What are vascular plants?
When you look out your window or look at a picture of Earth from space and see the color green, what you see are vascular plants. They create the habitats that other organisms use for food and shelter. Vascular plants include the groups called lycophytes, ferns, gymnosperms (conifers and related plants), and angiosperms (or flowering plants).
They are called vascular plants because they have specialized cells called tracheids, in a tissue called xylem, that transports water and minerals throughout the plant body. These cells are also structurally strong and enable plants to grow to some height. Vascular plants also have a tissue called phloem that transports the sugars produced by photosynthesis.
I tell students that, in a way, the vascular tissues in plants are doing the job of both the circulatory system and the skeletal system in animals. Non-vascular plants, such as mosses, lack vascular tissues and are thus not able to grow very tall. The appearance of vascular plants on earth approximately 420 million years ago set the stage to drastically change the world. Before that there were no forests as we now know them.
What sparked your interest in studying plant diversity, and specifically that of the eastern U.S.?
I grew up in Ohio and Michigan, and became interested in plants because I spent a lot of time outside exploring. I loved being in forests and prairies. When I went to college, I had amazing teachers who inspired me to learn more about plant diversity. In particular, Gary Hannan at Eastern Michigan University, and Burt Barnes and Melaine Gunn at the University of Michigan who taught the famous Woody Plants class. From there, I expanded my interest to all the plants of the world, including tropical areas that have a much greater diversity of species than we have in the eastern U.S.
Tell us about riverweeds.
Riverweeds are a fascinating, and a somewhat oddball, family of aquatic plants that I started studying during my Ph.D., and have continued working on since then. They are the largest strictly aquatic flowering plant family in terms of the number of species. Plants in this group live where almost no other flowering plants live, directly attached to rocks in the swift, flowing currents of rivers and waterfalls. They create crucial habitats that provide food and shelter for fish and invertebrates.
We have one species of riverweed in the rivers of the eastern United States, but most of the diversity is in the tropical regions of the world such as South America, Africa, and Southeast Asia.
I’ve been lucky to go on several trips to document these species, and on nearly every trip, we discover species new to science. By increasing our understanding of riverweeds, we can better protect rivers and other species that occur in the same habitats.
Unfortunately, riverweeds are under threat from the construction of hydroelectric dams in rivers. These dams make it so that the plants can no longer survive in the river. To protect the plants, we must know what species exist and where they grow. That is where I hope to help in terms of the conservation of the world's biodiversity.
What's going on in the collection right now?
Lots! We have many faculty, staff, and students from EEB and beyond using the collection for exciting research. In terms of the work that I do, I am focusing on three things lately. First, I am leading a digitization project funded by the National Science Foundation that focuses on the plants from Asia in our collection, the All Asia project. This grant allows us to train students in herbarium specimen digitization which includes taking pictures of specimens and entering their data in our database. We share this data with the world through various websites such as the Consortium of Midwest Herbaria.
Second, I am working on curating our collection of riverweeds. We have the best collection of this family in the world, and there is a lot we can do with it in terms of biodiversity research and the discovery of new species.
Finally, I help Tony Reznicek with the Michigan Flora Project. This project is invaluable to the public, students, and researchers, as well as state agencies, such as the Michigan Natural Features Inventory, that help to conserve Michigan’s biodiversity. Anyone interested in the plants of Michigan should be aware of this awesome resource.
Do you have a favorite specimen within the collection?
That is a tough question to answer. It’s like asking a parent to name their favorite child! If I had to choose, it would be one of the riverweed species that I helped collect from the Roosevelt River, in Brazil. It was just such a beautiful place, and we were told there were jaguars nearby, so we had to be careful!
Who or what is inspiring you within the world of science right now?
Two things come to mind. First, anyone who is out exploring the natural world to discover and describe new species is very inspiring to me. To be successful in that activity, you must know a lot about the group of organisms you are studying and the environments in which they occur. These days, as scientists spend more time at a computer or in a lab, there is something special about discovering things in the natural world. There are so many new species to be discovered, and much of our understanding of higher-level questions in the field of ecology and evolution rely on a basic understanding of what species exist and their geographical distributions.
The other inspiring item is the sheer amount of data that we have available to address pressing research questions. Not too long ago, we just didn’t have enough data to answer some questions, be it molecular data, images of specimens, etc. Or it just took a very long time and a lot of money to acquire the data needed. Now, it’s almost the reverse problem. We have so much data, and it’s much cheaper and easier to obtain, that sometimes it is hard to analyze it properly because there is so much available. People working on these problems and the things they can do with this flood of data are quite inspiring. But when it comes down to it, we don’t want to lose sight of exploring, describing, and protecting the natural world.
