[On the evolution of virulent viruses in bats]. / Darwinistisch speculeren over virulente virussen van vleermuizen.

Ideas about the 'evolution of virulence' postulated by Paul Ewald are used to explain why bats, more often than other mammals, are a reservoir of virulent viruses, and why many of these viruses severely affect other mammals, including humans, whereas they appear to be non-pathogenic for bats.