According to the bottom-up theory of how ecosystems are structured, the availability of edible plants is what primarily determines an ecosystem' s characteristics since it determines how many herbivores the ecosystem can support, which in turn determines how many predators it can support
This theory also holds that a reduction in the number of predators will have little impact on the rest of the ecosystem
After hunting virtually eliminated predators on Rigu Island, the population of many herbivore species increased more than tenfold, causing the density of plants to be dramatically reduced.