Phylogeographical analyses of Patagonian terrestrial gastropods as a tool for understanding regional late Quaterary glacial dynamics

自末次盛冰期（LGM）以来巴塔哥尼亚冰原的演变不仅对古气候研究很有意义，因为这些冰原是目前极地地区以外最大的冰原，而且对南美洲南锥体的人口也很重要。尽管现有数据表明末次盛冰期期间冰盖向西延伸在某种程度上是离岸的，但有一些证据表明它并不像普遍认为的那样均匀。西部边缘可能存在无冰区域，可能深深地嵌入末次冰原冰盖中。一方面，这些地区可能被乘船向南迁徙至火之国的人们所利用，另一方面也代表了某些生物的避难所。这一假设应通过一种新方法进行检验，该方法使用分子标记，包括对智利南部太平洋沿岸现存的窄范围和低流动性陆生腹足动物进行 AFLP 指纹识别。通过这种方法，可以显示某些腹足动物种群在末次盛冰期期间是否持续存在，或者它们是否在冰消退后迁移到现代栖息地。将在生物地理和古环境调查的背景下评估所获得的数据。这里应用的组合方法将得到进一步发展，以获得更高的空间和时间分辨率。

The evolution of the Patagonian ice fields since the Last Glacial Maximum (LGM) is not only of interest in respect of palaeoclimate research, as these are presently the largest outside the polar regions, but also with regard to the peopling of the southern cone of South America. Although existing data indicate that the western extension of the ice sheets during LGM was somehow off shore, there is some evidence that it was not as homogeneous as generally believed. It is possible that ice free areas along the western edge existed, possibly quite deeply indented into the LGM ice sheets. On the one hand, these areas could have been used by people migrating by boats as far south as the Land of Fire, and on the other hand represented refugia for certain organisms. This hypothesis shall be tested by a new approach using molecular markers including AFLP fingerprinting on narrow-range and low mobility terrestrial gastropods being extant along the southern Chilean Pacific coast. With this approach, it can be shown whether certain gastropod populations sustained during the LGM or if they migrated to their modern habitats after the ice had retreated. The data to be obtained will be evaluated in the context of bio-geographical and palaeoenvironmental investigations. The combined approach to be applied here will be further developed in order to receive higher spatial and temporal resolutions.