Pests are species that, when they become overabundant, have unacceptable effects on humans. Ironically, humans themselves have greatly increased their abundance in the last century. Although this increase, together with concomitant scientific and economic growth, has brought many benefits, it also imposes great costs on ecosystems. Lands, waterways, the atmosphere and biodiversity are all greatly affected at both local and global scales. In fact, current human demands exceed Earth's renewable productive capacity, an inherently unsustainable situation. Consequently, achieving humanity's overarching goals of universal human wellbeing and ecological sustainability is not occurring. Indeed, it is becoming increasingly improbable since much more population and economic growth is certain. Since, humans depend totally on healthy, functioning ecosystems, this situation is unacceptable; humans have become a pest species. Moreover, because of their pervasive negative effects on other species and ecosystems, humans can be considered the ultimate pest.