A large brachiopod fauna collected through the upper Wanyaoshu Formation (middle Hirnantian), West Yunnan, China displays, for the first time, a vertical transition within the Hirnantia fauna. The inner to mid‐shelf Fardenia–Hirnantia association segues into the deeper water Aegiromena–Anisopleurella association during the Metabolograptus persculptus marine transgression. This transition parallels the pattern apparent in onshore–offshore gradients within the Hirnantian, imitating Walther’s Law for facies, instead predicting the seaward transitions between community types within a single transgressive sequence. In addition, large‐sized brachiopods such as Hirnantia and Eostropheodonta become rarer and small‐sized brachiopods, for example, Aegiromena and Anisopleurella more common. It is a rare opportunity to view transformations in community composition and structure within the Hirnantia fauna together with changes in both the size of individuals and populations (from large to small) during the transgression.

中文翻译：

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从浅水到深水：Hirnantia brachiopod动物区系（晚奥陶纪）的生态学研究及其全球意义

通过云南西部的万瑶书组上部（黑南天中部）采集的大型腕足动物区系，首次在Hirnantia动物区内显示出垂直过渡。内到货架中旬Fardenia -赫南特贝协会继续入深水Aegiromena - Anisopleurella期间协会Metabolograptus persculptus海侵。这种转变与赫南特人在陆上-近海梯度中出现的模式相似，模仿了岩相的沃尔瑟定律，而不是预测单个海侵序列中群落类型之间的向海过渡。此外，大型腕足动物如Hirnantia腕足类和食管蛇类变得更稀有，例如小节肢动物和棘足动物更常见。这是一个难得的机会，可以了解海兰提亚动物群内社区组成和结构的转变，以及在犯罪过程中个体和种群大小的变化（从大到小）。