The Ordovician Radiation was among the most extensive intervals of diversification in the history of life. However, a delineation of the proximal cause(s) of the Radiation remains elusive. Any such determination should involve an analysis of geographic overprints on diversification: did the Radiation occur randomly around the world or, alternatively, was it focused in particular geographic or depositional regimes? Here, I present a comparative evaluation of Ordovician diversification among several palaeocontinents to determine whether biotas associated with certain palaeocontinents exhibited different diversification patterns than others; in part, this involves a numerical "correction" to raw diversity trajectories. Clear disparities among palaeocontinents are indicated by the data, which appear to reflect differences in the extent of siliciclastic input partly in association with tectonic activity. Further testing will be required to fully substantiate the implication that siliciclastic influx was a predominant factor in the Ordovician Radiation, affecting a variety of higher taxa among all three Phanerozoic evolutionary faunas.

中文翻译：

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奥陶纪辐射期间古大陆之间比较多样化的动态。

奥陶纪辐射是生命史上最广泛的多样化区间之一。但是，对辐射的近端原因的描述仍然难以捉摸。任何此类确定都应包括对多样化方面的地理叠印的分析：辐射是否在世界范围内随机发生，或者是集中在特定的地理或沉积制度上？在这里，我对几个古大陆之间的奥陶纪多样性进行了比较评估，以确定与某些古大陆相关的生物群是否表现出与其他古生物不同的多样性模式。在某种程度上，这涉及对原始多样性轨迹的数字“校正”。数据表明古大陆之间存在明显的差异，这似乎反映了与构造活动有关的硅质碎屑输入范围的差异。将需要进一步测试，以充分证实硅质碎屑涌入是奥陶纪辐射的主要因素，影响到所有三个古生代进化动物群中的各种较高的分类单元。