Zhoukoudian Locality 1 (ZKD-1), is located 50km southwest of Beijing, near the town of Zhoukoudian [7]. It lies on the northern slopes of Dragon Bone Hill (“Longgushan”), at 128m above sea level. It is a vertical fissure cave hollowed out of Ordovician limestone and measures about 107x25m. The cave is filled with at least 40m of sediments which have been excavated to a level lying some 80m above sea level [1].

There are 17 depositional layers, consisting mainly of breccia, fine gravelly sand, fine sand, silt, clay, charcoal and ashes, and a small quantity of travertine. The lowermost layers 11-17 are fluvial, layers 6-10 are breakdown breccia from the cave walls and ceiling interbedded with silt and sand, layer 5 is travertine, and the uppermost layers 1-4 are silt and travertine with a minor breakdown that accumulated after the collapse of the ceiling. Stone artefacts and hominin fossils have been recovered from layers 1-10. Most have been found in the lower-level layers 8/9 and in the upper-level layers 3-4. Mammalian fossils are found in Layers 1-13, with some primitive carnivores disappearing above layer 5 [1][8][6][9].

A time range of ~230 to 500 kyr for the hominin-fossil-bearing layers has been widely accepted with a few comments. But Shen et al.[6], extended the dates for Locality to ~0.68 to 0.78 Mya using ²⁶Al/¹⁰Be burial dating, together with previously reported U-series dating [10] and palaeomagnetic stratigraphy [11], as well as sedimentological considerations [12][1]. 

Background 

ZKD-1 was investigated in 1921 by Gunnar Andersson [13] and was first excavated by Otto Zdansky in 1921 and 1923. The first fossils Zdansky found were three isolated hominid teeth, although two were not announced until 1926 [14], and the third was not recognized and published until 1952 [15]. All three specimens are currently housed at the University of Uppsala, Sweden. The type specimen for Homo erectus pekinensis, which was then called Sinanthropus pekinensis [16], was a premolar discovered by Bohlin’s team in Locality 1 [17]. From 1928 to 1937, Locality 1 was excavated annually under the field direction of Zhongjian Yang in the early years, and Wengzhong Pei and Lanpo Jia in the later years. 

Skull I and a number of mandibular and dental remains were discovered in 1928, and Skulls II and III were discovered in 1929 [18][19][20]. Hominid discoveries were made each field season until 1937. Fieldwork in locality 1 was halted from 1937 to 1949 because of the outbreak of the Second Sino-Japanese War and the subsequent Japanese invasion. In 1941, the original hominid fossils recovered from 1927-1937 as well as many vertebrate fossils, stone artefacts, and written records were lost, on their way to the United States for safekeeping [7][21][22]. Because of this, most of the studies and discussions about the early finds were based on casts and on descriptions and drawings made by Weidenreich [23].

Excavations in Locality 1 were re-initiated in 1949 by a team directed by Jia [24], producing new Homo erectus pekinensis fossils, including cranial (portions of Skull V), mandibular (Adult Mandible IX), dental, and post-cranial remains [25][26][27][28][7].

Site Function: Debate on Evidence of Fire Use vs Hyena Den

The use of fire by Homo erectus pekinensis in Locality 1 has been a subject of debate by researchers. Burned items such as charcoal, stones, and bones found in the site, were widely accepted as the oldest reliable source of evidence of hominin use and maintenance of fire [2][3][5]. However, based on taphonomy, geochemistry, and spatial analysis, some researchers doubt the evidence of in situ burning at the site, as well as that the Homo erectus pekinensis had to ability to control it [29][30][31][7]. Boaz et al. [31] suggested that Homo erectus pekinensis did not occupy Locality 1 but that their remains were transported into the cave by Hyenas. Goldberg et al. [9] determine that no irrefutable evidence of in situ burning by hominins could be found. However, recent studies found new evidence that indicates Layer 4 contains clear-cut evidence for in situ use of fire including hearth features [32] and at least 15 fossil bones that were heated above 600°C. The high-intensity burning of bones may indicate strong evidence of hominin-controlled use of fire at Layer 4 [5].