Neolithic sites of northern Arabia and palaeohydrology.

<p>Potential Holocene drainage is displayed in blue, with currently severed drainage connections that may have been active during Holocene humid periods interpreted and displayed in grey. Numbered Wadis: (1) Wadi as Sirhan, (2) Wadi al Hamd, (3) Euphrates, (4) Wadi al Batin, (5) Wadi Sabha. Potential palaeolake or swamp deposits detected through remote sensing which may relate to Holocene humidity are displayed for the region surrounding Jubbah. All data is overlain upon SRTMv4 elevation data <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0068061#pone.0068061-Jarvis1" target="_blank">[124]</a> and Natural Earth 2 offshore data. Archaeological site locations calculated from survey data of the ‘Comprehensive Archaeological Survey Programme’, more information is provided in Groucutt and Petraglia <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0068061#pone.0068061-Groucutt1" target="_blank">[111]</a>.</p

Burins from JQ-101.

<p>One long burin spall is shown bottom right.</p

Total number of lithics from the general surface collection and from the six trenches (systematic collection).

<p>Total number of lithics from the general surface collection and from the six trenches (systematic collection).</p

Others types of projectile points from JQ-101.

<p>Examples of different types of tanged with no barbs or barbed and tanged arrowheads.</p

Optically Stimulated Luminescence (OSL) dating.

<p>Radial plot of the equivalent dose (D_e) values obtained from 49 individual grains of quartz from sample JQ200-OSL1. Filled circles denote the 46 values used to calculate the weighted mean D_e for OSL age determination, and open triangles are the three values identified as outliers (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0068061#pone-0068061-t001" target="_blank">Table 1</a>). Each point represents the D_e value for a single grain. It can be read off the radial axis by extending a line from zero on the ‘standardised estimate’ axis through the point of interest, and the ‘relative error’ on this D_e can be read by projecting a vertical line to intersect the horizontal axis. The ‘precision’ is the reciprocal of the relative error, so the most precise D_e estimates lie furthest to the right. The grey band is centred on the weighted mean D_e estimated using the Central Age Model. Individual D_e values that are consistent at 2σ with this weighted mean fall within the grey band. This D_e distribution is overdispersed by 23±4%, which is typical for well-bleached samples of quartz that have not been disturbed since burial. See Galbraith and Roberts <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0068061#pone.0068061-Galbraith2" target="_blank">[71]</a> for further explanation of statistical aspects of D_e estimation and display in OSL dating.</p

Map of the Levantine sites with Helwan points.

<p>It shows the Abu Salem points sub-type, based on maps in Kozlowski and Aurenche <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0068061#pone.0068061-Kozlowski1" target="_blank">[73]</a>. JQ-101 lays more than 500 km from the “core area”.</p

Map of the Neolithic Near East with the different geo-cultural zones of the core area (or Fertile Crescent), in green; after Aurenche and Kozlowski [82].

<p>The JQ-101 site is located in the southern part of the Nefud Desert in Saudi Arabia.</p

Map of artefacts distribution on surface at JQ-101, with trenches localisation.

<p>Map of artefacts distribution on surface at JQ-101, with trenches localisation.</p

Three El-Khiam points from JQ-101.

<p>The enlarged views represent the basal ventrally retouched parts (x3). Top one (broken) is in crystal quartz.</p

Raw material types (counts) from the six trenches (systematic collection).

<p>Raw material types (counts) from the six trenches (systematic collection).</p