FEVR X SUNBATHING

Fever is so important for slaying germs that animals that cannot regulate their own body temperature—for example, locusts, baby rabbits, and coldblooded creatures like lizards—have found alternative means to cook pathogens: They sunbathe. Lest anyone doubt that sickness behavior is a defense against pathogens, scientists can induce it without exposing animals to a single germ. They manage this simply by injecting healthy rodents with immune components called cytokines. The once-frisky animals refuse to eat or drink and lose their passion for running in their wheels. Up go their temperatures and down go their heads. They act and feel sick even though they’re healthy