A tongue twister isn’t it? And you are sure GT borrowed it from Harry Potter? Actually the word has Greek roots – zoo means animal; pharma is drug and cognosy is ‘to recognise.’
Ancient folklores tell of animals curing themselves. Many go out of their way, when they are ill, to find natural substances not part of their diet. Scientists were keen to know how animals cure diseases. And a new branch of study called Zoopharmacognosy was born. So how do animals treat or prevent diseases?
Plants are medicinal and European starlings in North America know this well. These birds like to line their nests with leaves of wild carrot, yarrow and fleabane because these aromatic plants control mites. Chicks in nests lined with wild carrot leaves have higher hemoglobin levels than those in nests without it. This is because they lose less blood to mites. In Kolkata, house sparrows bring neem (Azidiachta indica) leaves to line nests which is a popular insecticide used by people.
Many insects make toxins and other species use these. Songbirds wipe ants on their plumage. They roll in anthills and allow the ants to crawl through their feathers during the ‘anting’ behaviour and the ants they choose spray formic acid. Did you know that beekeepers also use formic acid to control parasitic mites in honeybees?
In Chinese folklore a farmer tried to kill a snake by beating it. The injured snake crawled into a clump of weeds and munched on them. This healed the wounds. The folklore may be an exaggeration, but the plant called Panex notoginseng is used in herbal formulations to stem external bleeding.
Giraffes, elephants and rhinoceroses eat clay-rich termite mound soil. Gorillas also mine clay-rich volcanic rock from under the exposed roots of ancient trees. Clay is an effective binding agent. Its chemical structure allows other chemicals to bond with it making it a powerful detoxifying agent. Clay is also the primary ingredient of kaolin found in many over-the-counter medicines to treat gastrointestinal diseases in humans.
Chimpanzees suffering from diarrhea in Tanzania pick shoots from a tree called Vernonia amygdalina, peel the bark and chew on it. They eat this with evident dissatisfaction but after 24 hours scientists noted that they had recovered completely. Interestingly, Vernonia amygdalina is known as the ‘bitter leaf tree’ among the WaTonge tribe of Tanzania. The plant has more than 25 known medicinal uses among people of sub-Saharan Africa for intestinal and parasitic ailments.
Animals have developed self-medication skills to survive and the process of natural selection has honed these. Many ethnic people have traditional techniques of treatment that seem to mimic ways used by the animals. Can modern medicine learn from them?