Tillotoma Foundation

Tusheema Dutta || Research Associate (Natural Sciences, Science Policy & Ayurveda) 

The Tanzanian medicine man, Babu Kalunde, discovered an effective cure nearly a century ago that saved the lives of many in his village who were suffering from a dysentery-like disease outbreak. By watching a similarly ill young porcupine ingesting the plant's roots, he learned about the possible medicinal value of a plant known to the WaTongwe as mulengelele. Babu Kalunde and the inhabitants of his village had avoided this plant before these timely discoveries, which they understood to be extremely poisonous. However, after showing the villagers his tale of the porcupine and taking small doses of the herb himself, he convinced them to use the sick plant. The WaTongwe utilize the roots as medicine to this day. Mohamedi Seifu Kalunde, the grandson of Babu, now a revered elder and healer himself, uses this herb to cure gonorrhea and syphilis as well. 

Scientists are latecomers to studying animal self-medication and its potential applications to western medicine, contrasted with Babu. However, a growing body of scientific data in favour of animal self-medication, or zoopharmacognosis, has been obtained in recent years. Mohamedi has collaborated with a growing community of colleagues to study how chimpanzees in the wild cope with parasites and what their actions can teach us about the treatment of other diseases, beginning with chance observations of a sick chimpanzee in 1987 (Huffman and Seifu 1989). 

The secondary compounds in a plant, unnecessary for feeding, development, or reproduction, have evolved to defend against insects and mammalian predators. While ecologists are researching the behaviour of animal foraging concentrate on how animals interact with these secondary compounds in their diet (Freeland and Janzen 1974, Glander 1975, 1982, Hladik 1977, Janzen 1978, Wrangham and Waterman 1981), zoopharmacognosy's fundamental concept is that animals use these secondary compounds to medicate themselves. We are interested in translating these lessons in evolutionary medicine into clinical use for humanity from a more comprehensive viewpoint (Huffman and Seifu 1989, Ohigashi et al. 1994, Plotkin 2000).

A variety of secondary compounds comprises much of the plant material eaten by animals in the wild. Johns (1990) suggests that the non-nutritional chemicals typically found in our primate ancestors' diets were replaced by natural drugs and synthetic pharmaceuticals used by humans today. In this context, it is worth researching in more depth the non-nutritive components of products eaten by African great apes, and indeed, all primates, for hints to the therapeutic benefits that such a diet can afford.

The distinction between diet and medicine may not always be evident in traditional human cultures. This idea is expressed in a Japanese saying, "ishoku dougen" which means "medicine and food are of the same origin." It is perhaps no coincidence, then, that traditional spices, condiments, and vegetables used worldwide are also essential sources of anti-tumour agents or have antioxidant, antibacterial, antiviral, and antiparasitic characteristics. 

The concept of food as medicine goes a step further. Etkin (1996) found that as medicine, 30 percent of the plant species known as food among Nigeria's agricultural Hausa were also used. In comparison, 89 percent of the organisms used to relieve malaria symptoms were still used in a nutritional sense (Etkin and Ross 1983). Etkin and Ross (1994) say that many Hausa foods were first derived from non-cultivated plants first used as medicine.

One of the difficulties in understanding animal self-medication is to differentiate between (a) the potential indirect medicinal benefits obtained from secondary plants that are rich in compounds, possibly due to their nutritional value, and (b) the restricted, situation-specific intake of products that are only processed for their medicinal properties. Great apes' findings offer the most transparent empirical data to date regarding overt ways of animal self-medication. The theory that is currently being explored is that these habits help regulate intestinal nematodes and tapeworms or provide relief from, or both, associated gastrointestinal upset.

Because of their phylogenetic closeness and shared neuronal mechanisms of chemosensory detection, humans and chimpanzees learn to associate and choose related products in medicinal plants while exhibiting similar disease symptoms. The evolution of medical habits from the great apes to early hominids to modern humans has profound consequences for modern medicine, unquestionably.