The UC Davis Department of Entomology and Nematology has announced the list of speakers for the fall seminars. Agricultural entomologist and seminar coordinator Christian Nansen said the topics include everything from soapberry bugs to monarchs.
Instead of the previous noon-hour seminars, however, there's a change in the time: they're from 4:10 to 5 p.m. on Wednesdays in Room 122 of Briggs Hall, Kleiber Hall Drive.
Doctoral candidate Meredith Cenzer will speak on "Ecological and Evolutionary Interactions Between Soapberry Bugs (Jadera Haematoloma) and Their Host Plants" at the next UC Davis Department of Entomology and Nematology seminar, set from 4:10 to 5 p.m., Wednesday, Oct. 5 in 122 Briggs Hall. This is her exit seminar.
Soapberry bugs are a classic evolutionary example of how rapidly insects can switch hosts, adapting from a native to an invasive plant, she says.
Her newly published UC Davis research shows that soapberry bugs have not only lost adaptations to their native host plant but are regionally specializing on an invasive host. (Read about her latest publication here.)
The October-November schedule:
Wednesday, Oct. 5:
Meredith Cenzer, doctoral candidate, Louie Yang lab
Topic: ""Ecological and Evolutionary Interactions Between Soapberry Bugs (Jadera Haematoloma) and Their Host Plants" (exit seminar)
Wednesday, Oct. 12:
Howard Ferris, professor of nematology, UC Davis Department of Entomology and Nematology
Topic: "Roles of Nematodes in Soil Ecology and Soil Health"
Wednesday, Oct. 19
Justin Whitehill, postdoctoral research associate
University of British Columbia, Vancouver, Canada
Topic: "Carbon Castles and the Physical Defense of Conifers Against Insect Invaders"
Wednesday, Oct. 26
Marek Borowiec, doctoral candidate, Phil Ward lab
Topic: "Genomic Data and the Tree of Life: Known Knowns, Known Unknowns, and Unknown Unknowns of Army Ant Evolution" (exit seminar)
Wednesday, Nov. 2
Sandy Olkowski, doctoral candidate, lab of Thomas Scott (now emeritus professor of entomology)
"Temporal Inconsistency of Dengue Fever Surveillance in Iquitos, Peru" (exit seminar)
Wednesday, Nov. 9
Hugh Dingle, emeritus professor, UC Davis Department of Entomology and Nematology
Topic:"Monarchs in the Pacific: Contemporary Evolution or Local Ecology?"
Wednesday, Nov. 16
Diane Ullman, professor, UC Davis Department of Entomology and Nematology
Topic: "Thrips Salivary Glands: The Relevance of Tissue Tropism and Gene Expression to Tospovirus"
Wednesday, Nov. 30
Phil Ward, professor, UC Davis Department of Entomology and Nematology
Topic: "Exploring the Ant Tree-of-Life"
Wednesday, Dec. 7
Francis Ratnieks, professor of apiculture, University of Sussex, United Kingdom
"How Can We Help Bees Via Research? The Sussex Plan for Honey Bee Health and Well Being."
Forget the soaps; let's talk about soapberry bugs and an entomologist at the University of California, Davis, who studies them.
And why and how she decided to pursue entomology as a career. That we'll save until the end of this blog.
Doctoral candidate Meredith Cenzer of the Louie Yang lab, UC Davis just published her research on soapberry bugs, which are a classic evolutionary example of how rapidly insects can switch hosts, adapting from a native to an invasive plant.
Her research shows that soapberry bugs have not only lost adaptations to their native host plant but are regionally specializing on an invasive host.
The work, "Adaptation to an Invasive Host Is Driving the Loss of a Native Ecotype," published in the current edition of the journal Evolution, “collapses a classic and well-documented example of local adaptation,” said doctoral candidate Meredith Cenzer of the Louie Yang lab, UC Davis Department of Entomology and Nematology. The plant-host switch can lead to disruption of native plant communities and a breakdown of the ecosystem.
The players involved are the soapberry bug (Jadera haematoloma), also known as “the red-shouldered bug”; its native host plant, the balloon vine (Cardiospermum corindum), and the invasive host, the golden rain tree or Taiwanese rain tree (Koelreuteria elegans).
