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Science of cannabis: #1 A long history and a seismic shift

Season 1, Ep. 1

Cannabis is having a moment. Half of the US population lives in a state where marijuana is legal, and 9 in 10 people nationwide support legalisation in some form. This is a stark difference from mere decades ago, when prohibition was the norm in the entire US. Meanwhile, if you live in Malta, Uruguay, Canada – and maybe soon, Germany – your entire country is one with legal recreational pot. And access to medical marijuana extends to even more countries, including the UK and Australia.

But as medical and recreational use become more popular and increasingly accessible, how exactly did we get to this moment of change? What has research been able to tell us – so far – about how the plant produces its euphoric effects, what medical purposes it may be able to serve or how it might be harmful? And how could our relationship with this unassuming leaf change in the coming decades?

In the first of this three-part special series on the science of cannabis, Christie Taylor explores our deep history with cannabis, from the first domestication 12,000 years ago in Northwest China, to the current skyrocketing popularity in the United States and around the world.

Learn more: The team at New Scientist investigates cannabis and the brain, the environmental cost of growing cannabis, and other questions in this special reporting series. Visit

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