Communities are shaped by scale dependent processes. To study the diversity and variation of microbial communities across scales, the invasive and widespread seaweed Agarophyton vermiculophyllum presents a unique opportunity. We characterized pro‐ and eukaryotic communities associated with this holobiont across its known distribution range, which stretches over the northern hemisphere. Our data reveal that community composition and diversity in the holobiont vary at local but also larger geographic scales. While processes acting at the local scale (i.e., within population) are the main structuring drivers of associated microbial communities, changes in community composition also depend on processes acting at larger geographic scales. Interestingly, the largest analysed scale (i.e., native and non‐native ranges) explained variation in the prevalence of predicted functional groups, which could suggest a functional shift in microbiota occurred over the course of the invasion process. While high variability in microbiota at the local scale supports A. vermiculophyllum to be a generalist host, we also identified a number of core taxa. These geographically independent holobiont members imply that cointroduction of specific microbiota may have additionally promoted the invasion process.

中文翻译：

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与入侵性海藻相关的微生物群在各个尺度上如何变化？

社区是由规模依赖的过程构成的。为了研究跨尺度的微生物群落的多样性和变异，侵入性和广泛传播的海藻Agarophyton vermiculophyllum提供了独特的机会。我们在整个北半球的已知分布范围内，对与这种全人类相关的真核和真核生物群落进行了表征。我们的数据表明，整个社区的社区组成和多样性不仅在当地，而且在更大的地理尺度上都不同。虽然在地方尺度上（即在人口内部）起作用的过程是相关微生物群落的主要结构驱动因素，但群落组成的变化还取决于在更大地理尺度上起作用的过程。有趣的是，最大的分析量表（即天然和非天然范围）解释了预测的功能基团的流行率变化，这可能表明微生物群的功能转移是在入侵过程中发生的。A. vermiculophyllum是一名多面手寄主，我们还确定了一些核心类群。这些地理上独立的整体类成员暗示特定微生物群的共引入可能进一步促进了入侵过程。