Zhoukoudian or Choukoutien (Chinese: 周口店; pinyin: Zhōukǒudiàn, IPA: [tʂóʊkʰòʊtjɛ̂n]) is a cave system in Beijing, China. It has yielded many archaeological discoveries, including one of the first specimens of Homo erectus, dubbed Peking Man, and a fine assemblage of bones of the gigantic hyena Pachycrocuta brevirostris. Peking Man lived in this cave approximately 750,000 to 200,000 years ago.
The Peking Man Site was discovered by Johan Gunnar Andersson in 1921 and was first excavated by Otto Zdansky in 1921 and 1923 unearthing two human teeth. These were later identified by Davidson Black as belonging to a previously unknown species and extensive excavations followed.
Fissures in the limestone containing middle Pleistocene deposits have yielded the remains of about 45 individuals as well as animal remains and stone flake and chopping tools. The oldest are some 750,000 years old.
During the Upper Palaeolithic, the site was re-occupied and remains of Homo sapiens and its stone and bone tools have also been recovered from the Upper Cave.
The crater Choukoutien on asteroid 243 Ida was named after the location.
Excavation history
Discovery
Swedish geologist Johan Gunnar Andersson first started his explorations of the region in 1918 at an area called Chicken-bone Hill by locals who have misidentified the rodent fossils that are in abundance there, but it was not until 1921 that he and American palaeontologist Walter W. Granger were led to the site known as Dragon Bone Hill by local quarry men. Noticing some white quartz that was foreign to the area he immediately realised that this would be a good place to search for the remains of primitive man.
Excavations were undertaken by Andersson's assistant Austrian palaeontologist Otto Zdansky in 1921 and 1923 unearthing a great deal of material that was sent back to Uppsala University in Sweden for further analysis. In 1926 Anderson announced the discovery of two human molars amongst this material and the following year Zdansky published his finding cautiously identifying the teeth as ?Homo sp.
“ Here is primitive man, now all we have to do is find him! ”
- J.G. Andersson upon discovery of the Peking Man Site
Zhoukoudian Project
Canadian paleoanthropologist Davidson Black, who was working for the Peking Union Medical College at the time, was excited by Andersson and Zdansky's find and applied to the Rockefeller Foundation for funding to undertake a systematic excavation of the site.
Funding was granted and the Zhoukoudian Project commenced excavations in 1927 under the supervision of Chinese geologist Li Jie. That fall a tooth was unearthed by Swedish paleontologist Anders Birger Bohlin for which Black proposed belonged a new species named Sinanthropus pekinensis. The following year Black's excavations uncover more fossils of his new species including teeth, a substantial part of a juvenile's jaw and an adult jaw complete with three teeth. These finds allowed Black to secure an extra $80,000 grant from the Foundation which he used to establish a research laboratory.
Cenozoic Research Laboratory
The Cenozoic Research Laboratory of the Geological Survey of China was established at the Peking Union Medical College in 1928 with the assistance of Chinese geologists Ding Wenjing and Weng Wenhao for the research and appraisal of the fossils unearthed. Black stayed on at the Laboratory as honorary director while excavations continued at the site under Chinese archaeologists Yang Zhongjian, Pei Wenzhong and Jia Lanpo.
Conditions at the site remain primitive with scientists having to ride out to the excavation on mules, staying at caravansaries along the way, and when the first skullcap is unearthed at the site in 1929 it is done by Pei, working in a 40-meter crevasse in frigid weather with a hammer in one hand and a candle in the other. A second skullcap is discovered close to the first in 1930 and by 1932 nearly 100 workers are deployed on the site each day.
Despite the conditions at the site eminent researchers continue to visit. French palaeontologist Pierre Teilhard de Chardin has been a regular visitor to the site since 1926. French archaeologist Henri Breuil visits in 1931 and confirms the presence of stone tools. That same year evidence of the use of fire at the cave becomes accepted.
The workaholic Black passes away one night in 1934 at his office with one of the skullcaps unearthed at the site on his desk. German Jewish anthropologist Franz Weidenreich replaces him as honorary director of the Laboratory and excavations continue uncovering a further three skullcaps in 1936.
Altogether excavations uncoverg 200 human fossils from more than 40 individuals including 5 nearly complete skullcaps before they are brought to a halt in 1937 by the Japanese invasion of China. Reports of Japanese atrocities include the torture and murder of workers at the site, three bayoneted to death and a fourth forced to pull a rickshaw until dying of starvation.
In 1941 the bulk of the finds were lost, never to be recovered, while being transported to safety. Fortunately Weidenreich had taken copies of the fossils to preserve their physical characters.
Post War Excavations
Excavation work was recommenced in 1949 unearthing new Peking Man fossils including 5 teeth and fragments of thigh and shin bone. The following year a third premolar was discovered in the material sent back to Uppsala by Zdansky in 1921 and 1923.
Peking Man Site is designated type section of cave deposits of Middle Pleistocene in North China by the Annual Congress of the National Committee of Stratigraphy of China 1959 and a mandible fragment is unearthed.
Excavations led by Pei in 1966 unearthed a premolar and two pieces of skull fragment, these were discovered to match fragments retained from previous excavations in 1934 and 1936, and the only extant example of a nearly complete skullcap was pieced together.
