Ecological specialization and niche overlap of subterranean rodents inferred from DNA metabarcoding diet analysis

Knowledge of how animal species use food resources available in the environment increases our understanding of ecological processes. However, obtaining this information using traditional methods is a hard task for species feeding on a large variety of food items in highly diverse environments. We amplified the DNA of plants for 306 scat and 40 soil samples, and applied an eDNA metabarcoding approach to investigate food preferences, degree of diet specialization and diet overlap of seven herbivore rodent species of the Ctenomys genus distributed in southern and midwestern Brazil. The metabarcoding approach revealed that species consume more than 60% of the plant families recovered in soil samples, indicating generalist feeding habits of ctenomyids. The Poaceae family was the most common food resource retrieved in scats of all species as well in soil samples. Niche overlap analysis indicated high overlap in the plant families and Molecular Operational Taxonomic Units consumed, mainly amon...

了解动物物种如何利用环境中可获取的食物资源，可增进我们对生态过程的理解。然而，对于在高度多样的生境中取食多种食物类群的物种而言，通过传统方法获取此类信息是一项艰巨的任务。我们对306份粪便样本与40份土壤样本中的植物DNA进行了扩增，并采用环境DNA元条形码（environmental DNA metabarcoding）技术，对分布于巴西南部和中西部地区的7种栉鼠属（Ctenomys）植食性啮齿类物种的食物偏好、食性特化程度以及食性重叠度展开了研究。元条形码分析结果显示，这些物种取食了土壤样本中检测到的60%以上的植物科类群，表明栉鼠类动物具有广食性取食习性。禾本科（Poaceae）是所有物种粪便样本以及土壤样本中检出的最常见食物资源。生态位重叠分析结果显示，被取食的植物科以及分子操作分类单元（Molecular Operational Taxonomic Units, MOTU）存在高度重叠，主要在……