Why they eat their own.

• Position: Science - Brief Article

Scientists have discovered that bacteria practice cannibalism, adding the tiny organisms to the list of beings, including birds, flies and chimpanzees, that sometimes eat their own kind. Their reasons vary, according to researchers. When humans practice cannibalism, generally it's for complex psychological reasons, such as appeasing gods or honoring ancestors.

For chimpanzees it seems to be an act of revenge or malice, while for lions, the explanation is genetic preservation: When a male takes over a pride, he eats the previous king's cubs, thereby eliminating the old royal bloodline. The motivation praying mantises remains unclear: As the finale to a successful copulation, the female bites off her mate's...