Fig 1.
SZT site location and representative stone tools analyzed in this study.
(A) Sites discussed in this study, SZT: Shizitan; LWC: Longwangchan; XC: Xiachuan; PLG: Peiligang; (B) Shizitan localities along the Qingshui River; (C) 1–6: SZT29 chipped stone tools (1: microblade [MB5]; 2: flake [SF4]; 3: flake [SF5]; 4: flake [SF8]; 5: flake [SF10]; 6: flake [SF23]); 7: composite sickle from Donghulin for comparison [31: plate 2:6]; (D) SZT 14 and 29 grinding stones (8: 29-GS1; 9: 29-GS3; 10: 29-GS5; 11: 29-GS7; 12: 29-GS8; 13: 29-GS13; 14: 14-GS3; all slabs but 11, a handstone).
Table 1.
Chronology and archaeological contexts of SZT14 and SZT29 tools analyzed in this study.
Fig 2.
Modern microfibers and associated elements as comparative references.
(a) Hemp showing dislocations (indicated by arrows); (b) damaged hemp showing twisted ribbon form; (c) flax, showing dislocations (indicated by arrows); (d) flax showing twisted ribbon form; (e) hemp hair cell; (f) hemp pitted vessel cells; (g) hemp clustered crystals; (h) dyed bast fiber, black; (i) dyed bast fiber, blue; (j) hemp stem cross section; (k) dyed bast fiber, pink; (l) dyed bast fiber, red; (m) dyed bast fiber, green; (n) cotton; (o) synthetic fiber (upper) and wool (lower). (b, g, h, i, k-m show brightfield and polarized views of the same image; plant and wool samples collected from China by Li Liu; [j] adapted from [78: fig 3]).
Fig 3.
Usewear traces on SZT29 tools (a–f) compared with usewear and residue on experimental tools (g–m).
(a-f) SZT29 tools. (a) Microblade (MB5), high polish (indicated by red arrows) and fine striations parallel to the edge (indicated by yellow arrows), compare with (g); (b) flake tool (SF4), high polish, compare with (h); (c) handstone (GS7), high polish with micropitting (indicated by black arrows); (d) flake scraper (SF5), fine striations perpendicular to the edge (indicated by yellow arrows); (e) flake tool (SF8), high polish and fine striations perpendicular and parallel to the edge (indicated by yellow arrows); (f) grinding slab (GS8), isolated polished areas (indicated by red arrows). (g–m) Experimental tools. (g) sandstone knife, cutting and scraping velvetleaf stems, 60 min, high polish and fine striations parallel to the edge (indicated by red and yellow arrows); (h) flint flake, scraping hemp ribbon, 30 min, high polish (indicated by red arrow); (i) scraping hemp ribbon with a chert flake shown in lower right; (j) microfibers attached to the chert flake after use; (k–m) epidermis, microfibers, and crystal found in the residue from the chert after use (hemp ribbons were sourced from Hemp Traders in Los Angeles, California).
Table 2.
Major morphological characteristics of hemp and flax microfibers.
Fig 4.
Fiber quantity comparison between residue and control samples.
Control samples contain considerably fewer fibers than residue samples.
Fig 5.
Comparison of multiple types of microbotanical remains (in quantity) between fiber production tools and other tools analyzed.
Fig 6.
Microfibers uncovered from SZT lithic tools.
(a) Z-twist type in fibrillar orientation; (b) S-twist type in fibrillar orientation; (c) bast fiber showing visible Z-twist fibrillar orientation; (d) bast fiber bundle; (e) bast fiber showing prominent dislocations (indicated by arrows); (f) bast fiber showing less prominent dislocations (indicated by arrows) and cross markings; (g) damaged fiber showing twisted ribbon form, likely hemp; (h) long and entangled fiber; (i) very damaged UNID fibers (d, i, j showing both brightfield and polarized views).
Fig 7.
Bast fiber associated elements from SZT lithic tools.
(a) A large clustered crystal, resembling velvetleaf (14-GS3); (b) a group of small clustered crystals, resembling hemp (29-SF4); (c) small clustered crystals attached to epidermis; (d) enlarged image of a crystal from (c); (e) yeast cells in budding process; (f) curved hair cell, resembling hemp; (g) pitted vessel cells. (Crystals, hair cell, and pitted vessel cells are comparable with corresponding elements from modern examples in Fig 2e–2g; all images from 14-GS3 except b).
Fig 8.
Dyed and pigmented fibers, hematite powder, and ostrich eggshell beads from SZT.
(a–e) Fibers dyed blue, pink, green, black, and red; each fiber image showing in brightfield (left) and polarized (right) views (from SZT29); (f) red hematite pigment attached to a fiber, f-2 is an enlarged view of the left end of f-1; (g) hematite pigment attached to an unknown object; (h) hematite powder on PVS sample (f–h from 29-GS3); (i) ostrich eggshell bead showing red pigment on surface and perforation (SZT29 Layer 7 Top); (j) bead exhibiting wear traces (from SZT24).
Fig 9.
Estimated seasonal activities of fibrous, dyeing, and food plants based on Holocene data and LGM-equivalent reconstructions.
Upper: Overlapping ranges of harvesting and production periods for the three plant categories occurring between June and October. Lower: Comparison of modern (May–November) and estimated LGM-equivalent (early June–late October) active seasons, calculated using a −7 °C temperature offset for Shanxi (shaded areas).