Theories of the Geographical Origin of Cannabis - South Asia
The great diversity of Cannabis varieties and extensive uses for Cannabis in northern India and Nepal, along the foothills of the Himalayas, implies that this region was one of the first areas where Cannabis was extensively utilized, if not the location of its first growth. Lineaus, who initially named Cannabis sativa when he established the binomial system of scientific nomenclature, believed Cannabis sativa to be native to India. However, he never collected specimens from this are and the notes on his herberium sheets are ambiguous.
Sharma argues that Cannabis originated in the valleys along the southern slopes of the Himalayas from Kashmir through Nepal, and Bhutan to Burma. Phenotypic diversity (the range of differences within one genotype) was the most important criterion in his conclusion. According to Sharma, Moslem traders most likely carried Cannabis west through the Elburz Mountains of Persia to the Middle East. Sea traders voyaging to the east coast of Africa spread drug types of Cannabis sativa to the west and to the east, and south through Burma, and on into Southeast Asia. The non-drug, hemp varieties of Cannabis sativa that spread north into Central Asia would have evolved at higher latitudes than their ancestors, the drug varieties, of lower (more southern) latitudes. Sharma argues that from Central Asia, the drug varieties moved west into Europe, and east along the Silk Road into China, with some drug types migrating far enough north where growing seasons were too short for the plants to produce psychoactive levels of THC. Sharma believes that the European and Chinese cultures has little interest in hashish use and made no effort to maintain psychoactive potency. Thus, these northern drug populations evolved into fiber types. Much later, these fiber varieties spread through trade to many parts o Eurasia.