Excavations at Locality 4 in Zhoukoudian, from 1972–73, unearth a Homo sapiens premolar.
Modern scientific dating techniques confirm that the site was occupied between 770,000 and 230,000 years ago.
Excavation sites
Peking Man Site
Locality 1, also known as Peking Man Site, was the first to be discovered in 1921 under the direction of local quarry men. The site was originally a natural limestone cave although the roof had long since collapsed spreading a layer of breccia and rubble across the top of the deposits. Early excavations in 1921 and 1923 revealed evidence of human habitation from 750,000 to 200,000 years ago. The cave was excavated from 1927-37 yielding 200 human fossils (from 40 individuals) identified as Homo erectus, more than 10,000 pieces of stoneware, several cinder layers indicating fire use in early man, as well as animal fossils from 200 separate species. Tragically the bulk of this material was lost in 1941 during the Japanese Occupation and has never been recovered. Excavations recommenced in 1949 and continued to yield fossils and artefacts making this site one of the most fruitful sources of material from the Middle Pleistocene era.
A total of 13 layers have been excavated at the site to a depth of nearly 40 m.
Layers below this have been shown by test-pit drilling to not contain fossils or stoneware and have never been excavated.
East Slope
Part of Peking Man Site this slope was excavated 1930–58 and again in 1978–79 by a multi-disciplinary research mission. Excavation have dug to a depth of 7m through Layers 3-6 and have unearthed stone tools, burned bones and ashes, and fossils of bird, reptile and mammal species.
Pigeon Hall
Pigeon Hall was named in honour of its frequent visitors and was connected with Peking Man Site by workmen in 1928. Excavations from 1930-31 unearthed numerous Peking Man bones (including mandible, clavicle and parietal bone), signs of fire use (including a scorched redbud stick), and stone tools of quartz and green sandstone.
Upper Cave
Situated on the upper part of Dragon Bone Hill this cave was discovered in 1930 and excavated from 1933–34 during which time the roof and north facing opening were removed. Excavations found evidence of human habitation in the cave dating back to 10,000 to 20,000 years ago. The cave was divided into an upper level living quarters and a lower level burial ground, while a small recess on the lower level acted as a natural animal trap. Finds unearthed included three human skulls and other remains from at least eight individuals identified as Archaic Homo sapiens, tools and ornaments made from stone and bone, and numerous animal bones including complete skeletons of large mammals caught in the lower level trap. Also white powder sprinkled around the remains on the lower level indicates the inhabitants practiced burial rites.
Other Localities
More than 20 fossil bearing localities have been excavated in Zhoukoudian to date.
Locality 2
This north-south running fissure is filled with red binder soil and dates to the Middle Pleistocene era. Excavations in 1921 concurrent with those at Peking Man Site unearthed mammalian fossils including hamster, rhino and Chinese hyena.
Locality 3
Discovered in 1927 this east-west running fissure is filled with breccia and dates to the late Middle Pleistocene era. Excavations in 1933 unearthed mammalian fossils including porcupine, racoon dog and badger.
Locality 4
Discovered in 1927 this north-south running fissure is filled with yellow sandy clay and dates to the late Middle Pleistocene era. Excavations from 1937–38 unearthed stoneware, burned bones and seeds (indicating fire use in early man) and fossils of jackal and deer. A second excavation in 1973 unearthed a human premolar and the fossilised remains of 40 mammalian species including macaque, pig, bear and horse.
Cap Deposit
This deposit, located 60m above the riverbed, is filled with layers of sand and gravel and dates to the late Early Pliocene era. Excavations from 1937-38 unearthed mammalian fossils including civet and bamboo rat.
New Cave
Discovered in 1967, this cave connects with Locality 4 to its south. The deposits formed by hydrostatic sedimentation in stagnant water conditions contained no fossils or human related artefacts.
Locality 12
Discovered in 1933, when Locality 3 was being excavated, this column shaped corrosion pit is filled with red grit and dates to the late Early Pleistocene era. Excavations unearthed fossils of 22 mammalian species including sabre-toothed tiger and an extinct primate.
Locality 13
This fissure in a limestone mound 1 km south of Peking Man Site dates to the early Middle Pleistocene era and is the earliest site of cultural remains excavated so far at Zhoukoudian. Excavations of the thin-bedded sandy clay about 50m above the river bed have unearthed stone artefacts, ash and charred bones and 36 species of deeply fossilised mammalian fossils including thick-jawed giant deer and sabre-toothed tiger.
Locality 14
This narrow limestone cave 1.5 km south of Peking Man Site dates to the Early Pliocene era and has yielded some of Zhoukoudian oldest fossils, dating back 5 million years. Excavations, in 1933, 1951 and 1953, of the thin-bedded fine sandstone about 70m above the river bed have unearthed more than 600 nearly complete fish fossils of four different species, two of which are now extinct.
Locality 15
Discovered in 1932 this relatively young site dates to around 100,000 to 200,000 years ago. Excavations from 1934–35 revealed three layers; an upper layer of loess and limestone debris; a middle layer containing ash, stoneware, burned bones and hackberry seeds; and a lower layer of red clay containing stoneware and bird and mammalian fossils including woolly rhino, giant deer and gazelle. The site has yet to be fully excavated.