Table 1.
The approximate chronology of different cultural groups across northern China.
Fig 1.
A map showing all sites analysed in this study and the major geological features of northern and northwestern China.
A key to site IDs is provided in the Table 2. The map was created using QGIS Version 2.12.0 for OSX (www.qgis.org). All maps used are in the public domain (CC0), sourced from Natural Earth (www.naturalearthdata.com).
Table 2.
Names, references (in brackets), cultural phases, coordinates (latitudes and longitudes), and elevations of all sites included in the database.
For the time period of each cultural phase please refer to Table 1. Site ID corresponds to number shown on Fig 1. NCP refers to North China Plain, QJ refers to the Qinjin region, GQ refers to the Ganqing region. For more detailed description of each region please refer to section 3.
Table 3.
Means and standard deviations of δ13C (‰, VPDB) and δ15N values (‰, AIR) of values from individuals from each phase.
Sites with * also have dental pathology data.
Table 4.
Summary of dental caries prevalence in samples (teeth affected / total of teeth preserved for examination).
Fig 2.
Bone collagen δ13C values of humans from all sites discussed in this study, organized by province groups.
Note that due to the 1000-year gap between the last two groups of data from the GQ region, the smooth line was not extended to the last group.
Fig 3.
Boxplots showing changes in the prevalence of dental caries before and after 4000 BP in the three regions: a) changes in prevalence of dental caries in NCP; b) changes in prevalence of dental caries in QJ; c) changes in prevalence of dental caries in GQ.
Table 5.
Summary statistics of the dental caries data (%).