Toward a predictable cask theory of species extinction assessment in the Anthropocene

Predicting species extinction is challenging in the context of climate change. The International Union for Conservation of Nature (IUCN) Red List of Threatened Species assesses species extinction risk by accounting for population size and global range of taxa, but this approach neglects the importance of genetic variability. Here, we propose a life strategy index (LSI) for predicting the extinction risks of species under climate change. The LSI is composed of three fundamental and independent components: namely, evolutionary potential, ecological potential, and colonization potential. The LSI constitutes a so-called “cask” theory of species extinction, which predicts that extinction likelihood is determined by the relative deficiency of any of the three components. The indicative variables used to construct the proposed LSI make the index applicable to assessments of (and predictions for) the extinction risk of different taxa in the face of climate change, which can inform management and conservation of imperiled species in a more scientific and precise manner.