Fossils are the only remaining evidence of the majority of species that have ever existed, providing a direct window into events in evolutionary history that shaped the diversification of life on Earth. Phylogenies underpin our ability to make sense of evolution but are routinely inferred using only data available from living organisms. Although extinct taxa have been shown to add crucial information for inferring macroevolutionary patterns and processes (such as ancestral states, paleobiogeography and diversification dynamics), the role fossils play in reconstructing phylogeny is controversial. Since the early years of phylogenetic systematics, different studies have dismissed the impact of fossils due to their incompleteness, championed their ability to overturn phylogenetic hypotheses or concluded that their behavior is indistinguishable from that of extant taxa. Based on taxon addition experiments on empirical data matrices, we show that the inclusion of paleontological data has a remarkable effect in phylogenetic inference. Incorporating fossils often (yet not always) induces stronger topological changes than increasing sampling of extant taxa. Fossils also produce unique topological rearrangements, allowing the exploration of regions of treespace that are never visited by analyses of only extant taxa. Previous studies have proposed a suite of explanations for the topological behavior of fossils, such as their retention of unique morphologies or their ability to break long branches. We develop predictive models that demonstrate that the possession of distinctive character state combinations is the primary predictor of the degree of induced topological change, and that the relative impact of taxa (fossil and extant) can be predicted to some extent before any phylogenetic analysis. Our results bolster the consensus of recent empirical studies by showing the unique role of paleontological data in phylogenetic inference, and provide the first quantitative assessment of its determinants, with broad consequences for the design of taxon sampling in both morphological and total-evidence analyses.

中文翻译：

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死亡在我们身边：古生物学数据极大地修改了系统发育假说

化石是大多数曾经存在过的物种的唯一剩余证据，它提供了一个直接窗口，可以直接了解进化史上塑造地球生命多样化的事件。系统发育是我们理解进化的能力的基础，但通常仅使用来自活生物体的数据进行推断。尽管已证明已灭绝的分类群可以为推断宏观进化模式和过程（例如祖先状态、古生物地理学和多样化动态）增加关键信息，但化石在重建系统发育中的作用仍存在争议。自系统发育系统学的早期以来，由于化石的不完整性，不同的研究已经驳回了化石的影响，支持他们推翻系统发育假设的能力，或者得出结论，他们的行为与现存分类群的行为没有区别。基于对经验数据矩阵的分类群添加实验，我们表明古生物学数据的包含在系统发育推断中具有显着效果。与增加现存分类群的采样相比，加入化石通常（但并非总是）会引起更强烈的拓扑变化。化石还产生独特的拓扑重排，允许探索仅通过分析现存分类群从未访问过的树空间区域。先前的研究已经对化石的拓扑行为提出了一套解释，例如它们保留了独特的形态或它们折断长枝的能力。我们开发的预测模型表明，拥有独特的特征状态组合是诱发拓扑变化程度的主要预测因素，并且可以在进行任何系统发育分析之前在一定程度上预测分类群（化石和现存）的相对影响。我们的结果通过显示古生物学数据在系统发育推断中的独特作用支持了最近的实证研究的共识，并提供了对其决定因素的首次定量评估，对形态学和总体证据分析中的分类群抽样设计产生了广泛的影响。