Take a globe-circling tour of our endangered planet with conservation biologist Stuart Pimmwho is taking stock and keeping score. We use 50 percent of the world

Humans use 50 percent of the world's freshwater supply and consume 42 percent of its plant growth. We are liquidating animals and plants one hundred times faste

Why "the balance of nature"? Resilience. Temporal variability and the individual species. The effects of food-web structure. The variability of the environment.

As humanity presses down inexorably on the natural world, people debate the extent to which we can save the Earth's millions of different species without sacrif

Food webs are diagrams depicting which species interact or in other words, who eats whom. An understanding of the structure and function of food webs is crucial