When we think about self-medication, we usually visualize humans taking over-the-counter drugs like antihistamines for allergies or Pepto-Bismol for diarrhea.
A new paper in the journal Science suggests we should take a broader view. Many different types of animals have been found to select foods or nest materials that help to reduce parasites. This includes such unlikely behaviors as house sparrows adding cigarette butts to their nests to limit the numbers of mites infesting their young.
Creatures as close to humans as baboons and chimpanzees and as far as butterflies and honeybees appear to be selecting certain foods to reduce parasites and improve health. These examples demonstrate that an animal does not need a complex learning strategy to be able to self-medicate.