UW News

November 12, 2015

From garden to gut: New book from UW’s David Montgomery explores an unfolding scientific revolution

UW News

A new book by University of Washington geologist David Montgomery weaves history, science and personal challenges into an exploration of humanity’s tangled relationship with microbes, perhaps the least loved and most misunderstood creatures on Earth — and in you.

The Hidden Half coverThe Hidden Half of Nature: The Microbial Roots of Life and Health” comes out Nov. 16 from W.W. Norton & Co. Montgomery, a UW professor of Earth and space sciences, co-wrote the book with his wife, Anne Biklé, a biologist and environmental planner. From restoring the soil in their urban yard to building a garden, to grappling with a cancer diagnosis for Biklé, the authors share their discoveries about the unfolding revolution of microbiome science and how it transformed their view of nature — and themselves.

The book recounts the heyday of microbiology that led to germ theory and how, by the late 20th century, scientists changed the tree of life to reflect the dominance of microbial life. It then focuses on the new understanding of microbes now emerging from seemingly unrelated fields such as plant science and immunology. Drawing on this latest work, the authors see stunning similarities between the root of a plant and the human gut that are both profound and fundamental. Beneficial relationships between microbes and their human and plant hosts are unimaginably old and have shaped each through the millennia in ways we are only beginning to understand. The book covers unusually effective new therapeutic approaches based on microbiome science, including fecal transplants for people and probiotics for soils.

Montgomery and Biklé urge cultivating and protecting the microbial allies deep within our gut and beneath our feet to restore the land and heal ourselves. They see a common pathway for doing both — mulching our inner soil with a diet abundant in plant foods and mulching the soils beneath farms and gardens with organic matter and cover crops.

Montgomery is a three-time winner of the Washington State Book Award, for “The Rocks Don’t Lie: A Geologist Investigates Noah’s Flood” in 2013, “Dirt: The Erosion of Civilizations” in 2008 and “King of Fish: The Thousand-Year Run of Salmon” in 2004.

Montgomery and Biklé, who will be speaking at Town Hall, Wednesday, Nov. 18, answered questions about their book for UW Today:

Q: The book is part history lesson, part science book, part a personal narrative. Where did the idea for the book originate? Did the concept change over time?

big rock and maples

The book describes the surprisingly fast restoration of soil in an urban Seattle yard.Anne Biklé

A: The book began in the garden, and we remain astonished at where we ended up. Our original intent was to write a hybrid memoir-essay about building our garden, and the need to restore soil globally. One of the first areas we began to research was the effects of adding organic matter to soil, since that was what we had done. Once we dug in, we began to realize that microbes play a foundational role in soil fertility and plant health.

Then the human health dimensions of the microbial world hit us hard in 2011. We were partway through writing the book when Anne was diagnosed with a virus-caused cancer. She has since made a full recovery, but the microbial world was suddenly not so wonderful. While we’d always planned to research and write about food and human health through the lens of soil health, we never imagined that a cancer diagnosis would help us frame the topic.

And as we began putting the story together it was amazing to read things in gastroenterology and immunology journals that were the same concepts we’d encountered in plant science and agronomy journals. At this point, we knew we were onto something bigger, about how important the hidden half of nature is to the health of plants and people.

Q: You wrote the text together, your first time collaborating on a book. What was that like?

David Montgomery and Anne Biklé

David Montgomery and Anne Biklé

A: We get asked this question a lot. As in any endeavor, there are parts that go so well it barely feels like work, and there are parts where you struggle. But the truth is, neither one of us could have written the book without the other. And we think the book is far better because of our collaboration and different expertise. Obviously we know each other very well and our strengths and weaknesses as writers. Most of the time our thinking converged. But we had heated disagreements, too. Early on, however, we adopted a simple rule — we both had to be satisfied, at least minimally, with both the substance and style of the writing that would become part of the final manuscript.

Q: What is the coolest thing you want people to know about microbes?

A: Microbes are integral parts of every organism on this planet. Yet we’ve spent the last century trying to scrub them off our bodies or indiscriminately kill them. So it is quite astounding to now learn that communities of microbes play as significant a role in preventing disease and sickness as in causing them. And the mechanisms that underlie this reality reveal something just as cool: Microbes considerably expand the number of genes within us. There are around 25,000 protein-coding genes that we each inherited from our parents. The bacterial members of our microbiome contribute approximately 2 million more genes. Add approximately 4 million additional genes from the rest or our microbiome — like viruses — and that’s pushing 6 million genes working away in us that we didn’t inherit in the usual fashion.

This is a pretty fundamental insight. It calls into question many common practices in medicine and agriculture — and is guiding the way to new practices that can address some of the most critical problems facing humanity today, from flagging soil fertility to the rising incidence of chronic and autoimmune diseases around the world.

Q: Dave, your previous books have been about large-scale things, like erosion and floods. Does this book reflect a change in your focus as a geologist?

painted wheelbarrow

The book features Biklé’s wheelbarrow with racing flames, used to add organic matter to feed soil microbes.Anne Biklé

A: I haven’t so much changed my focus as a geologist, but more how I see nature and the soil. Still, I’m not about to try and retool myself into a microbiome researcher. I’m just not that good at or fond of lab work — I became a geologist because I like to be outside. This book greatly enhanced my awareness about the connections between soil fertility and the microbes that mediate those processes. It really opened my eyes to how fast soil carbon and fertility can be restored if one focuses on the health of soil microbes. And that has completely changed how I think about the potential to keep humanity’s relationship to the soil from following the historical pattern of soil degradation that I laid out in my previous book, “Dirt: The Erosion of Civilizations.” In fact, I’m now working on a book for which I’ve been interviewing farmers around the world who have restored depleted soils, and in the process slashed their agrochemical use without any loss in crop yields. “The Hidden Half of Nature” naturally flows into this next book because the soil restoration techniques of these farmers, by and large, involve better stewardship of the soil microbiome.

Q: Do you think this book is part of a broader shift in how people think about and interact with microbes?

A: Given all the discoveries about microbiomes — that seem to grow daily — we certainly think so. It really is time to change our relationship with the microbial world. It’s already begun at some level, if you consider the surge in interest in fermented foods like sauerkraut and yogurt. An unusual medical therapy based on microbiome science — fecal transplants — is more evidence that a shift is underway. And in agriculture, farmers are starting to see the benefits of inoculating their soil with beneficial microbes or growing them in the soil through planting cover crops. We see this shift as part of something much bigger, and try to capture it in the last chapter of the book when we write: “Nature is not out there in some distant and faraway land. She is closer than we ever imagined, right inside of us.”


For more information, contact Montgomery at 206-685-2560, 206-618-9220 or bigdirt@uw.edu.