Human−geographic effects on variations in the population genetics of Sinotaia quadrata (Gastropoda: Viviparidae) that historically migrated from continental East Asia to Japan

Background: Anthropogenic factors potentially affect observed biogeographical patterns in genetic variations of populations, but the effects of ancient human activities on the original patterns that were created by natural processes are unknown. Sinotaia quadrata, a widely distributed freshwater snail species in East Asia, was used to investigate this issue. It is unclear if S. quadrata in Japan was introduced from China, and how different human uses and varying geographic patterns affect the genetic structure of contemporary populations between the two regions. Thus, we investigated the population history of S. quadrata and detected its genetic structure in Japan and continental East Asia. Results: S. quadrata populations first naturally migrated from continental East Asia to Japan, which is associated with the ancient period in Japanese geohistory (about 70,000 years ago). They were then artificially introduced in association with agriculture expansion by human movements in two rec...研究背景：人为因素可能会影响观测到的种群遗传变异生物地理格局，但古人类活动对自然过程所塑造的原始格局的影响尚不明确。本研究以广泛分布于东亚的淡水螺类中华园田螺（Sinotaia quadrata）为研究对象，对该问题展开探讨。目前尚不清楚日本境内的中华园田螺是否由中国引入，也不明确不同人类利用方式与区域地理格局如何影响两国当代种群的遗传结构。据此，本研究对中华园田螺的种群历史展开探究，并解析其在日本及东亚大陆的遗传结构。 研究结果：中华园田螺种群最初由东亚大陆自然迁徙至日本，这一事件与日本地质历史的远古时期（约7万年前）相关。随后，该螺类在伴随人类迁徙的农业扩张过程中被人为引入，共出现两（原文内容未完整给出）