The world’s population has more than doubled since 1960. During that same period, global wildlife populations, according to the World Wildlife Fund and other sources, have fallen by nearly 70 percent.

Most people know only two things about the appendix: You don’t need it – and if it bursts, you need surgery fast. That basic story traces back at least to Charles Darwin, the English naturalist who ...

Wild orcas across four continents have repeatedly floated fish and other prey to astonished swimmers and boaters, hinting that the ocean’s top predator likes to make friends. Researchers cataloged 34 ...