Yea, just wait till some cornerstone species give way. If enough of the ecosystems get damaged there will be hell to pay.
http://en.wikipedia.org/wiki/Extinction_event
Its estimated that 99% of all previous species are currently extinct.
Present day — [Holocene extinction event] ... Some, such as E. O. Wilson of Harvard University, predict that humanity's destruction of the biosphere could cause the extinction of one-half of all species in the next 100 years. ... The extinction of many megafauna near the end of the most recent ice age is also sometimes considered part of the Holocene extinction event. Some paleontologists, however, question whether the available data supports a comparison with mass extinctions in the past.
65 million years ago (Ma) — at the Cretaceous-Paleogene transition ...about 17% of all families and 50% of all genera went extinct. (75% species)...
205 Ma — at the Triassic-Jurassic transition (the Triassic-Jurassic extinction event) about 20% of all marine families (55% genera) as well as most non-dinosaurian archosaurs, most therapsids, and the last of the large amphibians were eliminated. 23% of all families and 48% of all genera went extinct.
251 Ma — at the Permian-Triassic transition, Earth's largest extinction (the P/Tr or Permian-Triassic extinction event) killed 53% of marine families, 84% of marine genera, about 96% of all marine species and an estimated 70% of land species (including plants, insects, and vertebrate animals). 57% of all families and 83% of all genera went extinct.[6]. The "Great Dying" had enormous evolutionary significance: on land it ended the dominance of mammal-like reptiles and created the opportunity for archosaurs and then dinosaurs to become the dominant land vertebrates; in the seas the percentage of animals that were sessile dropped from 67% to 50%. The whole late Permian was a difficult time for at least marine life — even before the "Great Dying".
360-375 Ma — Late Devonian extinction. Near the Devonian-Carboniferous transition at the end of the Frasnian Age in the later part(s) of the Devonian Period. A prolonged series of extinctions eliminated about 70% of all species. ...19% of all families of life and 50% of all genera went extinct.
440-450 Ma — at the Ordovician-Silurian transition two Ordovician-Silurian extinction events occurred, and together are ranked by many scientists as the second largest of the five major extinctions in Earth's history in terms of percentage of genera that went extinct. 27% of all families and 57% of all genera went extinct.
488 Ma — a series of mass extinctions at the Cambrian-Ordovician transition (the Cambrian-Ordovician extinction events) eliminated many brachiopods and conodonts and severely reduced the number of trilobite species.
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Mass extinction is built into evolution. It clears out the deadwood and lets new species give it a go.
