Meet the Scientist Who Maps the World’s Past and Present Plants

Plant biologist Jun Wen investigates the sprawling diversity of plant life on Earth and the lessons it offers in conservation

Jun Wen sits at a wooden table in front of a bookshelf examining a herbarium booklet of pressed plant specimens.
Wen investigates plants from a variety of families, including specimens preserved in the museum’s collections and those she collects during fieldwork. L. Zhao, Northwest A&F University, Shaanxi, China

Humans love grapes. We eat them by the bunch, ferment them into wine and preserve them as jelly, satisfying a taste for the fruit that research has suggested goes back thousands of years. But combine all the types of grapes that humans use, and you still have only a small subset of the grape family Vitaceae, a group that includes almost 1,000 species. It’s remarkably diverse — counting among its members everything from small succulent trees to wine grapes — and possesses immense ecological and economic importance.

Plant biologist Jun Wen has spent her career studying the diversity and evolutionary history of the grape family, and many other plant groups besides. In the new installment of Meet a SI-entist, we catch up with Wen, a researcher and curator of Vitaceae and Asian plants at the Smithsonian National Museum of Natural History. Wen’s work is featured in the new exhibition, Our Places, which explores personal stories of connection and inspiration from scientists and community leaders. She tells us about her work describing new species, how she untangles the ancient relationships among plants and why understanding plant diversity is crucial for humans and the planet.

You’ve studied a range of different plant groups throughout your career. What drew you to plants and their biology as a research subject?

I became interested in plants when I was a very young kid, maybe five or six years old. I grew up in Hubei Province in central China, and that province is very well-known for medicinal plants. My grandfather was an herbal doctor for my village, so he had a lot of knowledge about plant diversity and how it can benefit humankind as medicine. He went to the mountains to pick plants, and I helped him. So I’ve always had that appreciation for green diversity.

But because I was the daughter of his daughter, I was not allowed to inherit his medicinal knowledge — he’s supposed to pass that knowledge on to his son or to his grandson. But I was guided and fascinated by the plant diversity that I saw every day in the forests. In college, I was studying forestry, and a professor would take us on field trips on the weekends. And in the mountains near my college, there must be 300 species of trees. So I asked him, ‘How come? How can these plants come together in this place so harmoniously?’ And he looked at me and he said, ‘That’s a very good question. You could dedicate your career to studying that question.’ That was the moment. I clearly remember, after 40 years, that minute — that second. I knew I wanted to be a plant biologist.

Wen regularly takes collecting trips, where she gathers specimens like this member of the Vitaceae family, found alongside the Potomac River. H. Dong

What questions guide your research into plant diversity?

One of the questions I focus on a lot actually sounds very simple: it’s to describe the biodiversity that exists in different regions. So I work on describing new species — this week I’m working on describing a new ginseng species from Thailand and have also begun to describe a new grape species from Yunnan Province in southwest China. And then we want to propose ideas of how to classify them, so that we can better communicate among scientists or between scientists and the public.

And then the second major question is how we can use those plants as models to understand the way biodiversity has evolved through space and time. When we look at North American grapes, for example, it’s really interesting that they originated in Central America, and when they reached western North America, they went through a major hybridization event and an ancient hybrid lineage then got established and radiated in vast forest regions of eastern North America. Using grapes as a window, we are seeing the evolution of those forests through millions of years.
Wen often teams up with Alice Tangerini, botanical illustrator at the museum, who creates detailed depictions of the specimens that Wen collects. Above is an illustration of a ginseng species from Thailand that Wen is currently working to describe. Alice Tangerini, Smithsonian Institution

How do you extract information about those ancient plants and their evolution? 

I use different tools. Some of the very fundamental, basic tools are the collections in the museum, as well as greenhouse collections. We use them to see variations and changes from one species to another. I also use our Laboratories of Analytical Biology in the museum, where we do genomic analyses. We used to look at one or two genes as DNA markers, but now we look at hundreds or thousands of genes at the same time. We used to have a post-doc work on one gene for a couple of years, and now we get thousands of them in a month or two.

I feel like such a lucky scientist. Plants hybridize like crazy in the wild. These kinds of processes, without the genomic tools, are impossible to tease apart. Now we actually have very good tools to test our hypotheses, to understand the patterns and the processes of plant evolution and biodiversity assembly.

Along with examining plant DNA, what else do you do in your day-to-day work?

Every day is different. For part of the day, I might document the species in the museum or analyze the vast data we have. I’m also an editor for several scientific journals, working on how scientists communicate with the community. My work is also pretty hands-on. I use the lab a lot, and I do a lot of field work. I feel like each day is so fulfilling, so dynamic.

I think teaching the new generation is also a very important part of our lives as scientists. We do research, and we also train students to carry on the torch. I work with students across the globe, and I like to encourage them to come up with their own questions about biodiversity patterns and processes.

Wen checks out a grape vine with Alicia Talavera, Margarita Salas postdoctoral fellow at the museum. Alice Tangerini, Smithsonian Institution

Why is it important to understand and document past and present plant diversity?

As humans, sometimes we forget — we really rely on plants a lot. Imagine if we didn’t have plants, what life would be like. So doing this science is not just of interest to me as a scientist. We’re trying to understand how humans can benefit from this vast plant diversity. It’s pretty amazing; we think we understand everything about these economically important plant groups, like grapes, but we’re only scratching the surface. With the cutting-edge genomic tools we have, there are a lot of new questions to address: how the species actually interact with each other, how they hybridize and establish in new areas. We’re trying to understand this vast diversity and its potential uses for humankind.

Our science can also teach us to conserve that plant diversity, so it can benefit not only us, but future generations. Humans are causing so much irresponsible change, and many species are in danger. For example, some ginseng species are endemic to such small areas, and I was collecting them 30 years ago, but now I can no longer find them in the wild. Before we even understood them, they went extinct. So extinction is not a fantasy, it’s the reality.

Our whole motivation is that history is a window that allows us to predict the future, and we learn lessons from the past. I think right now our mission is to help people understand how vulnerable this diversity is, and how easily species can go extinct. And we as scientists dedicate our careers to understanding that diversity, to learn how humans can conserve it and make sure our future is sustainable.

This interview has been edited for length and clarity.

Meet a SI-entist: The Smithsonian is so much more than its world-renowned exhibits and artifacts. It is a hub of scientific exploration for hundreds of researchers from around the world. Once a month, we’ll introduce you to a Smithsonian Institution scientist (or SI-entist) and the fascinating work they do behind the scenes at the National Museum of Natural History.

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