Q&A with Thor Hanson

Thor Hanson, photo by Kathleen Ballard Photography

Thor Hanson is the author of the new book The Triumph of Seeds: How Grains, Nuts, Kernels, Pulses, and Pips Conquered the Plant Kingdom and Shaped Human History. He also has written Feathers and The Impenetrable Forest, and his work has appeared in a variety of publications, including Audubon and BBC Wildlife. He lives in Washington state.

Q: Why did you decide to write a book about seeds?

A: I’ve had a longtime interest in seeds from a research standpoint; a good portion of my doctoral dissertation was on seeds. I’ve focused in part on the dispersal and genetics of rainforest trees in Central America.

What struck me was, I still didn’t understand how seeds worked! I got really fascinated from a scientific standpoint. It was on my short list of projects to pursue.

I happen to have a little boy who for his own reasons is fascinated by seeds. It’s very much a topic of conversation!

Q: In the book, you ask, “While everyone from gardeners and farmers to the characters in children’s books trust that seeds will grow, what makes it happen?” How does that process actually work?

A: One of the best analogies I came across was from the researcher Carol Baskin—that a seed is a baby plant in a box with its lunch. It encapsulates what’s going on. The parent plant is putting the baby in a box and giving it something to eat. It’s a very useful and charming analogy.

Q: You write, “The dramatic triumph of seeds poses an obvious question: Why are they so successful?” What did you learn that helps answer that question?

A: It really comes down to five critical traits that evolved in seeds. They invented five things that have given them a tremendous advantage in nature.

The first is giving the baby plant some lunch. Spore plants in most cases have no nutrition. [Then,] because the nutrition is there, they put it in a box and defend it with chemicals [or] thorns.

Third, the seed combines parental DNA through pollination. That’s different from spores. Fourth is dormancy. Seeds lie dormant in the soil, waiting for the right moment to grow. Fifth, they evolved to travel in various ways, [such as] a tuft of cottony stuff on a dandelion seed.

If you take the five things together, the seed plant has a great advantage over a spore plant. Spores do still exist.

Q: What are the percentages?

A: It depends which taxonomist you ask. Ninety to 95 percent of terrestrial plants are seed plants.

Q: Given the technologies involved in genetic modification, what do you see looking ahead for seeds?

A: I think there are two main answers. The first is the future of seeds in the world of genetic modification. This is a situation where the genie is out of the bottle and has joined a long line of technology that we struggle to make peace with—nuclear power, drones. How do we put parameters on the use of technology?

The book is not directly about the GMO debate, but about why seeds are so important. It’s certainly a dynamic time in our relationship with them.

I like to look at seeds from an evolutionary standpoint. Seeds are dominant now, but if we were having this conversation 400 million years ago, we’d be talking about how dominant spore plants are.

A wonderful example [of evolution] is orchids. They’re a seed plant form, one of the largest. There are 25-30,000 species of wild orchids.

They’ve become successful using seeds in an unseedlike [way]. They have lost many of the characteristics that make seeds successful…They have come up with a new strategy that’s very successful and relies on symbiotic relationships with fungi.

In the case of orchids, they require no nutrition for seeds because they’re going to get it from the fungus. They don’t need to invest so much in protecting [the seed]. It’s a very interesting look at the evolution of plants.

Q: What particularly surprised you in the course of your research?

A: The surprising thing, coming at it from a scientific perspective—I knew that the story was really interesting. In some ways I was surprised by the depth of the cultural story, how connected we are to seeds.

We care about them because we eat them, but we get more from them—stimulants in our coffee, gas in our gas tanks…You start looking through this lens and you see seeds everywhere. It’s just pervasive.

Q: Your previous book was about feathers. How did the research process compare?

A: There are some similarities. I’m fascinated by objects like feathers and seeds which transcend imaginary but very significant boundaries we erect between the human and the natural world.

From down feathers in a parka to poppy seeds in a cake, we encounter them, but rarely stop and think. These are real touchstones to the natural world.

That is especially important in the modern era, when we more and more are living an urban lifestyle, yet here it is around us every day!

Q: What are you working on now?

A: I am working on a project about bees—native bees as well as honey bees. It’s a wonderful biological story…

--Interview with Deborah Kalb