Melissodes agilis, a long-horned digger bee. (Photo by Kathy Keatley Garvey)

You can find out Wednesday, Oct. 12 at a program on "Bees and Climate Change” at the Häagen-Dazs Honey Bee Haven, located on Bee Biology Road, west of the central campus.

The event, set from noon to 1:30 p.m--and free and open to the public--will include a tour and two speeches. Christine Casey, manager of the honey bee haven, will discuss “Climate Change and the Bee Garden," and Robbin Thorp distinguished emeritus professor of entomology, UC Davis Department of Entomology and Nematology, will cover "Effects of Climate Change on Native Bees."

This is part of the 2016-17 Campus Community Book Project, spotlighting Raj Patel's Stuffed and Starved: The Hidden Battle for the World Food System.

The haven, part of the UC Davis Department of Entomology and Nematology, was installed in the fall of 2009 following a generous donation from Häagen-Dazs, known for its premium ice cream. Approximately half of the company's flavors depend on bee pollination.

The Oct. 12th event is part of a series of tours and open houses scheduled the week of Oct. 11-13. Other tours and open houses for Oct. 11-13:

Tuesday, Oct. 11
Exploring Horticulture Innovations
Noon to 1:30 p.m., Horticulture Innovation Lab Demonstration Center
Tour the low-cost, agricultural technologies that UC Davis researchers are using around the world. Edible plant giveaway to the first 20 visitors.

Wednesday, Oct. 12
Student Farm Tour and Harvest
9 to 10:30 a.m., Student Farm
Join the Student Farm for a special tour and harvest demonstration. Campus and community members are all welcome!

Thursday, Oct. 13
Arboretum Edible Campus Project and World Food Day Information Session
Noon to 1:30 p.m., Plant and Environmental Sciences Salad Bowl Garden
Tour the Salad Bowl Garden and learn more about the Arboretum Edible Campus Project in celebration of World Food Day, which will be Sunday, Oct. 16.

Another upcoming event affiliated with the Campus Community Book Project will feature agricultural entomologist Christian Nansen of the UC Davis Department of Entomology and Nematology. He will speak on "Urban Food Production in the Digital Age--Local Empowerment and Sustainability, on Wednesday, Jan. 18 from noon to 1 p.m. in the Memorial Union.

Those are just some of the events calendared for the academic year and showcasing the Campus Community Book Project. See more events here.

The Campus Community Book Project aims to promote dialogue and build community by encouraging diverse members of the campus and surrounding communities to read the same book and attend related events. The book project advances the Office of Campus Community Relations (OCCR) mission to improve both the campus climate and community relations, to foster diversity and to promote equity and inclusiveness.

For more information on the Campus Community Book Project, visit ccbp.ucdavis.edu.

Doctoral candidate Meredith Cenzer

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."

A lygus bug, one of many agricultural pests. (Photo by Kathy Keatley Garvey)

It's hosted by the UC Davis Department of Biological and Agricultural Engineering, also known as BAE.

"There are steadily growing concerns about how global and sustainable agricultural production and food security can be maintained in the 21st century and beyond," Nansen says. "It is expected that arthropod pest management in agricultural systems will face profound challenges, as pesticides are being faced out, pests are developing resistance to pesticides, and because growing conditions become less predictable due to climate change and diminishing availability of water for crop irrigation"

"Many arthropod pest outbreaks occur in crops initially being exposed to abiotic stress, such as, drought or unbalanced fertilizer applications. In these cases, an arthropod pest outbreak may be a symptom or consequence of sub-optimal crop management regime."

Nansen's presentation is about "remote sensing of crop stress and how it can be used to minimize risk of pest outbreaks, as crop reflectance data provide insight into some of the mechanisms that are driving pest population dynamics, both temporally and spatially."

At UC Davis, Nansen is focusing on four major themes: host plant stress detection, host selection by arthropods, pesticide performance, and use of reflectance-based imaging in a wide range of research applications.

