Warm-adapted species survived the cold stages of the past glacial-interglacial cycles in southern European peninsulas and recolonized major parts of Central and Northern Europe in the wake of postglacial warming. However, many of the genetic lineages which differentiated within these refugia predate even the Pleistocene. One of these refugia is the Italian Peninsula with its surrounding islands. In this meta-analysis, we compiled phylogeographic patterns of multiple species across this region. We transformed existing geographic information on 78 animal and plant species (with a total of 471 genetic lineages) within 17 predefined areas into presence/absence matrices. We elaborated three matrices: (i) only old lineages exclusively distinguished by deep splits, (ii) only young lineages distinguished by shallow (i.e. recent) splits, and (iii) presence/absence of the respective species. To infer biogeographic relationships between the predefined areas, we performed bootstrapped neighbour joining cluster analyses on these three matrices. In addition, we reviewed the geological history of Italy to identify causes of the observed biogeographic patterns. We found Sardinia and Corsica to be biogeographically closely linked with each other, and that they diverge strongly from all other regions. Sicily also diverges strongly from all other regions, while the intra-island differentiation was comparatively low. On the Italian mainland, Calabria exhibited the most pronounced biogeographic differentiation, often with several lineages present, resulting from old vicariance events within the region. Furthermore, southern Apulia and the Po Plain with adjoining areas of northern peninsular Italy displayed considerable distinctiveness. Admixture prevailed in the areas between these three regions. The ancient isolation of Sicily, as well as Sardinia plus Corsica, resulted in endemic lineages with only moderate recent exchange with adjacent mainland regions. Pronounced diversification occurs within the Italian Peninsula. The complex tectonic activities, such as shifting (micro)plates, submergence of major parts of peninsular Italy with the genesis of numerous Pliocene islands, in combination with the climatic cycles during the Pleistocene have most likely generated the current biogeographic pattern of species. Immigrations from the Balkan Peninsula into northern Italy partly accounted for the distinctiveness of this region.

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重新审视意大利的生物地理学：遗传谱系证实了其生物群的主要系统地理学模式和更新世前的起源

适应温暖的物种在南欧半岛过去冰期-间冰期循环的寒冷阶段幸存下来，并在冰后变暖之后重新定居中欧和北欧的主要地区。然而，在这些避难所中分化的许多遗传谱系甚至早于更新世。这些避难所之一是意大利半岛及其周围的岛屿。在这项荟萃分析中，我们汇编了该地区多个物种的系统地理学模式。我们将 17 个预定义区域内 78 个动植物物种（总共 471 个遗传谱系）的现有地理信息转换为存在/不存在矩阵。我们详细阐述了三个矩阵：（i）仅以深度分裂为特征的旧谱系，（ii）仅以浅（即最近）分裂为特征的年轻谱系，(iii) 相应物种的存在/不存在。为了推断预定义区域之间的生物地理关系，我们对这三个矩阵进行了自举邻居连接聚类分析。此外，我们回顾了意大利的地质历史，以确定观察到的生物地理模式的原因。我们发现撒丁岛和科西嘉岛在生物地理上彼此密切相关，并且它们与所有其他地区的差异很大。西西里岛也与所有其他地区有很大差异，而岛内分化相对较低。在意大利大陆，卡拉布里亚表现出最明显的生物地理差异，通常存在多个谱系，这是由于该地区古老的替代事件造成的。此外，普利亚南部和波平原与意大利北部半岛的毗邻地区显示出相当大的独特性。在这三个地区之间的地区，混合现象普遍存在。西西里岛以及撒丁岛和科西嘉岛的古老孤立导致地方性血统，最近与邻近的大陆地区只有适度的交流。意大利半岛出现了明显的多元化。复杂的构造活动，例如移动（微）板块、意大利半岛主要部分的淹没以及众多上新世岛屿的起源，以及更新世期间的气候循环，最有可能产生了当前的物种生物地理模式。从巴尔干半岛到意大利北部的移民在一定程度上解释了该地区的独特性。