exotic species, definition of

Greenhouse gases are those gaseous constituents of the atmosphere, both natural and anthropogenic, that absorb and emit radiation at specific wavelengths within the spectrum of thermal infrared radiation emitted by the Earth’s surface, the atmosphere itself, and by clouds. This property causes the greenhouse effect.

Greenhouse gases are essential to maintaining the current temperature of the Earth; without them the planet would be uninhabitable.

Wikipedia Entry

• Invasivores Exercise Eradication by Mastication in the Fight Against Exotic Species
  “It feels good to eat your enemies,” says Andrew Deines, a postdoctoral researcher at Michigan State University, who studies the ecology of invasive organisms...