Late Quaternary microevolution of endemic Mediterranean island reptiles in response to environmental and anthropogenic change

海洋岛屿长期以来一直吸引着进化生物学家的注意，因为它们构成了自然实验室，可以在空间有限的陆地环境中详细研究进化过程。爬行动物是著名的岛屿研究模型系统，但对现存的常见岛屿爬行动物的调查数量与化石代表之间存在强烈的不匹配。这是不幸的，因为化石岛爬行动物群落代表了研究随时间进化变化的优秀系统，以及根据不断变化的环境进行生态进化的相互作用。在目前的应用中，重点将放在地中海巴利阿里群岛的岛屿爬行动物，特别是伊比沙岛特有的壁虎，Podarcis pityusensis，利用洞穴遗址Es Pouàs的特殊晚第四纪化石记录和对现代种群的调查来解决与冰川/间冰期过渡，人类到达，以及环境和脊椎动物群落的相关变化。a)通过对化石和现存个体和种群牙列的同位素和形态学研究，我们将测试p.p . pityusensis是否在生物和非生物变化中改变了其在伊比沙岛脊椎动物群落中的相对位置；b)利用微型计算机断层扫描和三维几何形态测量学，我们将通过改变其表型表达范围（例如波动不对称性、大小和整体身体比例）来测试pityusensis是否对由冰期/间冰期气候转变、人为因素和群落组成变化引起的环境扰动作出反应。预期结果将首次揭示几万年来岛屿爬行动物对环境变化和人为改变的表型和生态反应的详细时间信息，这不仅从古生物学的角度来看是有趣的，而且有可能为现存种群的保护工作提供有价值的信息。这项研究的一个非常有益的副作用将是重建伊比沙岛脊椎动物的同位素群落组成。

Oceanic islands have long attracted the attention of evolutionary biologists, as they constitute natural laboratories allowing for the detailed study of evolutionary processes in a spatially confined terrestrial environment. Reptiles are famous model systems for island studies, but there is a strong mismatch between the number of investigations on extant island reptiles, which are common, and that on fossil representatives. This is unfortunate because fossil island reptile communities represent excellent systems for studying evolutionary change through time, as well as eco-evolutionary interactions in light of changing environments. In the present application, focus will be on the island herpetofauna of the Mediterranean Balearic Islands, specifically on the endemic wall lizard of Ibiza, Podarcis pityusensis, using both the exceptional Late Quaternary fossil record at the cave site Es Pouàs and investigations on modern populations to address questions on morphological and ecological evolution through time relative to the glacial/interglacial transition, human arrival, and associated changes in environment and vertebrate communities. a) Using isotopes and morphological studies on the dentition of fossil and extant individuals and populations we will test if P. pityusensis shifted its relative position within the Ibiza vertebrate community in response to biotic and abiotic change; b) using micro-computed tomography and 3D geometric morphometrics we will test if P. pityusensis reacted to environmental perturbation induced by glacial/interglacial climatic transitions, anthropogenic factors, and changes in community composition by shifting its range of phenotypic expressions, e.g. in terms of fluctuating asymmetry, size, and overall body proportions. The expected results will, largely for the first time, reveal detailed temporal information about phenotypic and ecological responses of an island reptile to environmental change and anthropogenic alterations over several tens of thousands of years, which will not only be interesting from a paleontological point of view but also have the potential to provide valuable information for conservation efforts on the extant populations of P. pityusensis. A highly beneficial side effect of the study will be the reconstruction of the isotopic community composition of the Ibiza vertebrates through time.