The study, which took place in Florida, expands on the 1989 groundbreaking research of UC Davis evolutionary ecologist and soapberry expert Scott Carroll, who documented local adaptation in beak length, survival, and development time and other traits between soapberry bugs, balloon vine and the golden rain tree in Florida.
Said Carroll: "Meredith Cenzer's findings carry an important message for those concerned with biodiversity conservation, because she shows that even highly distinct adaptive specializations can disappear rapidly due to human influence on the environment– even in cases where the key native habitat has not been lost."
The soapberry bug, which lives throughout the United States and much of the world, feeds on seeds within the soapberry plant family, Sapindaceae, which includes soapberries, boxelders and maples. Mostly black, it has red eyes, red lateral stripes on the sides of its head and red on its “shoulders” (pronotum). It is often mistaken for the boxelder bug.
“As part of my doctoral dissertation, I documented that this pattern of local adaptation has been lost in the last 27 years,” Cenzer said, “and that all populations of soapberry bugs in Florida-- even those still found on the native --are now adapted only to the invasive host.“
“Locally adapted populations are often used as model systems for the early stages of rccological speciation, but most of these young divergent populations will never become complete species,” Cenzer noted in her abstract. “The maintenance of locally adapted populations relies on the strength of natural selection overwhelming the homogenizing effects of gene flow; however, this balance may be readily upset in changing environments.”
“All populations that were adapted to the native host--including those still found on that host today--are now better adapted to the invasive host in multiple phenotypes,” she wrote in her abstract.” Weak differentiation remains in two traits, suggesting that homogenization across the region is incomplete. This study highlights the potential for adaptation to invasive species to disrupt native communities by swamping adaptation to native conditions through maladaptive gene flow.”
Cenzer characterized local adaptation as “high performance in one habitat coming at the cost of performance in other habitat types, such that populations specialized on each habitat will have higher fitness in that environment than immigrants from other habitats.”
“This results directly in two types of ecological reproductive isolation between locally adapted populations: 1) selection against migrants, who will be outcompeted by residents, and 2) selection against hybridization (if hybrids show intermediate phenotypes), as hybrid offspring will be outcompeted in each habitat by one parental type,” she wrote in her research paper. “However, such reproductive isolation relies on ongoing differential selection balanced with low rates of gene flow between habitats. In most well studied systems demonstrating local adaptation, we do not know how perturbation – either to selection pressures or gene flow – will influence the long-term stability of differentiation.”
Carroll, who maintains a website, “Soapberries of the World,” says the soapberry bugs are “very approachable native guides to how evolution is taking place on earth day.” His website shows “how evolution happens every day and why it matters.”
How did Meredith Cenzer, a native of Gainesville, Fla., become interested in entomology? We love her answer.
"I first became interested in entomology as a kid," she recalled. "The defining moment in my memory is when my gifted science teacher, Ms. Linda Osborne, told me in third grade that there are people who study insects for a living and that they're called entomologists. She was going to put me in timeout for being too loud (a lifelong problem), but told me she'd let it slide this time if I promised to become an entomologist."
"Two years later, she let me come in and teach her first graders about insects. For my first science fair project, in sixth grade, I tracked the progress of tent caterpillar aggregations; we weren't allowed to manipulate animals, so I photographed them every day and made notes on their behavior - my parents still have the poster from that one."
So, she promised her teacher she'd become an entomologist. And she kept her promise. She received her bachelor of science degree in entomology at the University of Florida in 2009.
Future plans, after receiving her doctorate in entomology from UC Davis?
“I am broadly interested in evolutionary ecology, particularly in plant-insect interactions, and the balancing roles of selection, gene flow, and plasticity on determining the phenotypes we see in nature,” she said. After receiving her doctorate in entomology from UC Davis in the fall, she will start a postdoctoral position at Florida State University with biology professor Leithen M'Gonigle, developing theory on the evolution of dispersal in patchy landscapes.
A tip of the insect net to Meredith Cenzer!
(Editor's Note: Meredith Cenzer participated in the Entomological Society of America's Linnaean Games competition in 2011. See Bug Squad blog of Nov. 22, 2011.)
Quick! What's the answer to this question?
"I am a blood feeder; I have no hair but have a comb. What am I?"
That was the final question posed when the University of California, Davis competed Monday night with the University of Hawai-Manoa team for the championship of the Linnaean Games, Pacific Branch of the Entomological Society of America (PBESA).
