Epilogue: What Do I Do?

To be a scientist is to know that most of what is knowable is not yet known. This is the thrill of it all, the great potential for discovery—and it’s why I keep going back to work. But to be human is also to be frustrated by our ignorance, especially in those moments in which we need to make decisions. With food, we make decisions every day. We need to figure out ways we can through those decisions, make our food systems more sustainable, more just, and less prone to the total failure of crops, and countries. We need to figure this out even before we understand everything (we will never understand everything).

There are some simple things you can do. You can waste less of your food. You can eat less meat. This entire book has been about plants, but eating meat is contingent on the plants being there in the first place to feed to the animals. With some unusual exceptions (such as when chickens are sustained on fodder that would otherwise be waste, including rotting feathers and corn stalks), meat eating is nearly always a waste of food resources relative to eating plants. You can eat local. You can choose foods produced using heritage seeds and produced in agricultural systems managed ecologically. This is particularly important if you live in a region near one of Vavilov’s centers of crop diversity. You can also have fewer kids and, if you are in a country with a food surplus, welcome those refugees from countries in which food systems have collapsed.

All of these actions can help. But the solutions these life changes favor just reduce the urgency of our race against pests and pathogens. The race does not stop. What else can you do? As I’ve already noted, if you have a farm, you can help scientists in this race by working with your university extension agent or with PlantVillage to document the pests and, especially, pathogens threatening our crops. But what if you don’t have a farm, or even, really, room for a garden? Such is my case. I have a tiny yard with barely enough room left for one more potted plant. In part this is because the yard just isn’t very big. In part it is because when writing The Wild Life of Our Bodies, I became fascinated with the idea that we could transform cities into places in which fruit trees could help to produce large quantities of food. Somewhat to the chagrin of my neighbors, I ripped up much of my grass and planted peach trees, apple trees, two kinds of fig trees, an olive tree, mulberry trees, a variety of dogwood with edible fruits, a plum tree, cherry trees, and a pomegranate tree. I can start to document the pathogens and pests on these trees for PlantVillage. I will. But when I was talking about all of this in my research group another idea bubbled up, an idea having to do with squash plants, be they pumpkins, acorn squash, bottle gourds, cucumbers, or one of the other plants of the squash family (Cucurbitaceae).

My research group is full of wonderful people in various stages of their careers. Eddy Cruz, for example, is an undergraduate student studying the evolution of the warrens of mammals. Zack Varin, another undergraduate student, is studying the biology of salt. Michelle Musante is studying Delftia bacteria that precipitate gold out of solution (really). Megan Thoemmes, a graduate student, studies the species that live in human houses and the nests of chimpanzees. I’m looking for a new student, on a joint project with Ben Reading, to study the biology of caviar. In addition, the group has many postdoctoral researchers. The postdoctoral researchers have all completed their degrees (typically at some other institution) and are in my lab for a few more years of research before they move on to faculty positions or other sorts of jobs. Great ideas can come from anywhere in the research group, and many of the best we have ever had came from the undergraduate students, but this particular idea, the one having to do with squash, bubbled out of the minds of the postdocs.

It is hard to say exactly when the idea arose (it always is), but I can trace a few elements of its origin. It started with dandelions. One of the postdocs in my group, Julia Stevens,1 was working with teachers and middle school students to try to figure out whether the success of dandelions in extreme environments is possible, in part, because of the unique microbes on their roots (it appears it might be). Julia’s work got the whole research group thinking about the beneficial microbes that live on plant roots. Another postdoc, Margarita Lopez-Uribe, meanwhile, was working on squash bees.² Much of the squash you have eaten in your life is the fruit of a plant pollinated by a squash bee.³ Yet we don’t even know very much about where squash bees live or why. The species Margarita studies, for example, seems to be absent from Florida, but it may simply be that no one has looked for them there very well. At some point the conversations about squash bees, squash plants, root microbes, and dandelions began to bleed into each other. We began to wonder how much was known about the beneficial root microbes of squash. We began to wonder how much was known about the associates of squash in general.

Then, just as we were talking about how little is known about the associates of squash, Margarita met another postdoctoral researcher, Lori Shapiro. Lori was working at Harvard University and was studying a species of beetle, the striped cucumber beetle, that has evolved the ability to deal with the toxins (cucurbitacins) in the leaves, roots, fruits, and flowers of squash plants and, in doing so, to eat squash. This beetle is a problem in and of itself, but it also carries a pathogen of squash, Erwinia tracheiphila.⁴ The beetle is found throughout North America and Mexico, but the pathogen is currently found only in the northern United States. If the pathogen spreads it could pose a major threat to squash (including pumpkins, Cucurbita pepo—this could be the pathogen that ruins Halloween!). Little though is understood about what limits the spread of this pathogen, or even where it lives, similar to the case of the squash bee. Thanks then to conversations with Julia, Margarita, and Lori, the natural history of squash was very much on my mind. Then came the bottle gourd.

