Interview with John Kress, Distinguished Scientist, Smithsonian Institution

Dr. W. John Kress is Distinguished Scientist and Curator Emeritus at the Smithsonian’s National Museum of Natural History. He was Curator of Botany for over thirty years and formerly served as the Interim Under Secretary for Science at the Smithsonian and Director of Science in the Grand Challenges Consortia. Dr. Kress received his education at Harvard University (BA, 1975) and Duke University (PhD, 1981) where he studied tropical biology, ethnobotany, evolution, and ecology. He is a taxonomic specialist on the tropical Zingiberales and his current research is focused on biodiversity genomics, conservation, and the Anthropocene. Among his over 200 scientific and popular papers are his books Plant Conservation: A Natural History Approach, The Weeping Goldsmith, The Art of Plant Evolution, and The Ornaments of Life: Coevolution and Conservation in the Tropics. His most recent book on climate change and society is Living in the Anthropocene: Earth in the Age of Humans. He is a Fellow of the American Association for the Advancement of Science and is currently Visiting Scholar at Dartmouth College and the Arnold Arboretum of Harvard University. He lives in Dorset, Vermont.

Tell us about your work with Heliconia and the plant discovery that you named after Margaret Mee.

I have studied the tropical plant Heliconia for over forty years. As a taxonomist, one often devotes an entire career to a certain group of plants, preferably one that is not very well known and needs some concerted scientific work. Heliconias are big, fleshy, and difficult to collect and so they were relatively unknown when I started out working with them as a graduate student. After spending many years in South America searching for new species of Heliconia, I was in my office at the Smithsonian thumbing through Margaret Mee’s book Flowers of the Amazon and saw her painting of a type of heliconia near the border between Venezuela and Brazil that I did not know. The flowers of heliconias tend to be brightly colored to attract hummingbirds that pollinate them, but the heliconia in Mee’s painting had a greenish-yellow color and it looked quite different from those I knew. Anyway, when I saw the plant in her painting I thought: “I have to find it, I don’t know what it is.” I knew I was going to name it after Margaret Mee.

Several years later, when I was in Venezuela collecting plants, I decided to find this Heliconia so I organized an expedition up the Orinoco River to where it meets the Vaupés River. With two other botanists (one from Venezuela named Ernesto Foldats and the other a student from Germany) along with my research assistant Cheryl Roesel, I flew down to a missionary group working with the Yanomamö indigenous people where we knew there was a little air strip near Platanal along the Orinoco. Once we landed and paid our respect to our hosts in the region, I headed into the forest along the river. It took me about five minutes to find the new Heliconia! You can tell how excited we were from the photograph (fig. 14). We made some botanical specimens for the local herbarium in Venezuela and the Smithsonian. I took copious notes and measurements. Later I decided that the plant was not a unique species so I named it as a variety and called it Heliconia chartacea var. meeana. (Alice Tangerini’s botanical illustration for the new variety’s scientific publication is on display in the exhibition.) We flew back that afternoon after a brief celebration. It was a one-day expedition and finding the plant was not that difficult. The return was another story. We had to fly out on a tiny little plane while it was still light. After takeoff I was sitting next to the pilot when the engine stopped while we were high over the rain forest. I thought: “Hey, I have finally found Margaret Mee’s Heliconia and the engine has stopped. What is happening?” Then the pilot looked over at me and commented “Oh, I forgot to switch the gas tanks.” He flipped the switch and we continued on our way.

Fig. 14. Photograph of John Kress (center) and team with the newly-found Heliconia.

When we were exploring the ecological themes of the exhibition, you suggested that we include the two etchings by Bryan Poole. Why?

One reason I focused on heliconias as a scientist is that I am interested in plant-animal interactions and these plants have evolved highly specialized relationships with their pollinators, primarily hummingbirds. Heliconias are mostly found in the neotropics from central Mexico down to northern Argentina, including the Caribbean. About 200 species are native to this geographical region. They all have brightly colored flowers and bracts that open during the day to attract their hummingbird pollinators. Another strange group of heliconias in the South Pacific is found from Samoa to New Guinea and they are completely different: they are a dull, green color and flower at night. They are pollinated by bats, which can’t detect color and forage after dark, so the Pacific heliconias have lost their bright colors. This is evolution at work.

I have also been studying the interactions between heliconias and hummingbirds in the eastern arc of the Caribbean islands for a number of years. The two species of heliconias native to these islands and the one species of hummingbird have coevolved in a very unique and interesting way. The two heliconias are quite different from each other but the single hummingbird that pollinates them is so specialized that the females visit one species of heliconia and the males visit the other species. In other words, one sex of the hummingbird has evolved with one species of heliconia and the other sex has evolved with the second species of the plant. Evolution is fantastic. This system was so unique and exciting that I convinced the artist Bryan Poole from London to create etchings of the two plant species and the two sexes of hummingbird that pollinate them. We worked together in the field on the island of Dominica and eventually he completed these two etchings, which show the plants interacting with their hummingbirds in their natural environments. Plants do not exist in isolation as they are often depicted in the portraits painted by artists and the images shot by photographers. Rather, they inhabit rich and diverse habitats populated by many plants, numerous birds, other animals, and microorganisms. Today, many of the highly specialized interactions among these creatures are severely under threat of extinction (figs. 15–16).

What changes have you seen in the Amazon’s ecosystems since the beginning of your career?

The Amazon region of South America is one of most complex natural environments on Earth hosting millions of species of plants and animals. I have traveled to parts of the Amazon in Colombia, Venezuela, Ecuador, Brazil, French Guiana, and Guyana searching for heliconias and studying their interactions with animals in the forests they inhabit. Like Margaret Mee, who traveled up the rivers and tributaries of the Amazon of Brazil painting the many known and unknown plants she encountered, I have watched many of these habitats change radically as human populations migrated into previously untouched forested areas. Mee usually represented the plants she painted on a simple white background. But towards the end of her career, as she became more and more concerned with forest degradation and destruction in the Amazon, she began to place the focal plant or flower into the natural background where it may be found in nature. The portrait of the Philodendron in this exhibit is one of these later paintings and shows the plant surrounded by native trees and vines. Dr. Shirley Sherwood, who provided this painting for the exhibit, believes that Mee added the background after the fact in order to emphasize the richness of the Amazonian forests and the impending threats to the wonderful plants and habitats she knew so well. The recent unprecedented fires raging across the Amazon of Brazil are only the latest chapter in the ever-increasing impact of humans on these environments.