Morelli Federico, Benedetti Yanina, Pape Møller Anders
Faculty of Environmental Sciences Department of Applied Geoinformatics and Spatial Planning Czech University of Life Sciences Prague Czech Republic.
Faculty of Biological Sciences University of Zielona Góra Zielona Góra Poland.
Ecol Evol. 2020 Apr 16;10(11):5097-5105. doi: 10.1002/ece3.6263. eCollection 2020 Jun.
Brood parasitism is a breeding strategy adopted by many species of cuckoos across the world. This breeding strategy influences the evolution of life histories of brood parasite species.In this study, we tested whether the degree on diet specialization is related to the breeding strategy in cuckoo species, by comparing brood parasite and nonparasite species. We measured the gradient of diet specialization of cuckoos, by calculating the Gini coefficient, an index of inequality, on the multiple traits describing the diet of species. The Gini coefficient is a measure of statistical dispersion on a scale between 0 and 1, reflecting a gradient from low to high specialization, respectively. First, we tested the strength of the phylogenetic signal of diet specialization index among cuckoo species worldwide. Then, we ran phylogenetic generalized least square (PGLS) models to compare diet specialization, distribution range, and body mass of parasitic and nonparasitic cuckoo species, considering the phylogenetic signal of data.After adjusting for the phylogenetic signal of the data and considering both, species distribution range and species body mass, brood parasitic cuckoos were characterized by higher diet specialization than nonbrood parasitic species. Brood parasitic species were also characterized by a larger breeding distribution range than nonparasitic species.The findings of this study provide an additional understanding of the cuckoos' ecology, relating diet and breeding strategies, information that could be important in conservation ecology.
巢寄生是世界上许多杜鹃物种所采用的一种繁殖策略。这种繁殖策略影响着巢寄生物种生活史的进化。在本研究中，我们通过比较巢寄生和非寄生物种，测试了食性特化程度是否与杜鹃物种的繁殖策略相关。我们通过计算基尼系数（一种不平等指数）来衡量杜鹃食性特化的梯度，该系数基于描述物种食性的多个特征得出。基尼系数是一种介于0和1之间的统计离散度度量，分别反映了从低到高的特化梯度。首先，我们测试了全球杜鹃物种中食性特化指数的系统发育信号强度。然后，我们运行系统发育广义最小二乘法（PGLS）模型，在考虑数据系统发育信号的情况下，比较寄生和非寄生杜鹃物种的食性特化、分布范围和体重。在调整数据的系统发育信号并同时考虑物种分布范围和物种体重后，巢寄生杜鹃的食性特化程度高于非巢寄生物种。巢寄生物种的繁殖分布范围也比非寄生物种大。本研究的结果为杜鹃的生态学提供了更多的理解，将食性和繁殖策略联系起来，这些信息在保护生态学中可能很重要。
