Fargo, N.D. — Lichens are sometimes called "the most bizarre of all forms of life," because each species is composed of two, sometimes three, separate organisms. One is a fungus, while the other is an alga. Compounding the situation, there sometimes can be a bacterium that photosynthesizes. They are often found in trees and on boulders across North America and around the world.

Ted Esslinger, NDSU professor of botany/biology, previously published a checklist of more than 3,500 species of lichens found in North America. The checklist is updated annually, and now stands at approximately 5,000 species. He also is working with an international group building a database that contains more than 32,000 references dealing with lichens. Esslingeriana idahensis, a genus of lichens, is named in his honor.

"One of the things that make lichens special is they do really well in extreme environments. Some are well adapted to Arctic environments, others to Arizona deserts and still others to Minnesota forests," said Esslinger, who has found more than 100 previously unknown lichen species. "It's an inspiration to discover something no one else knows. That moment of discovery is truly wonderful."

Esslinger is currently collaborating on an effort to study the DNA of a group of lichens. He and his colleagues are hopeful by exploring the genetic makeup they may discover the evolutionary pathway that led to the organism's ability to adapt to diverse habitats.

Esslinger is a past member of the executive council and president of the American Bryological and Lichenological Society. He is a reviewer for many journals, including American Journal of Botany, Bryologist, Environmental and Experimental Botany, New Zealand Journal of Botany and Smithsonian Contributions to Botany.