From the PPNA to the PPNB : new views from the Southern Levant after excavations at Zahrat adh-Dhra' 2 in Jordan

Results from excavations at the Pre-Pottery Neolithic A (PPNA) site of Zahrat adh-Dhra' 2 (ZAD 2) in Jordan promise to resolve ambiguity over the introduction of the Pre-Pottery Neolithic В (PPNB) period in the southern Levant. Zahrat adh-Dhra ' 2 is the first southern PPNA site to date exclusively to the late PPNA period (9 600-9 300 BP/ 9 200-8 300 cal ВС). The settlement is a small mound containing a single phase of curvilinear architecture. It has yielded a range of characteristic PPNA material culture items and practices, including evidence of cranial removal, a varied ground stone industry with cup-hole mortars, geometrically incised plaques and pebbles ; and a lithic assemblage which includes bladelet cores, a preponderance of bladelets, borers, Beit Та 'amir sickles, Hagdud truncations, picks, edge-ground axes, and tranchet axes. It lacks typical PPNB features such as naviform blade core technology, and notched and tanged projectile points. It also bears evidence for a subsistence economy based on hunting, gathering and the cultivation of cereals and possibly legumes (so-called "pre-domestication cultivation"). ZAD 2 casts doubt upon the authenticity of a prominent chronological scheme which places the southern Levantine Early PPNB phase dating from (9 600-9 200 BP/ also 9 200-8 300 cal ВС). Details of the radiocarbon dates obtained for ZAD 2 and their relationship to the stratigraphie order of the site are given here. Nevertheless, a marked plateau on the early Holocene part of the radiocarbon calibration curve renders it difficult to sequentially order calibrated dates within the 9 600-9 200 BP period, and thus to distinguish between the alternative chronological schemes. In the future, Bayesian modeling of date sequences from individual sequences may assist in this regard. Bayesian modeling of the ZAD 2 dates was undertaken here in order to estimate a likely occupational span for the site. This analysis suggests that the occupation of ZAD 2 can be constrained to the period 8 800-8 450 cal ВС. Yet more recently discovered than ZAD 2, a new phase at the site of'Motza in Israel promises to further elucidate the question of the EPPNB in the southern Levant. With these fresh perspectives newly at hand, we review evidence from several southern Levantine sites previously claimed as exemplars of the southern EPPNB. We also examine their relation to Syrian Pre-Pottery Neolithic sites ; in particular Dja 'de al-Mughara and the new work at Tell Aswad in the Damascus Basin which has radically altered our understanding of that site and weakened its pivotal importance as a reference point for the southern Levantine PPNA and EPPNB. We conclude that, according to the debate as it has been played out in the uncalibrated chronology, the EPPNB phase originated in north Syria around 9 600 BP and the southern Levantine PPNB began around 9 350/9 300 BP.