School of Botany, University of Melbourne, Parkville, VIC 3010, Australia.
Conserv Biol. 2010 Jun;24(3):682-90. doi: 10.1111/j.1523-1739.2009.01398.x. Epub 2010 Jan 7.
Coextinction is a poorly quantified phenomenon, but results of recent modeling suggest high losses to global biodiversity through the loss of dependent species when hosts go extinct. There are critical gaps in coextinction theory, and we outline these in a framework to direct future research toward more accurate estimates of coextinction rates. Specifically, the most critical priorities include acquisition of more accurate host data, including the threat status of host species; acquisition of data on the use of hosts by dependent species across a wide array of localities, habitats, and breadth of both hosts and dependents; development of models that incorporate correlates of nonrandom host and dependent extinctions, such as phylogeny and traits that increase extinction-proneness; and determination of whether dependents are being lost before their hosts and adjusting models accordingly. Without synergistic development of better empirical data and more realistic models to estimate the number of cothreatened species and coextinction rates, the contribution of coextinction to global declines in biodiversity will remain unknown and unmanaged.
共灭绝是一种量化程度较低的现象，但最近的建模结果表明，当宿主灭绝时，依赖物种的丧失会导致全球生物多样性的大量损失。共灭绝理论存在关键的差距，我们在一个框架中概述了这些差距，以指导未来的研究，以便更准确地估计共灭绝率。具体来说，最关键的优先事项包括获取更准确的宿主数据，包括宿主物种的威胁状况；获取关于依赖物种在广泛的地点、生境和宿主与依赖者的范围上使用宿主的数据；开发能够纳入非随机宿主和依赖者灭绝相关因素（如系统发育和增加灭绝易感性的特征）的模型；以及确定依赖者是否在宿主之前消失，并相应地调整模型。如果不能协同开发更好的经验数据和更现实的模型来估计共同受到威胁物种的数量和共灭绝率，那么共灭绝对全球生物多样性下降的贡献将仍然未知和无法管理。