The Linaean Games are college bowl-type games featuring questions about insects, entomologists and entomological facts. Each branch of the Entomological Society of America (ESA) can send two teams to the nationals. This year ESA meets in Reno Nov. 13-16.
So, UC Davis and the University of Hawaii are in a dead heat at the PBESA meeting in Hawaii. Tied game. Buzzers ready. And then comes that final question. "What am I?"
"A flea," Emily Symmes of the UC Davis team correctly answers.
Yes, a flea! A flea, indeed.
Emily Symmes, who is studying for her doctorate with major professor Frank Zalom, joined the winners' circle with her fellow teammates who also did equally well: Matan Shelomi, studying for his doctorate with major profesor Lynn Kimsey; Meredith Cenzer, studying for her doctorate with major professor Louie Yang; and James Harwood, studying for his doctorate with major professor James R. Carey.
Winning at the branch level is indeed an accomplishment, as well as a fun endeavor. The PBESA encompasses 11 U.S. states (Alaska, Arizona, California, Hawaii, Idaho, Montana, Nevada, Oregon, Utah, Washington and Wyoming); several U.S. territories, including American Samoa, Guam and the Northern Mariana Islands; and parts of Canada and Mexico.
If you've never been to any of the Linnaean Games, you can see videos online by Googling "Linnaean Games." See if you can answer those questions.
Might be another question about fleas in there, too.
Ask any entomology student and it means "Bring Your Own Bug."
And that's exactly what the UC Davis Linnaean Team did this morning during an interview with the TV anchors of Good Day Sacramento.
By request, the team members brought along their favorite bugs: Madagascar hissing cockroaches (see hisser at right) and assorted walking sticks, all from the Bohart Museum of Entomology; and soapberry bugs from professor Sharon Lawler's lab, UC Davis Department of Entomology.
The TV station labeled the event "a bug invasion."
And indeed it was.
Extension entomologist Larry Godfrey of the UC Davis Department of Entomology faculty coaches the team, which includes graduate students Andrew Merwin (who studies with major professor Michael Parrella, professor and chair of the Department of Entomology), Meredith Cenzer (major professor Louie Yang), Matan Shelomi (major professor Lynn Kimsey, director of the Bohart Museum of Entomology) and prospective graduate student Ralph Washington, who received his bachelor's degree in entomology from UC Davis in 2010.
They competed last December in the national Linnaean Games, a college-bowl type competition that's a traditional part of the Entomological Society of America's annual meeting. Teams answer questions about insects and entomologists and compete for the championship. Ohio State University won the 2010 championship, defeating the University of Nebraska.
But, back to the bugs at the TV station...
Godfrey quizzed the anchors on their knowledge of insects. Each time an anchor answered a question incorrectly, he received temporary custody of a bug.
The final score: Bugs 3; Anchors, 0.
Name the title of the Robert Frost poem that includes this line: “An ant on a table cloth ran into a dormant moth of many times his size.”
No, not "Ants in Your Pants." The answer: “Departmental.”
Another question: “What insect was used as a symbol for the film, The Silence of the Lambs, and what is unusual about the insect’s food habits?”
"No, little more detail, little more detail,” Godfrey coaxed. The answer. “Death’s-Head Hawkmoth” and it raids bee hives (Apis mellifera) for the honey.
The third question dealt with the vedalia beetle: “Where was the vedalia beetle released for the control of cottony cushion scale and what industry did it save?”
“The Southeast" and "Cotton"? No.
“It was released in California," Godfrey said, "and it saved the citrus industry."
The UC Davis team now heads to the next competition, the Linnaean Games at the ESA Pacific Branch meeting, set March 27-30 in Hawaii. Each ESA branch can send two teams to the nationals. Reno is hosting the ESA's 59th annual meeting Nov. 13-16.
Meanwhile, the Bohart Museum should be drawing lots of visitors. It's located at 1124 Academic Surge on California Drive, UC Davis. Admission is free. Visiting hours: Mondays through Thursdays. Times: 9 a.m. to 12 noon and 1 to 5 p.m.
Pop quiz: How many bugs at the Bohart? More than 7 million specimens. Plus, there's the "live petting zoo" where you can touch the hissers and walking sticks...including the ones on the TV show...