3 Questions with a Scientist: On Liking Lichens

Dinosaurs didn’t survive the mass extinction that happened 66 million years ago. But Thorsten Lumbsch wondered what happened to something much smaller that was also around at the time: “I thought, ‘My god, the poor lichens, they must have suffered too, how can we trace what happened to them?’”

And so Lumbsch, Field Museum postdoctoral researcher Jen-Pan Huang, and fellow scientists started using DNA to look back in time and get an idea of what happened to lichens after the asteroid hit. It turns out, certain types of lichens—organisms made up of fungi and plants living together—seized an opportunity to thrive and fill the gaps of plants that died out.

Lumbsch, our curator of lichenized fungi, answered three questions about how lichens survive and thrive, why we should pay attention to them, and how his abiding passion for these unique organisms began at a young age.

In lichens, plants and fungi work together. How does this help them survive?

By living in a close association, lichens are able to survive in habitats where they could not live by themselves, such as a bare rock in the mountains or deserts. They have an astonishing ability to survive dry periods and can be dormant for months. The fungus builds a greenhouse for the algae, which provides the energy for the fungus through photosynthesis. This symbiosis is so tough that they have been shown to survive outer space and also stay alive after having been submerged in liquid nitrogen.

However, they are very sensitive to stress. For example, they cannot tolerate air pollution and this allows us to use them as a canary in the coal mine. Symbiotic systems always are sensitive to stress and react fast—lichens by disappearing from polluted areas, or corals (which also use algae in a symbiosis) by bleaching as a result of climate change.

You first published research when you were 15! How did you fall in love with lichens at a young age?

I was always interested in nature and my parents bought me a microscope when I was 12. However, I started getting interested in lichens at 14 when I found a book on lichens for only one German mark (about 50 cents) in an academic bookshop in Frankfurt, Germany, where I grew up. This started my interest in going out to the forest to try to find these lichens. 

A few years later, I met the author of the book, Aino Henssen, at an open house of a university and she explained that the reason for the cheap price was that her name was misprinted on the book cover—a mistake that helped me get interested in lichens. The professor was so excited that a schoolboy was interested in lichens that she invited me for talks or to work in the collections during my summer vacation. From then on, I continued being interested in lichens and studied with Professor Henssen for my master’s thesis.

We’ve heard of “plant blindness”—is “lichen blindness” a thing, too?

Absolutely, a lot of people tell me they never saw lichens and after learning about them, they see them everywhere. I cannot remember the time I could not see them and always see them wherever I go.

Thorsten Lumbsch, Curator of Lichenized Fungi and Vice President of Science and Education, co-authored research about lichens after the end-Cretaceous mass extinction. Jen-Pan Huang, a former postdoctoral researcher at the Field Museum, is the paper’s first author. Read the paper in Scientific Reports.