Environmental DNA metabarcoding of cow dung reveals taxonomic and functional diversity of invertebrate assemblages

Insects and other terrestrial invertebrates are declining in species richness and abundance. This includes the invertebrates associated with herbivore dung, which have been negatively affected by grazing abandonment and the progressive loss of large herbivores since the Late Pleistocene. Importantly, traditional monitoring of these invertebrates is time-consuming and requires considerable taxonomic expertise, which is becoming increasingly scarce. In this study, we investigated the potential of environmental DNA (eDNA) metabarcoding of cow dung samples for biomonitoring of dung-associated invertebrates. From eight cow pats we recovered eDNA from 12 orders, 29 families, and at least 54 species of invertebrates (mostly insects), representing several functional groups. Furthermore, species compositions differed between the three sampled habitats of dry grassland, meadow, and forest. These differences were in accordance with the species’ ecology; for instance, several species known to be as...昆虫及其他陆生无脊椎动物的物种丰富度与种群丰度正持续下降。这其中包括与草食动物粪便相关的无脊椎动物，自晚更新世以来，它们便因放牧弃置以及大型草食动物的持续减少而受到负面影响。值得注意的是，针对这类无脊椎动物的传统监测工作耗时耗力，且需要相当专业的分类学知识，而此类专业人才正日益匮乏。本研究中，我们针对利用牛粪样本的环境DNA（environmental DNA, eDNA）宏条形码技术开展粪便相关无脊椎动物生物监测的可行性进行了探究。我们从8份牛粪样本中成功检出了隶属于12个目、29个科、至少54种无脊椎动物（多为昆虫）的eDNA，这些物种涵盖多个功能类群。此外，在所采样的干旱草原、草甸与森林三类生境中，物种组成存在显著差异。这些差异与物种的生态习性相符；例如，若干已知为...