Data from: Origination, extinction, invasion, and extirpation components of the brachiopod latitudinal biodiversity gradient through the Phanerozoic Eon

The geographic distribution of brachiopod genus occurrences over the Phanerozoic shows that secular declines in origination and extinction rates were paralleled by increases in invasion and extirpation rates. Origination and extinction rates declined in two phases, the first from the Cambrian to latest Permian Periods and the second from the latest Permian Period to the present, which were accompanied by concomitant increases in invasion and extirpation rates. In addition to the temporal correlation, an inverse correlation was also weakly evident among time-averaged latitudinal gradients of rates. Compared with faunas at higher latitudes, low-latitude faunas experienced higher origination and extinction rates, and lower invasion and extirpation rates. We suggest that progressive increases in migration ability lowered origination and extinction rates because species that were better equipped to track a preferred habitat, for example, by the ability to disperse larvae over large distances, were less likely to evolve or become extinct in response to local environmental changes. The two phases were separated by the end-Permian mass extinction, which reset to high levels the origination and extinction rates of a taxonomically and ecologically altered global brachiopod fauna. Our data also allow us to quantify the relative contributions of origination, extinction, invasion, and extirpation to regional diversity (quantified as 10° latitudinal zones) more generally. Overall, invasion and extirpation explained slightly more variation in diversity than in situ origination and extinction. The four variables usually occurred in combinations that maintained rather than altered the shape of the latitudinal diversity gradient. For most of the Phanerozoic Eon, the gradient was not the product of continuous renewal, but rather existed as a holdover from a previous interval.

显生宙（Phanerozoic）腕足动物（brachiopod）属级出现记录的地理分布显示，起源速率（origination rate）与灭绝速率（extinction rate）的长期下降，与迁入率（invasion rate）和局地绝灭速率（extirpation rate）的上升呈同步趋势。起源与灭绝速率的下降分为两个阶段：第一阶段为寒武纪至晚二叠世，第二阶段为晚二叠世至今，这两个阶段均伴随迁入率与局地绝灭速率的同步上升。除时间相关性外，速率的时间平均纬度梯度之间还存在微弱的负相关关系。相较于高纬度动物群，低纬度动物群具有更高的起源与灭绝速率，以及更低的迁入与局地绝灭速率。我们提出，迁移能力的逐步提升降低了起源与灭绝速率：因为那些更善于追踪适宜生境的物种（例如具备长距离传播幼虫能力的物种），在响应局地环境变化时，演化或绝灭的可能性更低。这两个阶段以二叠纪末大灭绝（end-Permian mass extinction）为分界，该事件使得经历了分类学与生态系统重塑的全球腕足动物群的起源与灭绝速率恢复至高水平。我们的数据集还可更普适地量化起源、灭绝、迁入与局地绝灭对区域多样性（以10°纬度带为划分标准）的相对贡献。总体而言，迁入与局地绝灭对多样性变异的解释度略高于原位起源与灭绝。这四个变量通常以协同组合的方式维持而非改变纬度多样性梯度（latitudinal diversity gradient）的形态。在显生宙的大部分时间里，纬度多样性梯度并非持续更新的产物，而是源自先前时段的遗留状态。