While knowledge of natural remedies gets handed down from one generation to the next, you have to wonder about the first person to try opium, peyote, or coffee. Well, we know about coffee, which was consumed after a goat herder saw how it affected his flock. Maybe we picked up other remedies from the animal kingdom. Yes, animals have their own medicine, in a phenomenon called zoopharmacognosy.
The range of animals known to make use of medicinal materials is amazingly broad. To qualify as self-medication, the ingested material should not be part of the regular diet and should provide no known nutritional value. Dog lovers may be familiar with grass-eating, when our canine friends seek to soothe an upset stomach by eating indigestible plant material to induce vomiting. Other examples include certain types of parrots and macaws that eat clay to aid digestion. Some lizards feed on particular roots to help counteract snake venom. Pregnant lemurs have discovered the lemur version of prenatal vitamins, chewing particular leaves to aid milk production, labor, and reduce parasites. Brazilian spider monkeys take fertility-enhancing or contraceptive plants. Nor does self medicating need to be natural. Sparrows have been known to integrate cigarette butts into their nests, having somehow discovered that the nicotine residue impedes parasitic mites.