It was, Charles Darwin wrote in 1879, "an abominable mystery".
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Unique? Suni was much more than that. He was vital to the survival of his kind.
Pope Francis called for more respect for nature on Saturday, branding the destruction of South America's rain forests and other forms of environmental exploitation a sin of modern times.
Cornered by fishermen, divers and boats, the bottlenose dolphins splashed frantically as they tried to escape their human captors in the infamous cove in Japan.
There are about 1,700 tigers left in the wild in India. In the past five weeks, 17 people in four states have been killed by tigers.
Today, McDonald’s announces that it will begin purchasing verified sustainable beef in 2016