HEMP IN HISTORY
Oldest evidence of cannabis use
discovered in 2500-year-old cemetery
in peaks of western China
Andrew Lawler
W
hen and where humans began to appreciate the
psychoactive properties of weed has been more a
matter of speculation than science.
Until now... A team led by archaeologists Yang Yimin and Ren Meng
of the Chinese Academy of Sciences in Beijing reports clear physical
evidence that mourners burned cannabis for its intoxicating fumes on
a remote mountain plateau in Central Asia some 2500 years ago.
The study, published today in Science Advances, relies on new
techniques that enable researchers to identify the chemical signature
of the plant and even evaluate its potency. "We are in the midst of a
really exciting period," says team member Nicole Boivin of the Max
Planck Institute for the Science of Human History (MPI-SHH) in Jena,
Germany. The paper is part of a wider effort to track how the drug
spread along the nascent Silk Road, on its way to becoming the global
intoxicant it is today.
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.
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A close relative of the common hop found in beer, the plant still grows
wild across Central Asia. More than 4000 years ago, Chinese farmers
began to grow it for oil and for fiber to make rope, clothing, and paper.
Pinpointing when people began to take advantage of hemp's
psychoactive properties has proved tricky. Archaeologists had
made claims of ritual cannabis burning in Central Asian sites as far
back as 5000 years ago. But new analyses of those plant remains
by other teams suggest that early cannabis strains had low levels of
tetrahydrocannabinol (THC), the plant's most powerful psychoactive
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