Biology professor Chris Smith awarded NSF CAREER grant

by University Communications,

Assistant biology professor Chris Smith has been awarded an $850,000 National Science Foundation CAREER grant to support his research studying Joshua trees and yucca moths.

The Early Career Development (CAREER) award is NSF’s most prestigious award. The grant is given in recognition of junior faculty members who achieve excellence as teachers and scholars through outstanding teaching and research, and by integrating education and scholarship.

Smith is the first faculty member at Willamette to receive a CAREER award.

“When I got the call, the first thing I did was run screaming through the hallways. Then I told my technician and called my parents and my post-doctoral advisor,” Smith says. “It feels like a big sense of relief. I finally got some national recognition that the work I’m doing is good.”

With the grant, Smith will spend the next five years working with Willamette University students, a post-doctoral scientist and members of the public, studying what he suspects to be the coevolution of yucca moths and yucca trees.

Are yuccas and their pollinators coevolving?

Coevolution is a process of mutual adaptation in which two species evolve in response to one another. For example, over time cheetahs may have evolved to become faster, and thus better able to capture gazelles, while gazelles may evolve to run still faster, and keep away from the cheetahs.

This process of reciprocal evolutionary change is thought to be widespread in nature, and may be important in areas as wide-ranging as managing agricultural pests to understanding diseases like the flu and HIV. However, testing whether coevolution is actually occurring in any specific case is a challenging job.

Smith believes the Joshua tree may offer a way forward for understanding coevolution. What fascinates him about the two species is how the two are dependent on one another for their survival – yucca moths are the only pollinators of Joshua trees, and the yucca moths can reproduce only by laying their eggs in pollinated flowers.

“Without the pollination, the flowers wouldn’t develop and there wouldn’t be seeds for the baby moths,” Smith says. “The intentional pollination is so bizarre. It really is an exciting relationship.”

Although the interaction seems on the surface to be a harmonious one, Smith believes the alliance between yucca moths and Joshua trees is an uneasy one. Both the moths and the trees benefit from the interaction, but they also both pay high costs.

The trees receive extremely reliable pollination without having to produce nectar, but in exchange they must sacrifice some of their seeds to the moth’s caterpillars. Likewise, while the moths gain access to a highly nutritious food source for their young, in exchange they must gather pollen and undertake the dangerous tasks of flying between trees — a journey that is fraught with potential predators.

Smith speculates both the moths and the trees may be evolving to minimize the costs and maximize the benefits. It appears that the Joshua tree’s flowers have evolved over time to limit the number of seeds that can be eaten by the moths, but the moths have evolved to become better at laying their eggs on Joshua trees.

“This relationship is thought to be the holy grail of coevolution, but no one has shown that that’s actually happening,” Smith says.

Smith aims to learn more about this relationship using controlled experiments, and by studying the organisms’ gene sequences to see if the two species are coevolving, and if the right combination of circumstances can lead to the creation of a new species.

Learning Opportunities

To assist in his work, Smith will create a summer research immersion program for Willamette students. Through the program, the undergrads will develop independent research projects and collect field data alongside Smith in Nevada. The program will be open to 12 students per session.

“At the end of the program, students will present their works at national meetings and make connections with graduate schools,” Smith says. “This opportunity is typically reserved for graduate students.”

Smith will also use grant funds to develop community programming with the Desert Institute at Joshua Tree National Park, based in southeastern California. In Nevada, he will host classes, develop a lecture series and invite community members and Willamette students to collect data that will aid his research.

Finally, Smith will create a post-doctoral training program, which will enable a post-doctoral scientist to spend several years working with Smith and learning how to successfully combine teaching and research. The postdoctoral training program will culminate in a six-month appointment as a visiting assistant professor at Willamette.

“I feel like I’m doing the most exciting research of my career,” Smith says. “It’ll take a lot more data before we can say what’s happening here, but I’m very, very optimistic.”