How did collards get to remote oases on the edge of the Sahara? That’s what ethnobotanists Bronwen Powell and Abderrahim Ouarghidi have been looking into for like 20 years now, and it’s a fascinating story. Which you can read about in detail in their paper in Economic Botany. They also present an abbreviated form of the argument in The Conversation. Which got Nibbled some months back. But actually what I recommend you do is listen to Jeremy interview the intrepid duo in the latest episode of Eat This Podcast.