A sacred Indian plant may have crossed from the Americas before Columbus
Datura metel is offered to Shiva in Hindu worship and fills ancient Ayurvedic texts. Yet botanists now think it is not a true species but a set of old cultivars bred from a Caribbean plant, and that it reached India no later than the second century CE, long before Columbus sailed.
Datura is a genus of night-flowering nightshades with trumpet-shaped blooms and spiny seed capsules, known in English as thornapple, jimsonweed or devil's trumpet. The genus name comes via Hindi from the Sanskrit for white thorn-apple, while jimsonweed is a slurred form of Jamestown-weed, the name a Virginian colonist, Robert Beverley Jr., gave it. In Mexico it is toloache, from a Nahuatl phrase meaning the plant with the nodding head. Mexico is regarded as the genus's centre of origin, and species once assumed native to China, Australia and Africa or Asia are now suspected to be early introductions.
Pinning down species is notoriously hard. The same plant can become an 80 cm bush in damp half-shade or a spindly 13 cm stem in dry ground, and many new species turn out to be local varieties that vanish from the lists within years. Specialists Ulrike and Hans-Georg Preissel accept nine species, while Kew's database lists fourteen. One genuine newcomer, D. arenicola, described in 2013, was distinctive enough to get its own section; its name means sand-loving.
Every part of every species is poisonous and mind-altering, especially seeds and flowers, which carry the tropane alkaloids scopolamine and atropine. Strength varies with the plant's age, location and weather, which makes it exceptionally dangerous. A traditional mnemonic sums up the poisoning by likening the victim to a bat for blindness, a hatter for madness, a beet for flushing and a bone for dryness. It belonged with henbane, mandrake and deadly nightshade among the classic witches' weeds used in European potions, and some Native American groups used it ritually as an entheogen, relying on deep traditional knowledge to limit harm.
Poisonings still happen by accident. The CDC recorded a family of six hospitalised after Datura ended up in a stew, and honey made by certain wasps that gather its nectar can be toxic during the flowering season. Between 1950 and 1965, state laboratories in Agra investigated 2,778 deaths from eating it. Long-term use of anticholinergic substances like these also appears to raise dementia risk markedly.
Source: Datura
