"Human activities in tropical forests are disruptive processes and can trigger numerous, yet not completely understood, mechanisms or effects which will in turn alter, in a more or less significant way, the overall function, structure and composition of the ecosystem.
"Plant regeneration (loss of pollinators, seed dispersers and seed predators), food webs (loss of top predators or of their prey), and plant diversity (change in herbivory patterns, increased pests) are amongst the various processes dependent upon the presence of wild fauna. Some species or functional groups matter more than others in maintaining ecosystem processes and integrity. “Keystone species”, “ecosystem engineers” or organisms with high “community importance values” refer to species whose loss has a disproportionate impact on the ecosystem when compared to the loss of other species. Conventional wisdom predicts that the reduction or extirpation of these animals will result in dramatic changes to the ecosystems..."