本期Nature Communications上发表的一篇研究论文报告说,农业在欧洲出现之后区域人口数量锐减,尽管该地区的人口总的来说呈增长趋势。这项工作表明,人口数量的锐减并不像以前所提出的那样是由于极端气候条件。
农业是在距今约8500年前引入爱琴海地区的,然后不断向欧洲各地扩散,在距今7800年前左右到达法国,在距今大约6000年前到达英国、爱尔兰和北欧。在所有情况下,农业的引入都意味着粮食生产和消费模式的一次巨大变化,这将导致人口数量剧增。Stephen Shennan、Sean Downey和本文其他作者发表了新石器时期欧洲各地人口数量的放射性碳数据,并准确测定了人口密度随时间的变化情况。他们发现,在所研究的从法国南部到苏格兰和丹麦的全部12个欧洲不同地区中,可以观察到剧烈的人口波动。事实上他们注意到,在一些情况下,人口减少量达到农耕之后最高水平的30-60%,相当于所估计的在时间上要晚得多的“黑死病”所造成的人口数量减少规模,尽管“中世纪”时期的人口数量要比新石器时期大很多。
作者发现,那些波动无法与气候因素相联系,不过这一人口数量下降的具体原因仍不清楚(生物谷Bioon.com)。
生物谷推荐的英文摘要
Nature Communications DOI:10.1038/ncomms3486
Regional population collapse followed initial agriculture booms in mid-Holocene Europe
Stephen Shennan,Sean S. Downey,Adrian Timpson,Kevan Edinborough,Sue Colledge,Tim Kerig,Katie Manning & Mark G. Thomas
Following its initial arrival in SE Europe 8,500 years ago agriculture spread throughout the continent, changing food production and consumption patterns and increasing population densities. Here we show that, in contrast to the steady population growth usually assumed, the introduction of agriculture into Europe was followed by a boom-and-bust pattern in the density of regional populations. We demonstrate that summed calibrated radiocarbon date distributions and simulation can be used to test the significance of these demographic booms and busts in the context of uncertainty in the radiocarbon date calibration curve and archaeological sampling. We report these results for Central and Northwest Europe between 8,000 and 4,000?cal. BP and investigate the relationship between these patterns and climate. However, we find no evidence to support a relationship. Our results thus suggest that the demographic patterns may have arisen from endogenous causes, although this remains speculative.