In social species, group members commonly show substantial similarity in gut microbiome composition. Such similarities have been hypothesized to arise either by shared environmental effects or by host relatedness. However, disentangling these factors is difficult, because group members are often related, and social groups typically share similar environmental conditions. In this study, we conducted a cross-foster experiment under controlled laboratory conditions in group-living Damaraland mole-rats (Fukomys damarensis) and used 16S amplicon sequencing to disentangle the effects of the environment and relatedness on gut microbiome similarity and diversity. Our results show that a shared environment is the main factor explaining gut microbiome similarity, overshadowing any effect of host relatedness. Together with studies in wild animal populations, our results suggest that among conspecifics environmental factors are more powerful drivers of gut microbiome composition similarity than host genetics.

中文翻译：

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环境影响而不是相关性决定了社会性哺乳动物肠道微生物组的相似性。

在社会物种中，群体成员通常在肠道微生物组组成方面表现出显着的相似性。人们假设这种相似性是由共同的环境影响或宿主相关性引起的。然而，理清这些因素是很困难的，因为群体成员往往是相关的，而且社会群体通常具有相似的环境条件。在这项研究中，我们在受控实验室条件下对群居的达马拉鼹鼠 (Fukomys damarensis) 进行了交叉寄养实验，并使用 16S 扩增子测序来阐明环境和相关性对肠道微生物组相似性和多样性的影响。我们的结果表明，共享环境是解释肠道微生物组相似性的主要因素，掩盖了宿主相关性的任何影响。结合野生动物种群的研究，我们的结果表明，在同种动物中，环境因素是比宿主遗传学更强大的肠道微生物组组成相似性驱动因素。