Universidade Federal do Rio Grande (FURG), Laboratório de Aves Aquáticas e Tartarugas Marinhas, Instituto de Ciências Biológicas & Programa de Pós-Graduação em Oceanografia Biológica, CP 474, Rio Grande, RS, Brazil.
Institut de Recherche pour le Développement (IRD), UMR248 MARBEC, Centre de Recherche Halieutique Méditerranéenne et Tropicale, Avenue Jean Monnet, BP 171, 34203, Sète Cedex, France.
Sci Rep. 2018 Jan 12;8(1):665. doi: 10.1038/s41598-017-18808-7.
Identifying associations between phenotypes and environmental parameters is crucial for understanding how natural selection acts at the individual level. In this context, genetically isolated populations can be useful models for identifying the forces selecting fitness-related traits. Here, we use a comprehensive dataset on a genetically and ecologically isolated population of the strictly marine bird, the brown booby Sula leucogaster, at the tropical and remote Saint Peter and Saint Paul Archipelago, mid-Atlantic Ocean, in order to detect phenotypic adjustments from interindividual differences in diet, foraging behaviour, and nest quality. For this, we took biometrics of all individuals of the colony breeding in 2014 and 2015 and tested their associations with nest quality, diet parameters, and foraging behaviour. While body size was not related to the foraging parameters, the body size of the females (responsible for nest acquisition and defence) was significantly associated with the nest quality, as larger females occupied high-quality nests. Our findings suggest that the small breeding area, rather than prey availability, is a limiting factor, emphasizing the role of on-land features in shaping phenotypic characteristics and fitness in land-dependent marine vertebrates.
确定表型与环境参数之间的关联对于理解自然选择在个体水平上的作用至关重要。在这种情况下，遗传上隔离的种群可以作为识别与适应度相关特征的选择力的有用模型。在这里，我们利用了一个关于大西洋中部热带偏远的圣彼得和圣保罗群岛上的严格海洋鸟类褐鹈鹕（Sula leucogaster）的遗传和生态隔离种群的综合数据集，以检测因饮食、觅食行为和巢质量的个体间差异而导致的表型调整。为此，我们对 2014 年和 2015 年在该繁殖地繁殖的所有个体进行了生物测量，并测试了它们与巢质量、饮食参数和觅食行为的相关性。虽然体型大小与觅食参数无关，但雌性（负责巢的获取和防御）的体型大小与巢质量显著相关，因为体型较大的雌性占据了高质量的巢。我们的研究结果表明，小的繁殖区域而不是猎物的可利用性是一个限制因素，强调了陆地上的特征在塑造依赖陆地的海洋脊椎动物的表型特征和适应度方面的作用。
