That's what postdoctoral scholar Bodil Cass of the Jay Rosenheim lab, University of California, Davis, will discuss at her seminar from 4:10 to 5 p.m., Wednesday, Oct. 25 in 122 Briggs Hall, UC Davis campus. Admission is free, and the seminar is open to all interested persons.
"Citrus is a major agricultural industry in California with a established integrated pest management (IPM) program," she says. "However, the IPM guidelines for citrus are based on years of experience and careful field research in navel oranges, and have not been updated to accommodate the recent dramatic increase in mandarin acreage in the San Joaquin Valley. We know oranges and mandarins are very different plants, but not which practices need to be modified to effectively control pests in mandarins."
Cass says that updating the IPM guidelines for "a new citrus species is a substantial challenge, given the scale and pace of citrus production. We are using a combination of ecoinformatics--data mining of pest management records provided by cooperating citrus growers--and field experiments to expand our understanding of the arthropod pest complex in California citrus. Analyses of the historical commercial data indicate that fork-tailed bush katydids, Scudderia furcata, which are a key pest in oranges, very rarely damage some species of mandarin. We are using field experiments to test hypotheses to explain this intriguing observation, and to determine whether katydids are indeed a pest at all in mandarins."
A native of the state of Queensland, Australia, Cass is an accomplished scholar who holds several degrees:
- A bachelor's degree (2005) from the University of Queensland, where she graduated with high distinction and a dean's commendation for high achievement. (She completed the Advanced Studies Program in Science in 2005, and the Enhanced Studies Program in Chemistry, 2012)
- Honors Integrative Biology (2006), University of Queensland, with high distinction and valedictorian
- Doctorate in Interdisciplinary Program in Entomology and Insect and minor in ecology and evolutionary biology (2015) from the University of Arizona (4.0 GPA)
Cass joined the lab of Jay Rosenheim, UC Davis professor of entomology, in 2016, and also serves as an associate in the Center for Population Biology at UC Davis. She has published her work in Oecologia, Biological Journal of the Linnean Society, Microbial Ecology, Research in Microbiology, Science, and PLoS Genetics, PLoS Biology and PLoS Pathogens, among other journals.
A member of the Entomological Society of America (ESA), Cass delivered oral presentations at the ESA annual conferences in 2011 and 2015, and also at the 2016 International Congress of Entomology (ICE), co-chaired by UC Davis chemical ecologist Walter Leal and held last September in Orlando, Fla. She is the co-principal investigator of a 2017 grant awarded by the Citrus Research Board.
Cass has also won a number of fellowships and awards, including national awards in the P.E.O. International Peace Scholarship Program in both 2008 and 2009.
It's not at all surprising that one of the many awards she won in the beginning of her career was the "Smart Women, Smart State Award" in the undergraduate category, statewide competition (Queensland) in 2005.
He feuded with fellow entomologists, was a bigamist (married to two wives at the same time) and caused an uproar when a tunnel he dug in a Washington, D.C. alley collapsed in 1924 and some declared it the work of German spies.
All that will come to light on Thursday, April 28 at UC Davis when entomologist Marc E. Epstein talks about his newly published book on Dyar's eccentric life, Moths, Myths and Mosquitoes: The Eccentric Life of Harrison G. Dyar, Jr.
Epstein will present a lecture and book signing from 7:15 to 8:45 p.m., in the International House, 10 College Park, Davis.
The event, free and open to the public, is co-sponsored by Jay Rosenheim, professor of entomology, UC Davis Department of Entomology and Nematology, and by his department. Epstein is a longtime research associate and friend of Rosenheim's.
“As far as how I got into doing research on Dyar, at the onset it was related to my dissertation at University of Minnesota on Limacodidae (family of slug caterpillar moths, so called because their caterpillars bear a distinct resemblance to slugs),” Epstein said.
This led to Epstein and Henson to writing the American Entomologist article “Digging for Dyar: the Man behind the Myth.”
“Since the article appeared in 1992 I've accumulated a lot more information about Dyar, his genealogy, and even more significant connections between him and his favorite moths,” Epstein said.
The book, published by Oxford University Press, will be available for purchase at Epstein's talk.
Epstein is a senior insect biosystematist for the order Lepitopdera (butterflies, moths) with the Plant Pest Diagnostics Branch, California Department of Food and Agriculture. He is a research associate for the National Museum of Natural History (NMNH), Smithsonian Institution.
