Extinction Cascades

The model connects this mechanism to top-down dietary ratcheting and the hypercarnivore ratchet in Pleistocene extinction discussions. Understanding extinct community disassembly requires attention to trophic-structure changes as megafauna are lost. The article proposes a feedback mechanism in which megaherbivore loss increases predation intensity on remaining large herbivores. Rising predation intensity can lower the threshold herbivore mass and push additional herbivore species below feasibility.