Fowles, a second-year doctoral student in the UC Davis Department of Entomology and Nematology, just received a $15,000 grant from the Environmental Protection Agency for his research on “Beetle Larvae as Biodegraders of Styrofoam and Organic Waste” and now has an opportunity to score a $75,000 grant.
Meanwhile, his 100,000 mealworms in the Briggs Hall lab of his major professor Christian Nansen, are munching away in a project that Fowles hopes will make a difference in breaking down Styrofoam--especially a problem in the nation's landfills--and offer sustainable environmental solutions.
The larvae of the darkling beetle larvae, Tenebrio molitor, eat polystyrene or plastic foam, generically known as Styrofoam, a fact first revealed in 2015 by Stanford University researchers.
“It's about insects processing waste,” Fowles said of his research. “In three weeks they ate three-fourths of a pound of Styrofoam, converting it into biodegradable waste.”
“Trevor's project should be viewed as an example of what entomological agricultural research is all about in the 21st Century--developing new and highly innovative ways to recycle resources and more sustainable food production systems," said agricultural entomologist Christian Nansen, an associate professor of entomology who specializes in applied insect ecology, integrated pest management (IPM) and remote sensing.
In addition, the project has an applied evolutionary angle, which Fowles intends to explore.
Fowles received one of 31 Phase 1 grants in in the National Student Design Competition for Sustainability Focusing on People Prosperity and the Planet (P3), amounting to $463,000 in funding. His project now advances to the Phase 2 level, to take place April 7-8 at the National Sustainable Design Expo at the Science and Engineering Festival in Washington, DC.
In his research project, Fowles seeks to design a pilot-scale styrofoam biodegradation unit to take in regional styrofoam and organic waste, and establish a high-performance beetle lineage, or the “best beetle larvae to do the job.” The adult beetles also eat Styrofoam, but not as much.
“Organization of our food systems will be a defining challenge in the upcoming century and I believe insects will play a significant role in transforming our agricultural sectors,” Fowles said.
His design emphasizes economic feasibility, community engagement, and environmental stewardship. To be sustainable, the project is aimed at connecting local community stakeholders with research expertise to produce an ecofriendly alternative for styrofoam disposal. Fowles is zeroing in on four components to meet these objectives:
- optimizing parameters influencing styrofoam biodegradation
- modeling and designing a pilot system that maximizes degradation and nutritional value of beetle larvae
- project integration in collaboration with local agricultural producers and waste management to meet real world waste demands and
- community engagement to share the novel aspect of this concept and educate local school children about the concepts of sustainability.
After biodegrading the styrofoam, the beetles can be pelletized for animal feed, Fowles said, and the excrement or frass can be used as “high-value amendment to compost mixtures.” He figures that that since Styrofoam by itself is a poor nutrient source for the beetle larvae, he eventually will mix it with organic waste materials, such as, pulp from wine and tomato industries, to optimize beetle development.
The darkling beetles and larvae are pests of stored grains, but the larvae are widely used throughout the world as food for humans; for captive pets, including fish, reptiles and birds; and as fish bait. They are reared commercially on fresh oats, wheat bran or grain, and often with sliced potato, carrots, or apple as a moisture source.
In the wild, darkling beetles and larvae are general decomposers, eating decaying leaves, sticks, grasses, and carcasses.
Fowles said he received his first colony of mealworms in 2016 from then graduate student Tom Nguyen at the Bohart Museum of Entomology, now a researcher at the Smithsonian Institution. Fowles purchased his 100,000 mealworms from the insect farm, Rainbow Mealworms and Crickets in Compton.
Fowles, who grew up in West Sacramento, received his bachelor's degree in biology in 2011 from San Diego State University. Before entering the UC Davis graduate student program, he served as a lab manager for five years for Carroll/Loye Biological Research, launched by the UC Davis entomological team of Scott Carroll and Jenella Loye.
In a news release, EPA Administrator Scott Pruitt said: “This year's P3 teams are applying their classroom learning to create valuable, cutting-edge technologies. This next generation of scientists is designing sustainable solutions that will help protect public health and the environment and ensure America continues to lead the world in innovation and science for decades to come.”
Now, students who enroll in UC Davis biological sciences classes can come face to face with one of them every day.
Keller’s photo of a darkling beetle, Stenomorpha lecontei, graces the cover of the UC Davis edition of Life: The Science of Biology, by David Sadava, David Hillis, H. Craig Heller and May Berenbaum.
Keller captured the image of the beetle laying eggs in a vernal pool at the Carizzo Plain National Monument, San Luis Obispo County, Calif., while it was also eating pygmy weed, Crassula aquatic.
The book, published by Freeman Custom Publishing, New York City, and Sinauer Associates, Inc., Sunderland, Mass. is customized for use by UC Davis instructors.