Harrison G. Dyar Jr. (1866-1929) was a Smithsonian entomologist of the early 20th century. He was a taxonomist who published extensively on moths and butterflies, mosquitoes, and sawflies. As a teenager, he studied insects, particularly moths. He received his bachelor's degree in chemistry in 1889 from the Massachusetts Institute of Technology, and his master's degree in biology from Columbia University in 1894. His doctoral dissertation (1895) dealt with airborne bacteria in New York City.
Oxford University offers this description of Moths, Myths and Mosquitoes:
"On September 26, 1924, the ground collapsed beneath a truck in a back alley in Washington, D.C., revealing a mysterious underground labyrinth. In spite of wild speculations, the tunnel was not the work of German spies, but rather an aging, eccentric Smithsonian scientist named Harrison Gray Dyar, Jr. While Dyar's covert tunneling habits may seem far-fetched, they were merely one of many oddities in Dyar's unbelievable life."
"For the first time, insect biosystematist Marc E. Epstein presents a complete account of Dyar's life story. Dyar, one of the most influential biologists of the twentieth century, focused his entomological career on building natural classifications of various groups of insects. His revolutionary approach to taxonomy, which examined both larval and adult stages of insects, brought about major changes in the scientific community's understanding of natural relationships and insect systematics. He was also the father of what came to be known as Dyar's Law, a pragmatic method to standardize information on insect larval stages as they grow. Over the course of his illustrious career at the U.S. National Museum, Smithsonian Institution from 1897-1929, Dyar named over 3,000 species, established the List of North American Lepidoptera, an unrivaled catalog of moths and butterflies, and built one of the nation's premier Lepidoptera and mosquito collections."
Epstein researches and writes on evolution and classification of moths and their biodiversity, and develops identification tools for moths that threaten agriculture. He served with NMNH's Department of Entomology (1988-2003), co-founding the department's Archives and Illustration Archives. He received his master's degree (1982) and doctorate (1988) from the University of Minnesota.
For more information on the April 28th event, contact Jay Rosenheim at firstname.lastname@example.org.
Male praying mantids looking for "a little love" don't always fare well. Sometimes they lose their head. Female mantids can--and do--cannibalize them before, during or after copulation.
Now mantid researcher Katherine Barry of Macquarie University, Sydney, Australia, says that some hungry female mantids are deceptive liars. They emit chemical cues, or pheromones, as if seeking a mate, but what they want is not a mate, but a meal. Her research, "Sexual Deception in a Cannibalistic Mating System? Testing the Femme Fatale Hypothesis," appears in the Dec. 17 edition of the Proceedings of the Royal Society B.
The starving females in her study produced the same chemical cues that the well-fed females did. The deception clearly worked. “The consumption of one male improves body condition by approximately 33 percent and fecundity by approximately 40 percent," Barry pointed out.
In her abstract, Barry wrote: "The Femme Fatale hypothesis suggests that female mantids may be selected to exploit conspecific males as prey if they benefit nutritionally from cannibalism. Such a benefit exists in the false garden mantid Pseudomantis albofimbriata—females use the resources gained from male consumption to significantly increase their body condition and reproductive output. This study aimed to examine the potential for chemical deception among the subset of females most likely to benefit from cannibalism (poorly fed females). Females were placed into one of four feeding treatments (‘Very Poor', ‘Poor', ‘Medium' and ‘Good'), and males were given the opportunity to choose between visually obscured females in each of the treatments. Female body condition and fecundity varied linearly with food quantity; however, female attractiveness did not. That is, Very Poor females attracted significantly more males than any of the other female treatments, even though these females were in significantly poorer condition, less fecund (in this study) and more likely to cannibalise (in a previous study). In addition, there was a positive correlation between fecundity and attractiveness if Very Poor females were removed from the analysis, suggesting an inherently honest signalling system with a subset of dishonest individuals. This is the first empirical study to provide evidence of sexual deception via chemical cues, and the first to provide support for the Femme Fatale hypothesis."
We've seen scores of praying mantids lurking, snagging prey, and devouring their prey, but we've never seen any engaging in sexual cannibalism, which occurs when a female cannibilizes the male before, during or after copulation.
Professor Jay Rosenheim of the Department of Entomology and Nematology, University of California, Davis, has.
In fact, he captured an amazing photo of it and posted it on his website. His daughter, Leah, found the pair in their garden. "Note that the larger female has consumed the head of the smaller male (an example of the famous sexual cannibalism that can occur in this species," Rosenheim wrote. "Amazingly, the decapitated male continued to cling to the female and even attempt to re-initiate copulation several times."
