Adventures in Cannabis Evolution with Rob Clarke

I’ve interviewed quite a number of people who love cannabis, but Rob Clarke was my first cannabis ethnobotanist. Ethnobotany is an interdisciplinary field that examines the ecology of plants and their cultural, social, and economic significance. Despite the austere-sounding title, Clarke struck me as someone who’s great to have at a party: amiable, genuine, and possessing a great sense of humor. Clarke is currently collaborating with Phylos Bioscience on a project to map the cannabis gene pool. Here’s a condensed portion of our conversation that aired on Cannabis Consciousness News Episode #46.


Q – Talk about cannabis and its relationship with humanity.

A – The influence of cannabis on human culture has been tremendous. Let’s just forget about the drug part of it for minute. It was one of the earliest foods grown in Asia. For Chinese culture, for instance, it was one of the five main grains, as they would call it. It’s not truly a grain but it fills that function. It’s very high in protein, very high in oils, all the things that are lacking in most of the other grains. Rice is very high in protein compared to the rest of the grains, but it’s nothing like hemp seed.

Then hemp fiber, for temperate areas all across from Europe to Japan, was the most important temperate fiber crop for a long time. It was a foundation for those cultures.

India, not so much. If you go to that huge subcontinent, they had lots of fiber alternatives, but as you go into the mountainous areas, it starts to be more restricted environmentally, and seeds become really important as a food crop. In Nepal, for instance, that’s where they triple crop. [Cannabis] has a triple use and effect for their culture. They eat the seeds, usually just parched, and they have it along with beans and rice. That’s basically their mainstay and it adds more protein and oil, especially oil content. They have hemp that they still weave blankets out of, which they walk around in during the daytime and sleep under at night. It’s their standard piece of clothing and domestic textile all rolled into one. And then there’s the charas, the hashish they rub from the plants when they’re rubbing the seeds out. There’s a very low level of smoking that I saw there. They sell the charas and use the rest of the plant.

Q – The 2014 US Farm Bill allows US hemp growing for research purposes. How excited are you about the future of hemp being part of the counterpoint to the planetary crisis we have. Was Jack Herer right, will hemp save the world? Is it our only hope?

Clarke – Hemp will not save the planet, and it’s not our only hope. Hemp has several real drawbacks. It’s really water hungry, it needs a lot of sunlight, and there will be competition with whatever grows well in the area. Any future choices about what to plant should be reliant on where you live.

Q- Tell us about the Phylos BioScience Cannabis Evolution project.

A – The project takes a look at the cannabis genome and how all these different varieties that we have now are related. They’ve already analyzed about fifteen hundred samples so far from dispensaries in about six states. So it’s this big cloud of “who’s your daddy” data. It’s all narrow leaf drug and broadleaf drug hybrids, what people now call Indica/Sativa hybrids but would be better to call Afghanica/Indica hybrids.

When you look at the interrelationships in the genes, it comes out in this big cloud that Mowgli [Holmes, the Chief Scientific Officer at Phylos Bioscience] calls a constellation.  That’s what it looks like too, especially when he rotates it against a dark screen which looks like space. It looks incredible, and within a few months you’ll be able to dive into that, touch on any part of it and flip it so you can center on one variety— maybe your sample that you turned into the project, or a land race like Colombian. You can see how everything after that is related to Colombian or not.

So now we have this cloud that, if you pictured a family tree, would be the canopy.  It would be what happened most recently. So now we’re trying to find the small branches, and the bigger branches below that. The small branches would be early crosses, like a very early hybrid between a Colombian and a Mexican, or a Thai and an Afghan, something like that. That’s very helpful. Then to have the original Thai or Afghan parents is even more helpful, those are fatter branches that are lower on the tree. And if we can go back and get archeological samples from 2,000 years ago and get the DNA out, then we can get closer to the trunk of the tree.

Q- So stepping back a bit, you can take a seed and map its DNA?

A- Yes, we can take a seed, live or dead. It’s more difficult because you have to actually physically excise the embryo from the seed because you need it to represent the plant that would come from that seed, not the mother. It’s easier to sprout a seed, and if seeds are live, then people shouldn’t really be giving them to us, they should be sprouting them. We’ll be really happy to have a couple of the leaves from it, dried leaves are fine.

Q- So you can get the genetics off of a dry leaf?

A- Yes, you can get much cleaner genetics from a freshly-dried leaf than you can from an old dead seed. It’s much easier and much better, cleaner DNA, so you get more sequences and more information from it. So the fresher the better, but old things can be used too. You get more fragmented DNA broken into smaller bits, so you don’t get as many reads of the DNA that contain information. But you do get something so it can all be pieced together through the wonders of statistics.

Q- So what sort of seeds are you looking for, or as you said, leaves from the sprouted seeds, and how can people connect with the project?

A- Well, the easiest way to connect with me is to just email me at There’s also another project that’s allied to this called the Open Cannabis Project.  They have a  website called that is a way to make this information accessible, but also create a forum for people to say what’s what. What’s in a name? The names are often changed to protect the guilty, I say sarcastically. It’s a forum where people can discuss what is the true OG? Where did these things come from? If people are going to develop an interest in heritage, then the people who played the game early on should weigh in and tell us what’s going on. Most of you are still alive.

Emerald contributor since April 2019


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