It's common scientific wisdom that parasite resistance comes from repeated exposure to a parasite. But a new study has turned this idea on its head. Guppies who were removed from rivers swarming with parasites actually evolved an improved parasite tolerance in just a few generations. Here's how it happened.
Many parasites are satisfied with just living off of their hosts, while others decide their hosts must die. But there are also some parasites who can change their hosts' behavior or physiology in ways fit only for science fiction. Here are 12 parasites who manipulate their hosts in incredible ways.