With his permission, we're posting his photo below. We're adding two photos typically seen: a praying mantis waiting for prey--or a mate?--in a bed of cosmos, and another of a gravid praying mantis climbing a bamboo stake.
We don't know if a male lost its head during the male-female encounter, but we do know that we have an ootheca or egg case on our back porch.
Thank you, Mrs. Mantis!
As its name implies, it's native to Asia. It was first detected in North America in Wisconsin in July 2000. Technically, it’s Aphis glycines Matsumura. In lay language, that's spelled "p-e-s-t."
Now found throughout much of the Midwest, it sucks.
With its mouthparts.
Enter George Heimpel, professor of entomology at the University of Minnesota's Department of Entomology. Heimpel, who received his doctorate in entomology in 1995 from UC Davis, will return to the UC Davis campus Wednesday, Dec. 4 to speak on “Specificity and the Process of Biological Control Using Aphid Parasitoids."
His seminar takes place from 4:10 to 5 p.m. in 122 Briggs Hall. It is scheduled to be recorded for later posting on UCTV. (Editor's Note: The seminar was initially scheduled for noon, but due to midwest storms, Heimpel's flight was delayed.)
"Over the past 25 years or so, importation ('classical') biological control of arthropod pests has undergone a paradigm shift in which emphasis has shifted from an exclusive focus on efficacy to a focus on the actual and potential risks of biological control introductions," Heimpel says. "Host specificity testing is the cornerstone of risk assessment in this new paradigm, and only highly specialized agents are currently approved for release. Here, I describe the process of importation biological control of an invasive agricultural pest in the North-Central U.S.--the Asian soybean aphid."
"Numerous parasitoid species were imported from Asia as potential biological control agents and I focus on five species for which host-specificity testing was done," he says. "Each of these three species tells a different story in terms of host-specificity, the potential for biological control efficacy, and actual success of field releases. Together, these case studies illustrate some potential relationships between safety and efficacy in biological control, and the importance of various traits in mediating safety and efficacy of biological control agents."
Born in Germany, Heimpel grew up mainly in California. He received his bachelor’s degree in conservation and resource studies in 1988 from UC Berkeley and his master's degree in 1991 in entomology and applied ecology from the University of Delaware before heading over to Jay Rosenheim's lab at UC Davis to receive his doctorate in 1995. Heimpel then spent two years as a USDA post-doctoral fellow at the University of Wisconsin in Mike Strand’s lab.
Heimpel now teaches biological control and insect behavior.
And one of his targets is the Asian soybean aphid.
It's exciting to see a promising career unfold.
We first met UC Davis graduate student Alex Van Dam in 2010 when he received a $12,000 award from the University of California Institute for Mexico and the United States (UC MEXUS), an academic research institute dedicated to encouraging, securing, and contributing to binational and Latino research and collaborative academic programs and exchanges.
Then later in 2010 he received a Robert and Peggy van den Bosch Memorial Scholarship for his research on a scale insect. His project: "Investigating Host-Associated Lineage Splitting Within Dactylopius Using Molecular Phylogenetics."
Now Van Dam has just been selected for a National Science Foundation (NSF) Postdoctoral Fellowship to work on insect/host plant research.
The postdoctoral fellowship award is supported by both the Directorate for Biological Sciences and the Office of International Science and Engineering at NSF. During his two-year fellowship, he will work on a project, “New Insights into Insect Host-Plant Generalization: Population Transcriptome Sequencing of Porphyrophora spp.,” under the sponsorship of Uffe H. Mortensen at the Department of Systems Biology, Technical University of Denmark.
Van Dam will identify genes responsible for host-plant range in scale insects, and how they are maintained across populations. “This will be accomplished by testing hypotheses delineating physiological genes responsible for insect host-plant generalization,” he said. “Host-plant generalization is the ability to feed on many different species of plants. I will test if increased dispersal of host-plant detoxification genes in generalists leads to maintenance of functional gene paralogs, that is, gene duplications, across large effective populations.
A native of Los Angeles, Van Dam received his bachelor's degree and master's degree in entomology at UC Riverside and is currently a doctoral candidate and a member of the Entomology Graduate Group. He studies with major professor Bernie May in the Department of Animal Science. Professors Jay Rosenheim and Steve Nadler of the Department of Entomology are members of his dissertation committee.
Meanwhile, Van Dam is gearing up for his exit seminar at the Animal Science Spring Seminar Series. He'll present his seminar on Monday, April 29 from 12:10 to 1 p.m. in Weir Room 2154, Meyer Hall.
Another great success story!