It has long been known that cannabis plants are native to Central Asia. A new study, however, provides a new focus on where exactly this genus could have come from millions of years ago.
Medieval records show that humans have hypothesized about the geographical origin of cannabis for over a thousand years, with the famous Arabic polymath Ibn Wahshiyya proposing India or perhaps China as early as 930 AD.
However, the rarity of printed fossils (impressions of leaves on other objects) in historical records has made it difficult for the research community to identify anything more specific than Central Asia, although cannabis is currently booming in many areas of science and scientific research.
"Despite extensive literature emerging in the last three decades, the classification of cannabis and its origin is still under discussion," a team led by first-year author and medical researcher John McPartland of the University of Vermont said new release.
To overcome the lack of printed fossils, scientists turned to pollen from plants of the genus cannabis . These pollen were studied for the first time since the 1
In recent decades, numerous fossil pollen studies have been conducted to identify ancient records of the plant throughout Asia and elsewhere, including determining where it thrives best.
"Cannabis thrives in the steppe – an open, treeless habitat," the researchers write.
In the new study, McPartland and his team reviewed 155 existing fossil pollen studies focusing on Asia. One of the difficulties with the data is that many of these studies mix pollen grains with those of plants of the genus Humulus. They look similar, considering that both plants differed about 28 million years ago.
To circumvent the identification problems, the researchers used a statistical method involving "ecological proxies" in which they are likely to pollute the pollen to other differentiated plants common in the region, including plants of the genus Artemisia Artemisia [Art.
Based on available evidence, the results suggest what the most likely geographical origin of cannabis is – even if this could be a hypothesis impossible to prove.
"We have bridged the time gap between the departure date and the oldest pollen by mapping the earliest occurrence of Artemisia ," writes the team The Northeastern Tibetan Plateau, which we call the Origin Center of Cannabis , is located near Qinghai Lake.
After that, the team believes that cannabis is spreading westward and reaches Russia and Eur. About 6 million years ago – and to the east, 1.2 million years ago to eastern China.
This spread made various Cannabis plants are available for cultivation to people throughout Eurasia and it is no wonder that we quickly recognized the various properties of hemp – from mind-altering agents to fibers for ropes and clothing.
The results are published in Vegetation History and Archaeobotany reported.