The genus Cannabis (family Cannabaceaea), first appeared in Central asia somewhere around 34 million years ago. Evidence points to a coevolutionary symbiotic relationship between mankind and cannabis, with human selective breeding being responsible for the diverse range of plant chemovars that we have today.
Cannabis is considered to be a one-species genus by most, Cannabis sativa l. In 1785 on an expedition to India, Jean-Baptiste Lamarck published a description of a second variety that he encountered and named ‘Cannabis indica’, to describe the short, squat, conifer shaped cannabis plants with wide leaves.
In 1974, Cannabis was recognised by Richard Evans Schultes as 4 distinct species, Cannabis sativa, Cannabis indica, Cannabis spontanea and Cannabis ruderalis. In 2004, after analysing 157 cannabis samples from 26 different countries, Karl Hillig, concluded that there are 2 distinct gene pools of Cannabis, sativa and indica, containing 7 biotypes.
Despite the wide variety of Cannabis indica chemovars available, the gene pool is narrower than that of Cannabis sativa, suggesting a founder effect may have bottlenecked the genetic base of Cannabis indica. Until recently it had been assumed that the segregation was caused by a either geographical event such as an ice-age glacation, or the advent of human selection pressure. After creating the worlds first cannabis chromosome map, researchers at the University of Toronto found it was a viral attack on the cannabis genome millions of years ago that caused a gene duplication which split ancient Cannabis to split into 2 distinct types, sativa and indica.
While these 7 biotypes may not sound familiar compared with how ‘Sativa’ and ‘Indica’ are used in the current vernacular, we feel its important to inform of the correct taxonomical definitions to enable further research.