Abstract Considering loss of biodiversity a global threat, cost-effective tools for monitoring spatial distribution of species are relevant for conservation planning. The aims of this study were (a) to compare the global pattern of species richness in Cuculidae with species richness of birds, amphibians and mammals; (b) whether it is spatially congruent with hotspot areas of biodiversity at a global scale; and (c) whether the distribution of night light intensity reflecting human population density is associated with cuckoo species richness. We mapped the global distribution of all cuckoo species, classified as parasitic or non-parasitic species. Species richness was calculated at a fixed spatial scale for: Cuculidae, amphibians, birds and mammals. We applied Generalized Linear Mixed Models in order to explore the associations between species richness of each group of animals, night light intensity and hotspots of biodiversity areas at a global scale. Worldwide patterns of species richness of parasitic and non-parasitic cuckoos reflected species richness of birds, amphibians and mammals. In addition, and importantly, species richness of cuckoos was spatially congruent with hotspot areas of biodiversity across the world. Finally, night light intensity was slightly positively associated with species richness of parasitic cuckoos. Our findings confirmed that cuckoos constitute an important surrogate of high species richness of different animal taxa at a global scale: It is easy to learn how to identify cuckoos, whereas other species of birds, mammals or amphibians can only be identified by specialists. Our findings also suggest that other parasitic cuckoo species can be used as a biodiversity surrogate in a similar way as the common cuckoo in Eurasia.

中文翻译：

---

杜鹃物种丰富度与生物多样性热点之间的全球一致性

摘要 考虑到生物多样性的丧失是一种全球威胁，用于监测物种空间分布的具有成本效益的工具与保护规划相关。本研究的目的是 (a) 比较葫芦科物种丰富度的全球格局与鸟类、两栖动物和哺乳动物的物种丰富度；(b) 在空间上是否与全球范围内的生物多样性热点地区一致；(c) 反映人口密度的夜间光照强度分布是否与杜鹃物种丰富度有关。我们绘制了所有杜鹃物种的全球分布图，分为寄生或非寄生物种。物种丰富度是在固定空间尺度上计算的：Cuculidae、两栖动物、鸟类和哺乳动物。我们应用广义线性混合模型来探索全球范围内每组动物的物种丰富度、夜间光照强度和生物多样性区域热点之间的关联。寄生和非寄生杜鹃的全球物种丰富度模式反映了鸟类、两栖动物和哺乳动物的物种丰富度。此外，重要的是，杜鹃的物种丰富度在空间上与世界各地的生物多样性热点地区一致。最后，夜间光照强度与寄生杜鹃的物种丰富度略呈正相关。我们的研究结果证实，杜鹃是全球范围内不同动物分类群高物种丰富度的重要替代物：很容易学习如何识别杜鹃，而其他鸟类物种，哺乳动物或两栖动物只能由专家识别。我们的研究结果还表明，其他寄生杜鹃物种可以以与欧亚大陆常见杜鹃类似的方式用作生物多样性替代物。