At Southern Arkansas University, learning often happens outside of the classroom, and sometimes it happens around the world.
SAU honors student Majesta Miles and Dr. Shawn Krosnick, assistant professor of biology, traveled along the southeastern coast of Australia for five weeks from June 24 – July 31, 2011. They had one goal: to determine what kinds of birds were pollinating the Australian species of passionflower.
Krosnick, as part of a collaborative research grant awarded by the National Science Foundation, has been studying the evolutionary relationships among more than 250 species of passionflowers (scientific name: Passiflora) for the past four years.
As part of this research, she and her collaborators have discovered that the Australian species are very special: while the Australian species look nearly identical to flowers in the Caribbean that are visited by hummingbirds, their DNA sequences show that they are only distantly related. In fact, they are more closely related species of Passiflora from China and Southeast Asia. Moreover, hummingbirds are only found in North and South America, so they couldn’t be responsible for pollination in Australia. So what could explain the remarkable similarity between the flowers of the Australian natives and the Caribbean species?
To solve that problem, they needed to know what pollinators visit the Australian Passiflora. While the flowers are quite beautiful and widely cultivated, no one had ever documented their floral visitors. Speculations abounded, but there was no hard evidence. This prevented them from making accurate comparisons between the hummingbird-pollinated species and the Australian species.
To make the much-needed field research possible, Krosnick was awarded $7,000 in supplemental funding from the National Science Foundation to offer a Research Experience for Undergraduates (REU) that would allow her to bring an SAU student with her to Australia.
Through a competitive application process, Majesta Miles was chosen to accompany Krosnick with the field research. As part of her commitment to the project, Miles would give a poster presentation on bird pollination syndromes in Passiflora at the International Botanical Congress meetings in Melbourne, Australia. Miles was also awarded $1,200 from SAU Grants for Undergraduate Research that paid for her student registration for the Congress.
On June 24, Krosnick and Miles headed to Brisbane, Australia to begin their field work. They were hoping to find Passiflora herbertiana, one of the three native species of Passiflora in Australia. Based on a tip from a local botanist, Krosnick and Miles decided to investigate Mt. Tamborine National Park, a protected area in southeast Queensland near the border with New South Wales. They were lucky enough to locate a huge population of Passiflora herbertiana along the edge of the rainforest. They camped out for ten days using both still photography and video to capture animal visits to the flowers.
They also collected nectar samples from the flowers each day and recorded all types of data including the length of time the flowers were open, the amount of nectar they produced, and any insects observed on or near the plants.
Finally, on the third day of field observation, they got extremely lucky. Suddenly, a brown bird shot out of the forest and began to hop about within the flowers. They couldn’t believe their eyes and almost missed the shot. Fortunately for them, this bird made several more visits to Passiflora herbertiana over the next week. They identified the bird as a Lewin’s Honeyeater, a passerine bird that specializes on floral nectar. Over the week, two additional species of birds visited the flowers: the Eastern Spinebill and the Noisy Miner.
By the end of their trip, Krosnick and Miles had traveled more than 1000 miles from start to finish over five weeks. They visited five National Parks and met 12 local botanists, ecologists, and conservationists. They had collected a tremendous amount of data, including direct pollinator observations, floral nectar samples, and pollination compatibility analyses.
Miles had the opportunity to present her work on pollination syndromes in Passiflora at the world’s preeminent botanical meetings in Melbourne, Australia.
“The research experience I gained in Australia was above and beyond anything I had expected,” Miles said. “With four weeks of extensive field work dealing with Passiflora, I had the chance to explore and learn about botany in a hands-on way I never could have experienced in the classroom.”
Krosnick is now working on processing the data she and Miles collected in Australia, which has created several new research opportunities for other SAU undergraduates. For example, the nectar collections performed by Miles have resulted in a new collaboration between Krosnick and Dr. Tim Schroeder, assistant professor of chemistry and director of the Natural Resource Research Center. They are working with honors student Samson King to analyze the sugar components of floral nectar in P. herbertiana to better understand pollinator preferences in this species.
