We compared support for 3 hypotheses that might explain observed morphological variation among islands of 4 species of Caribbean land birds: ecological release from competition and predation pressure, predation pressure from 1 novel predator species (small Indian mongoose, Herpestes auropunctatus), and climate. We measured wing chord, tarsus length, bill length, and mass of Bananaquits (Coereba flaveola), Black-faced Grassquits (Tiaris bicolor), Lesser Antillean Bullfinches (Loxigilla noctis), and Common Ground Doves (Columbina passerina) in Grenada, 2015–2017, and combined these measures with data from 23 other Caribbean islands collated from academic papers and researchers, for a total sample size of 6,518 individuals. We found the strongest support for the ecological release hypothesis, but each of our hypotheses received some support, suggesting that ecological release from competition, predation pressure from mongoose, and climate may all interact to influence morphological adaptations of birds to local conditions in the Caribbean.

中文翻译：

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加勒比地区鸟类形态特征的生态释放和岛屿变化

我们比较了对 3 种假设的支持，这些假设可以解释 4 种加勒比陆鸟岛屿之间观察到的形态变化：竞争和捕食压力的生态释放、1 种新型捕食者物种（小印度猫鼬、金斑疱疹）的捕食压力和气候。我们在格林纳达测量了 Bananaquits (Coereba flaveola)、Black-faced Grassquits (Tiaris bicolor)、Lesser Antillean Bullfinches (Loxigilla noctis) 和 Common Ground Doves (Columbina passerina) 的翼弦、跗骨长度、喙长和质量，2015– 2017 年，并将这些措施与来自其他 23 个加勒比岛屿的数据相结合，这些数据来自学术论文和研究人员，总样本量为 6,518 人。我们找到了对生态释放假说最有力的支持，但我们的每一个假说都得到了一些支持，