Cannabis is everywhere: today, the plant grows on every continent except Antarctica. But that wasn’t always the case. So how did this “weed” come to take over the world?
Its success is due in large part to us. The evidence suggests that cannabis first evolved nearly 28 million years ago on the Tibetan plateau, after splitting off from the last common ancestor it shared with the hop plant. At first, early humans may have unwittingly spread it. By clearing vegetation for settlements and heaping food scraps in waste dumps, they gave cannabis what it needed to thrive: open, sunny areas with fertile soil. That is why some scientists refer to the plant as a weedy “camp follower”.
In time, humans came to appreciate the many uses of the cannabis plant, and it is believed to be one of the first plants we cultivated when we began farming around 12,000 years ago. The stalks could be dried to create fibres, the seeds could be eaten or used to make oil and the resin-coated bracts could have been used for their medicinal and mind-altering purposes (though evidence for the latter is much more recent).
The plant’s utility enabled its spread and humans became the most important agent for its dispersal.
POUR LIRE LA SUITE: New Scientist
