Cannabis, also known as hemp or marijuana, evolved about 28 million years ago on the eastern Tibetan Plateau, according to a pollen study published in May. A close relative of the common hop found in beer, the plant still grows wild across Central Asia.

Where did weed first grow?

A 2016 study by other scientists said that the earliest records for cannabis were mostly from China and Japan, but most botanists believe that it was probably first domesticated in the eastern part of Central Asia, where wild varieties of the plant are widespread.

What is the oldest weed in the world?

Nearly two pounds of still-green plant material found in a 2,700-year-old grave in the Gobi Desert has just been identified as the world's oldest marijuana stash, according to a paper in the latest issue of the Journal of Experimental Botany.