Takeover consists in diverting some fraction of the earth’s life-supporting capacity from supporting other kinds of life to supporting our kind. Our pre-Sapiens ancestors, with their simple stone tools and fire, took over for human use, organic materials that would otherwise have been consumed by insects, carnivores or bacteria. From about 10,000 years ago, our earliest horticulturalist ancestors began take over land upon which to grow crops for human consumption. That land would otherwise have supported trees, shrubs or wild grasses and all the animals dependent thereon — but fewer humans. As the expanding generations replaced each other, Homo sapiens took over more and more of the surface of this planet, essentially at the expense of its other inhabitants.

~ William R. Catton Jr. (1926-01-15 age:92) Author of Overshoot: The Ecological Basis of Revolutionary Change. ,

From the point of view of the other species on earth, we humans are as welcome as Viking invaders or pancreas cancer.