Pinho Catarina J, Dinis Herculano A, Emerson Brent C, Vasconcelos Raquel
CIBIO-InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Laboratório Associado da Universidade do Porto, Campus Agrário de Vairão, Vairão, Portugal.
Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Porto, Portugal.
R Soc Open Sci. 2024 Oct 2;11(10):240870. doi: 10.1098/rsos.240870. eCollection 2024 Oct.
Competitive dietary and morphological divergence among co-occurring species are fundamental aspects of ecological communities, particularly on islands. Cabo Verde (~570 km west of continental Africa) hosts several endemic reptiles descended from common ancestors, with sympatric species exhibiting wide morphological variation and competing for limited resources. To explore the mechanisms of resource partitioning between coexisting species, DNA metabarcoding was used to compare the diets of large and small skinks, and , in sympatric and allopatric contexts on Fogo Island and in a more competitive context on the small and resource-poor Cima Islet. The morphological variation of all populations was also examined to test the character displacement hypothesis and to compare the effect of different competitive scenarios. Results showed significant differences in diet and linear measurements between species and populations. The two sympatric populations of on Fogo and Cima showed similar changes in head morphology compared to the allopatric population, supporting character displacement. The effect of higher competitive pressure on Cima was evidenced by the increased morphological and dietary variation observed. This study demonstrates how sister species develop dietary adaptations/morphologies to maintain stable coexistence, especially in highly competitive scenarios, providing useful insights for effective conservation strategies.
共存物种之间在饮食和形态上的竞争性差异是生态群落的基本特征，在岛屿上尤为如此。佛得角（位于非洲大陆以西约570公里处）有几种源自共同祖先的特有爬行动物，同域分布的物种表现出广泛的形态差异，并争夺有限的资源。为了探究共存物种之间资源分配的机制，利用DNA代谢条形码技术比较了大型和小型石龙子在佛戈岛同域和异域环境下以及在资源匮乏的小西马岛更具竞争性环境中的饮食情况。还研究了所有种群的形态变化，以检验性状替换假说，并比较不同竞争场景的影响。结果表明，物种和种群之间在饮食和线性测量方面存在显著差异。与异域种群相比，佛戈岛和西马岛的两个同域种群的头部形态变化相似，支持性状替换。在西马岛观察到的形态和饮食差异增加证明了更高竞争压力的影响。这项研究展示了姐妹物种如何发展饮食适应性/形态以维持稳定共存，特别是在竞争激烈的场景中，为有效的保护策略提供了有用的见解。
