Abstract：
There is no scientific consensus about whether and how species\' evolutionary age, or the elapsed time since their origination, might affect their probability of going extinct. Different age-dependent extinction (ADE) patterns have been proposed in theoretical and empirical studies, while the existence of a consistent and universal pattern across the tree of life remains debated. If evolutionary age predicts species extinction probability, then the study of ADE should comprise the elapsed time and the ecological process acting on species from their origin to their extinction or to the present for extant species. Additionally, given that closely related species share traits associated with fitness, evolutionary proximity could generate similar ADE patterns. Considering the historical context and extinction selectivity based on evolutionary relatedness, we build on previous theoretical work to formalize the Clade Replacement Theory (CRT) as a framework that considers the ecological and evolutionary aspects of species age and extinction probability to produce testable predictions on ADE patterns. CRT\'s domain is the diversification dynamics of two or more clades competing for environmental space throughout time, and its propositions or derived hypotheses are as follows: (i) incumbency effects by an early arriving clade that limit the colonization and the diversification of a younger clade leading to a negative ADE scenario (younger species more prone to extinction than older ones) and (ii) an ecological shift triggered by an environmental change that imposes a new selective regime over the environmental space and leads to a positive ADE scenario (extinction probability increasing with age). From these propositions, we developed the prediction that the ADE scenario would be defined by whether an ecological shift happens or not. We discuss how the CRT could be tested with empirical data and provide examples where it could be applied. We hope this article will provide a common ground to unify results from different fields and foster new empirical tests of the mechanisms derived here while providing insights into CRT theoretical structuration.
摘要：
关于物种是否以及如何进化年龄，没有科学共识，或者自它们起源以来过去的时间，可能会影响它们灭绝的概率.在理论和实证研究中提出了不同的年龄依赖性灭绝(ADE)模式，而在整个生命之树中是否存在一致和普遍的模式仍然存在争议。如果进化年龄预测物种灭绝的可能性，然后，对ADE的研究应包括从起源到灭绝或现存物种到现在对物种起作用的时间和生态过程。此外,鉴于密切相关的物种具有与适应性相关的特征，进化接近可以产生类似的ADE模式。考虑到基于进化相关性的历史背景和灭绝选择性，我们在先前的理论工作的基础上，将进化枝替代理论（CRT）形式化为一个框架，该框架考虑了物种年龄和灭绝概率的生态和进化方面，以对ADE模式进行可测试的预测。CRT的领域是两个或多个进化枝在整个时间内竞争环境空间的多样化动态，及其命题或得出的假设如下：（i）早期到达的进化枝的在职效应限制了年轻进化枝的殖民和多样化，从而导致负面的ADE情景（年轻物种比年长物种更容易灭绝）和（ii）由环境变化引发的生态转变，对环境空间施加了新的选择性制度，并导致积极的ADE情景（灭绝概率随年龄增长而增加）。从这些命题中，我们预测ADE情景将由是否发生生态转变来定义。我们讨论了如何使用经验数据对CRT进行测试，并提供了可以应用的示例。我们希望本文将提供一个共同点，以统一来自不同领域的结果，并促进对此处得出的机制进行新的实证检验，同时提供对CRT理论结构的见解。