In the spring of 2016, my then six-year-old son appeared to have planted seeds in our backyard in Raleigh, North Carolina. Where the seeds came from, we aren’t sure. In any case, some seeds fell, and among the places they fell was between the gravel stones behind our air conditioner, in the one place of dirt we own in which the sun is not blocked out by fruit trees. We were in Denmark for the summer and so none of those seeds were tended to. Yet, amazingly, one of the seeds grew. A single seed. It was a seed of the bottle gourd plant (Lageneria siceraria), another member of the squash family. Unlike pumpkins and some other kinds of squash, bottle gourds were domesticated in Africa, yet their biology seems, superficially, similar to that of other squash plants. They grow as vines. They produce large fruits. They evolved to be dispersed (eaten in one place and deposited in feces in another) by megafauna, be they elephants or giant sloths.5 They grow quickly. When we got back to the house that single gourd plant was thirty feet long and had dozens of flowers. It seemed to threaten to spread over the fence and out into the road (and then it did spread over the fence and out into the road). My son proceeded to watch those flowers every day, to tend to his plant, to note which leaves were being eaten, and to otherwise study it. Having spent time reading Margarita’s papers and talking about bees, I naively told him to watch for squash bees. He reported back that he hadn’t seen any bees, only moths. This, I thought, must be wrong. But, our collective ignorance of squash in mind, I checked published studies and saw that where they are native, bottle gourds are indeed pollinated by moths.⁶ No one appears to have studied bottle gourd pollination in North Carolina. My son’s record was a new data point (or it would have been had he taken a picture). It was also the germ of an idea. What if we could get people across the United States (and maybe around the world) to plant key crop species in their yards, but also, in having done so, to begin to help document their associations with pathogens, pests, mutualists, and all the rest?

The good news is that we, in my lab group, knew exactly what to do. We already run a program, Students Discover, through which teachers can work with students to do real science as part of citizen science projects. Such efforts—in which we engage the public, particularly kids, in doing real science—are our bread and butter. We have run projects on belly button biodiversity, the microbiology of homes, ants in schoolyards, and the mammals in backyards. We could, we thought, do a project on squash. In fact, it has already begun. We have begun sending squash seeds across the United States. We send those seeds with guides to planting them, but also with links to online data forms in which observations on pathogens, pests, and mutualists, including pollinators, can be recorded. In some cases, specimens can be sent back to us (for example, if a striped cucumber beetle is found). In other cases, a picture will suffice. We have developed lesson plans that link these planted squash to curriculum goals in the classroom. We have worked with chefs to develop recipes to cook and use what is grown. We have started with one variety of squash, but as the project spreads we will introduce other varieties. (My son, who helped inspire this effort, is planning to plant squash next year, but he will also plant another gourd. As for the gourds he grew this year, they are drying. He wants to make banjos, one for him, others for his friends.)

Our initial goal is to monitor squash plants in every state. You can help us plant squash and, in doing so, keep ahead in the one race that really matters. Our long-term goal, if this all works, is to consider other crops too. Chilies, for example, or cabbage. One of the most exciting things about science is being able to bring people together to answer a mystery in which they have a shared interest. For our squash project, we have all of the experts necessary to help figure out what each of you see on your squash plants and what it means. Margarita Lopez-Uribe, now a faculty member at Pennsylvania State University, will be helping with the study of the squash bees and other pollinators. Julie Urban, also a faculty member at Penn State, will be focusing on the plant-sucking kin of the mealybug that might be found on the plants. Lori Shapiro at Harvard will be keeping an eye on the beetles observed on the plants and the Erwinia microbes they carry as well as guiding the overall project. Through PlantVillage, David Hughes and Marcel Salathé will be our partners to consider other pathogens. Angelica Cibrian Jaramillo at Langebio in Mexico will continue the same work in Mexico, where many more species of squash bees (and probably herbivorous beetles) can be found.

Then there is you. You will be the one watching, taking pictures, taking notes, and in some cases collecting samples. You will be part of our attempt to democratize the study of the crops on which all of civilization depends. What we are trying to do is, in our small way, to reinvigorate the land grant system in a model in which the university is connecting not just to farmers, who are now so few, but to anybody with a patch of land. The additional hope, along the way, is to reconnect kids with growing their food, with the biology of food, and in as much as so many kids in the United States still suffer hunger, with food itself.

Watching squash may not seem very radical. After all, our squash project is the logical extension of efforts to make scientific process ever more transparent, accessible, and participatory. Much of the data on which our knowledge of the effects of climate change on birds and plants, for example, are based on projects in which the public actively participates. Yet, engaging the public to help study crop plants, and then making all of the resulting data freely available, stands in stark contrast to the modern agricultural status quo, the status quo of science done by or for agroindustrial companies. The work done in such companies is largely secret. The knowledge such work produces accumulates, but not publicly. Inside each of these companies then is a kind of private knowledge that is growing in size. Just how much of our global knowledge is private is hard to say. More, I’ll speculate, than has been the case at any moment in the last hundred years. In this light, the democratization of the study of squash (and then other plants) is indeed something very different. Relative to the dominant trajectory of agriculture, planting and studying seeds yourself is an active step in a different direction. It is a revolutionary step in as much as it will yield new discoveries publicly, but, perhaps even more important, because it has the potential to reconnect our children (and all of us) to the reality that we are connected to our crops and our crops are connected to wild nature, or need to be anyway. Moths came to my son’s gourd flowers and pollinated them. It is likely that in some places where children or adults plant squash as part of our project no pollinators will arrive, no squash bees and no honeybees either. When this happens, it will offer us new insight into the biology of squash, but it will also beg the question of where the squash bees might have gone and what you can do to restore them. It will beg the question of how in each small place we can cultivate not just crops, but also the thousands and thousands of other species on which we all depend.

If you plant a squash, you might make a discovery. When and if you do make a discovery, it will be public (and published) that it might be built upon by someone else growing a single squash, or by farmers or scientists anywhere else in the world. By that time, with any luck, you will be sitting down to eat your squash. When you do eat what you grew, think of everything you are connected to, including the farmers and scientists who saved the seeds and have kept the pests at bay, but also the wild species such as the squash bees, and as of yet unstudied root microbes, whose consequences flavor your daily meal. Wherever you live, whatever you eat, you are linked to the rest of life through what you consume, the wilderness that each bite threatens and yet, at the same time, depends upon.