How much space does nature need? 30 percent of the planet may not be enough

Nature needs to be protected, scientists agree, but how best to do it is up for debate

Amazon logging

Habitat loss and such human encroachment as this clear-cutting in the Amazon (shown) are a major threat to biodiversity worldwide. The United Nations is drafting an ambitious new set of conservation targets to safeguard species and prevent further losses.

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For millions of years, giants graced the murky depths of China’s Yangtze River.