Electron spin resonance (ESR) and thermal ionization mass spectrometric (TIMS) ²³⁰Th/²³⁴U dating of teeth in Middle Paleolithic layers at Amud Cave, Israel

Abstract

Electron spin resonance (ESR) dating and thermal ionization mass spectrometric 230 Th/ 234 U dating was conducted on six teeth from the prehistoric site of Amud Cave. By combining the ESR and 230 Th/ 234 U analyses, we obtained burial ages for teeth in various layers of the site. Layer B 1 /6-7, from which the Amud I Neanderthal skeleton was recovered, is dated to 53 Ϯ 8 ka. Layer B 2 /8, which yielded other important human remains including the Amud 7 skeleton, gives a mean burial age of 61 Ϯ 9 ka. One tooth from the lowest layer (B 4 ) yielded a date of 70 Ϯ 11 ka, but another tooth from this layer gave an 113 Ϯ 18 ka. Despite this discrepancy, these ages agree with previously published TL ages on heated flints for the corresponding layers. This agreement between ESR on tooth enamel and TL on burned flint is also seen at all other sites studied with both methods in Israel. ᭧

A critique of the chronometric evidence for hominid fossils: I. Africa and the Near East 500–50ka

“…Table 5 shows the results of the Bayesian stratigraphic models for Amud. In comparison to the summary of Valladas et al (1999), the new chronology is less certain, but in comparison to the averages presented by Rink et al (2001), the 95% probability intervals are more precise than their 1σ ranges. The age for layer B 1 , which contained the Amud I Neandertal, suggests that it is similar in age to the Kebara Neandertal or slightly younger.…”

“…. The ESR dates on teeth (Rink et al, 2001) and TL dates on burnt flints have been obtained from the three relevant layers. The latter papers contain inconsistencies in the chronometric data.…”

“…Flints from Squares O14 and O15 were excluded due to disturbances that are likely to have altered the external radiation dose. Examination of the values in the tables of Rink et al (2001) and reproduction of their calculations show that all samples were dated using in situ measurements by gamma-spectrometry or TL dosimetry and none of the gamma dose rates used were calculated from sediment compositions, despite what is stated in the text. The in situ measurements were also used here.…”

“…Following Rink et al (2001), they were assumed to represent radiation dose with a water content of 10% and an uncertainty of 10%. Using the US-ESR uptake model, Rink et al (2001) computed ages that fall midway between the EU and LU ages, which themselves only differ by a few thousand years. Table 5 shows the results of the Bayesian stratigraphic models for Amud.…”

The Upper Palaeolithic of Europe

“…However, whether the Ehmiran itself was made by modern humans remains a moot point; given the lack of associated fossils, it could just as well have been made by Neanderthals, and all the more so given the terminus post quem for the latter's disappearance from the Near East provided by the TL date (about ifty-three thousand years ago) obtained for level B1 of Amud (Israel), which contained the burial of a Neanderthal adult (Valladas et al 1999;Rink et al 2001;see Chapter 3.1). Both cultures have roots in the preceding MP (as seen, for the core area of the Bohunician, in the technological transition to the UP documented across the different levels of the Piekary IIa site, in southern Poland; Sitlivy et al 2008), and their resemblance probably relects, therefore, convergent, independent invention.…”