"Beetles are awe inspiring because they are so different,” said Keller, who is completing her requirements this year for a doctorate in entomology this year. She studies with major professor Lynn Kimsey, director of the Bohart Museum of Entomology and professor of entomology.
“As a human, I and the 7 billion people on the planet are only one species, Homo sapiens," Keller said. "But the insect Order Coleoptera, or beetles, has more than 360,000 species. “Beetles have the greatest diversity of all the insects. Butterflies are big and showy, but beetles can be. too. On a ladybug, which is really a beetle and not a bug, those red and black spotted front wings are called elytra. Beetle elytra are not used for flying so beetles actually fly with one pair of wings. But those elytra help protect them because they can be very tough and sometimes incredibly flashy to warn off predators.”
Keller said that “If you can think of an ecological niche there is probably a beetle there taking advantage of the resources. Believe it or not, there is a beetle that is a parasite and lives in the butt of a beaver. Beetles are truly amazing and although I am partial to the flightless, black tenebrionids, I do collect and appreciate the beauty of all beetles. Okay, maybe I don't collect the beaver butt parasite beetle but wow, who would have thought beetles would be there!”
Keller, who noted that Darwin was an avid beetle collector and enthusiast, acknowledged that she has many "favorite groups of beetles," but "one of my favorites has to be the jewel beetles. Most of them are pests but they are very stunning, hence the name jewel beetle. There are so many different types of beetles that we know of or that have been described but there are still so many that await discovery."
Keller is a researcher, college instructor, mentor, artist, photographer, and author. She recently authored a 35-page children’s book, “The Story of the Dogface Butterfly,” available in the the Bohart Museum gift shop and online at http://www.bohartmuseum.com/the-story-of-the-dogface-butterfly.html
The book, being used in kindergarten through sixth-grade classrooms, and in private and public collections throughout the country, tells the untold story of the California dogface butterfly (Zerene eurydice), and how a classroom successfully mounted a campaign to name it the California state insect. Illustrations by artist Laine Bauer, a UC Davis graduate, and photographs by naturalist Greg Kareofelas, a Bohart Museum volunteer, depict the life cycle of this butterfly and show the host plant, false indigo (Amorpha californica).
Net proceeds from the sale of this book are earmarked for the education, outreach and research programs at the Bohart Museum, located in Room 1124 of the Academic Surge building, Crocker Lane, UC Davis campus.
Her seminar title is "Taxonomy of Stenomorpha Solier, 1836 (Coleoptera: Tenebrionidae: Asidini." Her major professor, Lynn Kimsey, director of the Bohart Museum of Entomology and UC Davis professor of entomology, will host her.
“My research focuses on a very large genus which historically had 88 species and no modern species level work for several taxa for nearly 175 years,” Keller said. “Part of my research focuses on a group of flightless species restricted to the Sierra Transvolcanica or southern Transverse range in Mexico. Using biogeography, morphological analyses and the examination of over 10,500 specimens, I recognize 51 valid species of Stenomorpha Solier, 1836, with seven newly recognized subgenera, while 37 formerly recognized species are synonymized or newly combined."
One of the species that she studies is Stenomorpha costata, which occurs in Mexico and is flightless.
“Certain Stenomorpha species occur in California vernal pools but are not listed as vernal pool species,” she said. She also will discuss the importance of taxonomy in conservation.
If time allows, Keller will discuss her other projects, working in the Bahamas and mentoring students, as well as her recent research on morphology and developmental patterns of gene expression.
Keller received her associate science degree in biology and chemistry, with highest honors from Sacramento City College in 2001 and then transferred to UC Davis where she received her bachelor’s degree in evolution and ecology (2004), and her master’s degree in entomology (2007). She was selected student commencement speaker at her 2004 graduation.
She served as a teaching assistant for a number of courses at UC Davis and has also presented guest lectures, including “Insect Sex and Mating Systems” and “Insects and the Environment—Ecological Physiology.”
As an outreach education project, she authored a children’s book, “The Story of the Dogface Butterfly,” about the California state insect. The book is available at the Bohart Museum of Entomology.
Among her many awards at UC Davis:
- Outstanding Graduate Student Teaching Award, May 2008
- Division of Biological Sciences (DBS) Commencement Speaker, June 2004
- DBS Departmental Citation for Outstanding Achievement in Academics and Research in Evolution and Ecology, Spring 2004
- Outstanding Senior 2004
- Undergraduate Research Conference, Oral Presentation, April 2004
- President’s Undergraduate Fellowship, Spring 2003
Keller has given scores of talks at entomological society meetings, including “Richard M. Bohart: One Hundred Years of Entomologists in the Pacific Northwest,” at the March 2007 meeting of the Pacific Branch, Entomological Society of America (ESA). She organized and chaired or co-chaired three section symposia (2006-2008) at the ESA annual meetings. One of these was on “Systematics and Diversity of Coleoptera” at the ESA meeting in 2008 in Reno.