Climate induced human demographic and cultural change in northern Europe during the mid-Holocene

Abstract

The transition from hunter-gatherer-fisher groups to agrarian societies is arguably the most significant change in human prehistory. In the European plain there is evidence for fully developed agrarian societies by 7,500 cal. yr BP, yet a well-established agrarian society does not appear in the north until 6,000 cal. yr BP for unknown reasons. Here we show a sudden increase in summer temperature at 6,000 cal. yr BP in northern Europe using a well-dated, high resolution record of sea surface temperature (SST) from the Baltic Sea. This temperature rise resulted in hypoxic conditions across the entire Baltic sea as revealed by multiple sedimentary records and supported by marine ecosystem modeling. Comparison with summed probability distributions of radiocarbon dates from archaeological sites indicate that this temperature rise coincided with both the introduction of farming, and a dramatic population increase. The evidence supports the hypothesis that the boundary of farming rapidly extended north at 6,000 cal. yr BP because terrestrial conditions in a previously marginal region improved.

The Holocene sedimentary record of cyanobacterial glycolipids in the Baltic Sea: an evaluation of their application as tracers of past nitrogen fixation

“…This is too high, even for summer temperatures when the cHABs occur (Kanoshina et al, 2003). TEX 86 -derived summer temperatures (Kabel et al, 2012;Warden et al, 2017) do not exceed 17.5 • C (Fig. 3d).…”

“…The multi-core (MUC) P435-1-4 (length 51.5 cm) was also collected in the Gotland Basin (56 • 57.94 N,19 • 22.21 E) at 178 m wa-ter depth during cruise P435 onboard the R/V Poseidon in June 2012. The dating of the MUC and the brackish section of the GC was based on an age model, obtained by highresolution 14 C dating of benthic foraminifera (Warden, 2017;Warden et al, 2017), which allowed us to date the MUC (as calibrated kilo-years before present, cal. kyr BP, and the corresponding AD date) and the GC (as cal.…”

“…We examined our data using two such indices, the HDI 26 and the HDI 28 (heterocyst diol index of 26 and 28 carbon atoms, respectively), defined as follows: (2012) and Warden et al (2017). Data points derived from the MUC P435-1-4 core are in gray, and those from the GC 303 600 core are in black.…”

“…Data points derived from the MUC P435-1-4 core are in gray, and those from the GC 303 600 core are in black. The stratigraphy is based on age models published elsewhere (Kabel et al, 2012;Warden et al, 2017), and for the deeper part of the GC 303 600 core, it is based on unpublished data on diatom assemblages. The TEX 86 data of Kabel et al (2012) were measured on a different core (MUC 303 600) obtained from the same site, which was correlated to the MUC P435-1-4 core based on the TOC profiles ( Fig.…”

Neolithic genomes reveal a distinct ancient HLA allele pool and population transformation in Europe

“…The genetic data of the Niedertiefenbach sample, along with information obtained from archaeological and osteological analyses, sheds light on the community that used this gallery grave. In total, the skeletal remains of a minimal number of 177 individuals were recovered from the 7 m 2 site, reflecting a very high occupancy rate for a collective WBC burial 35 . The sex distribution in the sample, which was assessed based on diagnostic skull elements, was similar to those described for other prehistoric populations 40 .…”