 1966a,b; Stekelis et al., 1969; Bar-Yosef and Goren-Inbar, 1993) through the late 1990s (Stekelis,1966a; Stekelis et al.,1969; Bar-Yosef and Goren-Inbar, 1993; Guérin et al., 1996,2003; Shea and Bar-Yosef, 1998), and are known for rich faunal (Haas, 1966,1968; Tchernov, 1986; Belmaker, 2006) and lithic assemblages (Bar-Yosef and Goren- Inbar, 1993; Shea and Bar-Yosef, 1998). The primate assemblage includes dental and postcranial material of Macaca sylvanus (Tchernov and Volokita,1986) as well as a small sample of Homo cf. ergaster/ erectus dental material (Tobias, 1966a,b; Belmaker et al., 2002). Estimated dates for the fossil-bearing strata of the ‘Ubeidiya Formation are between ca. 1.6–1.2 Ma. Paleomagnetic analysis of the ‘Ubeidiya Formation indicate that it overlies the ‘Erq el Ahmar Formation, which is dated at 1.96–1.78 Ma (Ron and Levi, 2001) and has a reversed polarity, suggesting that it predates the Brunhes– Matuyama reversal (Opdyke et al., 1983; Braun et al., 1991; Verosub and Tchernov, 1991). Two short, normal paleomagnetic episodes M. Belmaker / Journal of Human Evolution xxx (2009) 1–11 Figure 1. Location of the site of ‘Ubeidiya in the Southern Levant. have been found in strata II 33 and II 23–24 in the Fi member and have been assigned to the Cobb Mt. (1.215–1.190 Ma) and the Gilsa (1.575–1.567 Ma), respectively (Sagi, 2005). The dating of these short polarity events is corroborated by local faunal turnovers. The ‘Ubeidiya fauna can be assigned to a local mammalian fauna biozone older than that in the sites of Bitzat Ruhama, Evron, and Latamne dated to ca. 1.0–1.2 Ma, suggesting that the ‘Ubeidiya normal polarity events in strata II 23-24 and II 33 should both predate the Jaramillo (0.99–1.07 Ma). (For a detailed stratigraphic correlation, see Supplementary Online Material Figure S1) (Belmaker, 2009). Furthermore, the large mammalian assemblage of ‘Ubeidiya is similar to the Farneta faunal unit (the sites of Selvella and Pietrafitta, Italy) (Belmaker, 2006; Martínez-Navarro et al., 2009), which has been dated to ca. 1.6–1.2 Ma (Caloi and Palombo, 1997, and references therein), and the lithic assemblage is similar to those from East African sites (Stekelis et al., 1969; Bar-Yosef and Goren-Inbar, 1993) such as Olduvai Upper Bed II, dated to ca. 1.53– 1.27 Ma (Gowlett, 1979; Cerling and Hay, 1986). Please cite this article in press as: Belmaker, M., The presence of a large cercopithecine (cf. Theropithecus sp.) in..., J Hum Evol (2009), doi:10.1016/ j.jhevol.2009.08.004
The total accumulation between the two normal episodes is ca. 30 m. The micromorphological analysis of the paleolake ‘Ubeidiya delta system included periods of hiatus, probably in the range of several thousands of years during which pedogenic processes occurred, suggesting that the estimated duration of 400 k.yr. is not inconsistent with the geomorphology of the site (Mallol, 2006). The specimen UB 330 described here was found in stratum III 12 in the Li member. It is stratigraphically below the Fi member that contains the short, normal polarity events, indicating that it most probably predates the Gilsa (ca. 1.575 Ma). Thus, the estimated date for stratum III 12 and specimen UB 330 is ca.1.6–1.58 Ma (Figure S2). Materials and methods ARTICLE IN PRESS Figure 2. UB 330, a right calcaneus. A: Medial view, B: Lateral view, C: Plantar (inferior) view, D: Dorsal (superior) view. The scale bar represents 5 cm. The fossil specimen UB 330 (Fig. 2) was compared to calcanei of adult extant and fossil Cercopithecidae. Calcanei were measured from specimens of extant Cercopithecidae species from the American Museum of Natural History, the Museum of Comparative Zoology, as well as one specimen from the personal collection of Philip Rightmire. Comparative fossil material included an unpublished Macaca sylvanus from ‘Ubeidiya (UB 101), as well as two casts of Theropithecus oswaldi (from Kanjera, Kenya), and a cast of Paracolobus chemeroni (Chemeron Fm., Kenya) generously provided by E. Delson. All extant comparative specimens (n ¼ 146) were adult, based on tooth eruption and fusion of limb elements (Table 1). Measurements were taken with digital calipers on both modern and fossil specimens to an accuracy of two decimal places (Fig. 3). Measurements followed Langdon (1986) and Yirga (2002). Analysis was performed on size-adjusted data. Two methods of size adjustments were used. First, raw variables were transformed to size-adjusted Mosimann shape data (Mosimann, 1970; Falsetti et al., 1993; Jungers et al., 1995). Each of the 14 raw measurements 1 The geometric mean is calculated as the nth root of the product of n measurements. M. Belmaker / Journal of Human Evolution xxx (2009) 1–11 3 was divided by the geometric mean 1 , producing 14 size-adjusted ratio variables (designated by the variable name followed by the subscript ‘‘/GM,’’ e.g., Cal 1/GM). Second, 16 ratios were calculated following Langdon (1986), Strasser (1992), and Yirga (2002). Thus, a total of 30 variables (14 Mosimann shape-adjusted and 16 ratios) were used in this analysis (Tables S1 and S2). Size-adjusted values of UB 330 were compared to modern cercopithecid generic means using the single observation means t-test (Sokal and Rohlf, 1995). Multiple comparisons, such as the one performed here, require adjusting the probability values for the number of simultaneous tests to avoid Type I errors. To increase the power of the test, the sequential Bonferroni method was applied (Rice, 1989). A P value of 0.00033 was set as the test criterion of the single sample t-test. Discriminant Function Analysis (DFA) uses correlation metrics to address weight combinations of variables and emphasizes between group variation while minimizing within group variation. In this study, a two-tier stepwise Linear Discriminant Function was applied to the size-adjusted variables using stepwise insertion of variables (maximizing the smallest F ratio) with UB 330 treated as a separate group (Sokal and Rohlf, 1995). First, a DFA was run at the subfamilial level to test the hypothesis that UB 330 could be identified as a member of Colobinae or Cercopithecinae. Second, a DFA was run at the generic level confined to cercopithecines (Cercopithecus, Macaca, Mandrillus, Papio, and Theropithecus). (Methodological considerations of the DFA are presented in the Supplementary Online Material.) Leave-one-out cross validation was used to assess the overall error rate for the DFA. Furthermore, bias and standard error around the predicted posterior probabilities for UB 330 were estimated using the jackknife procedure. This was performed by running the DFA while randomly removing a single observation at a time and iterated for the total number of specimens (n ¼ 150). Linear regressions of cercopithecid indices of calcaneus pedal power arm (Cal 20) and calcaneal load arm (Cal 21) with body mass, have shown significant correlations at the 0.001 significance level Please cite this article in press as: Belmaker, M., The presence of a large cercopithecine (cf. Theropithecus sp.) in..., J Hum Evol (2009), doi:10.1016/ j.jhevol.2009.08.004
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