“Jeff Bezos, Elon Musk: these incredibly wealthy people are making their money off the backs of people, and resources which they are exploiting from the earth. They need to pony up and pay for this,” the world-renowned professor of forest ecology, Suzanne Simard, told me at an outdoor café in St James Park, London. “[They] undermined our government so that they could make cheap s**t. We have to close the circle of responsibility […], we have to hold them to account.” With her wispy silver hair, piercing birdlike eyes and simple black coat, Simard in many ways conforms to the image of an academic being shepherded around the city on a book tour. But as these passionate outbursts suggest, little about Simard is typical. Simard’s research has transformed Western understanding of forests, and was the basis for the “tree souls” in James Cameron’s blockbuster movie Avatar.