Counts of crop seeds, weed seeds, kernels and nut shells in the studied samples.

<p>Counts of crop seeds, weed seeds, kernels and nut shells in the studied samples.</p

Stereoscan photographs of nut shells (suspected).

<p>These suspected fruit shells have radians and ornamentation on the surface. The shell remains were too fragile to be identified accurately; however, we could identify three relatively intact specimens: a. <i>Corylus</i>, Huoshiliang; b. <i>Pinus</i>, Huoshiliang; c. <i>Castanea</i>, Zhaimao.</p

Study sites and their ¹⁴C ages.

<p>Study sites and their ¹⁴C ages.</p

Box plots illustrating changes in the length and width of the seeds of foxtail millet (top) and common millet (bottom) from Neolithic and Bronze Age sites in the agro-pastoral zone of China.

<p>Box plots illustrating changes in the length and width of the seeds of foxtail millet (top) and common millet (bottom) from Neolithic and Bronze Age sites in the agro-pastoral zone of China.</p

Morphological characteristics (average length and width) of carbonized seeds of foxtail millet (<i>Setaria italica</i>) and common millet (<i>Panicum miliaceum</i>).

<p>Morphological characteristics (average length and width) of carbonized seeds of foxtail millet (<i>Setaria italica</i>) and common millet (<i>Panicum miliaceum</i>).</p

Results of AMS radiocarbon dating of samples from cultural horizons at the studied archaeological sites.

<p>All results are reported with 2 sigma error. ¹⁴C ages are calibrated to calendar years using Calib Rev 5.1 and OxCal v4.3.6, with the r:5 IntCal 13 atmospheric curve.</p