Islands have remarkable levels of endemism and contribute greatly to global biodiversity. Establishing the age of island endemics is important to gain insights into the processes that have shaped the biodiversity patterns of island biota. We investigated the relative age of monocots across islands worldwide, using different measures of phylogenetic endemism tested against null models. We compiled a species occurrence dataset across 4,306 islands, and identified 142 sites with neo-, paleo-, mixed and super-endemism. These sites were distributed across the world, although they tended to be more common at low latitudes. The most frequent types of endemism were mixed and super-endemism, which suggests that present-day island biodiversity has frequently been shaped by processes that took place at different points in times. We also identified the environmental factors that contributed most to different types of endemism; we found that latitude, habitat availability and climate stability had a significant impact on the persistence of ancient taxa and on recent diversification events. The islands identified here are irreplaceable both for the uniqueness and the evolutionary history of their flora, and because they are a source of "option values" and evolutionary potential. Therefore, our findings will help guide biodiversity conservation on a global scale.

中文翻译：

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世界各地岛屿的特有分布和相对年龄。

岛屿具有显着的特有性，对全球生物多样性做出了巨大贡献。确定岛屿特有物种的年龄对于深入了解塑造岛屿生物群生物多样性模式的过程非常重要。我们使用针对无效模型测试的不同系统发育特有性测量方法，调查了全世界岛屿上单子叶植物的相对年龄。我们编制了涵盖 4,306 个岛屿的物种出现数据集，并确定了 142 个具有新特有、古特有、混合和超特有现象的地点。这些地点分布在世界各地，尽管它们在低纬度地区更为常见。最常见的特有类型是混合和超特有现象，这表明当今岛屿的生物多样性经常是由不同时间点发生的过程塑造的。我们还确定了对不同类型特有现象影响最大的环境因素；我们发现，纬度、栖息地可用性和气候稳定性对古代类群的持续存在和最近的多样化事件具有重大影响。这里确定的岛屿因其植物区系的独特性和进化历史而具有不可替代性，而且因为它们是“选择值”和进化潜力的来源。因此，我们的研究结果将有助于指导全球范围内的生物多样性保护。