The popularity of cannabis is nothing new, but a new study finds it dates back further than many may have expected. How much further back? Try 12,000 years.

That’s the time period identified in a new study published in the journal Science Advances. The study also pinpoints a place: East Asia.

The international team of researchers, led by co-authors from Switzerland and China, wrote that through genome sequencing they “show that sativa was first domesticated in early Neolithic times in East Asia and that all current hemp and drug cultivars diverged from an ancestral gene pool currently represented by feral plants and landraces in China.”

The researchers wrote that these ancient people in what is now China likely used the plant for fiber and medicinal purposes. Breeding cannabis to get high didn’t happen until about 8,000 years later.

The New Study Differs From Past Efforts to Pinpoint The Origins of Cannabis

The findings of the study differ from previous research that placed the origin of hemp and cannabis in Central Asia. It’s an area where people 2,500 years ago used cannabis as part of a ritualistic funeral ceremony.

The new research argues that most people place cannabis’ origins in Central Asia because it’s possible even today to find wild plants – called feral plants – growing there. However, the new study suggests these feral plants descended from domesticated plants that cross pollinated with wild plants at some point thousands of years ago.

In the study, researchers also pointed out that the change in attitude toward cannabis is a 20th century thing. They wrote: “As one of the first domesticated plants, it has a long and fluctuating history interwoven with the economic, social, and cultural development of human societies.” They noted that cannabis served as a “major source for textiles, food, and oilseed,” but those used declined in the 20th century as the focus switched to its use as a recreational drug.

Researchers Sequenced 82 New Genomes for The Study

To determine the origins of cannabis, researchers spent four years gathering 110 different cannabis varieties from around the world. They included Switzerland, China, India, Pakistan and Peru. They also obtained samples from commercial cannabis growers and botanical collections.

Scientists used this collection of seeds, leaves and plant material to sequence 82 new genomes, then combined them with 28 genomes already publicly available. They then analyzed the vast amount of genetic information from the plants to figure out the evolutionary relationship between them, according to Smithsonian magazine.

They found that feral plants from East Asia more closely resemble the plant ancestors of cannabis than the varieties grown today.

The research also indicated that wild cannabis split off from domesticated varieties about 12,000 years ago. That means cannabis was part of a boom in farming innovation during that time period in East Asia, including the beginning of planting rice, corn, soybean, apricots and peaches.

They also found the psychoactive strains of cannabis diverged about 4,000 years ago, when farmers in Europe and the Middle East began breeding the plant specifically for its mind-altering properties.