Born and educated in Denmark, Nansen received his master's degree in biology from the University of Copenhagen in 1995 and his doctorate in zoology from the Royal Veterinary and Agricultural University in Denmark in 2000. He accepted positions in Portugal, Benin, United States, UK and Australia before joining the UC Davis Department of Entomology and Nematology in January as an assistant professor. His international experience also includes being an international exchange student at the University of Lisbon, Portugal and a visiting professor at Northwest A&F University, Yangling, China.

“Agricultural entomology has given me so many opportunities to travel and work internationally, and that has been extremely rewarding,” he said. “I am passionate about food production and how to produce food ‘smartly' – so that it is profitable and also environmentally sustainable. And insects are critically important in manipulated food webs, such as, a crop field, forest, orchard, or horticultural greenhouse. I enjoy studying their ecological roles in these systems and how we can use that information to develop smarter ways to produce food.”

“Even though Denmark is a very small country (5 million people),” Nansen said, “it has been at the forefront of agricultural research and production for many decades."

Nansen previously held faculty positions at Texas A&M, Texas Tech, and most recently at the University of Western Australia. As a university employee, the most common way to “create impact” is by influencing the minds and interests of students, but also of particular stakeholders,” he said.

“While working in Texas, we developed a very effective sampling method for an important insect pest in potato fields, and a 4th generation potato grower (Bruce Barrett) actually changed his management strategy because of our sampling method: he purchased the equipment needed and hired people specifically to conduct insect sampling, as he saw how use of this method could save him thousands of  dollars on insecticide sprays--because he would now have a much better idea about when and where to spray. Recently, in Australia we demonstrated to farmers that sub-optimal maintenance of their stored seed grain led to loss of crop vigor and therefore a loss in crop yields. That is, if the seed grain is poorly managed, then stored grain infestations will likely occur, and these beetles will damage the kernels so they don't germinate. We provided simple guidelines for how the grain storage practices could be improved, so quite a few farmers are now following our guidelines to optimize the vigor of their seed grain.”

“Sometimes, we can go further and actually develop tools or gadgets which end-users may find useful. As an example, we have developed a freely available phone app to optimize pesticide spray applications based on weather and spray settings (http://agspsrap31.agric.wa.gov.au/snapcard/). The main goal with this phone app is to guide farmers so that they obtain the best possible spray coverage--to reduce risk of pests developing resistance--and to encourage them NOT to spray pesticides under unfavorable conditions.”

A "mute" cicada. (PLOS ONE journal)

All the more reason to appreciate what Christian Nansen, agricultural entomologist at the University of California, Davis, and two of his colleagues just did.

Nansen and Changquing Luo and Cong Wei, both from China's Northwest A&F University, just published their research on the so-called "mute" cicadas. Are they really mute? If so, how do they communicate and attract mates?

Their work, “How Do ‘Mute' Cicadas Produce their Calling Songs?”, appears in the Feb. 25th edition of PLOS ONE, an open access peer-reviewed scientific journal published by the Public Library of Science.

Cicadas in the genus Karenia lack the specialized sound-producing structures that characterize most cicadas, says  Nansen, an assistant professor in the UC Davis Department of Entomology and Nematology. They have no tymbal mechanism.

But they are not mute.  “They do indeed produce sounds,” he says.

In ground-breaking research, the scientists discovered a new sound-production mechanism in Karenia caelatata, which produces impact sounds by banging the forewing costa against the operculum. It's somewhat like beating a drum while other cicada species with tymbal mechanisms play an orchestra of diverse and loud sounds.

“As part of quantifying species' differences in behavior, we used hyperspectral imaging of forewing costae and demonstrated that high-spectral resolution imaging can reveal distinct patterns, such as difference between mute and normal cicadas,” Nansen explained. “So application of such imaging technologies may become a ‘bridge' between in-depth field behavioral research and detailed physiology and histology (structural studies) of insect body parts.”

In their publication, the researchers described the temporal, frequency and amplitude of the sound produced. They also posted the sound on YouTube,

 “Morphological studies and reflectance-based analyses reveal that the structures involved in sound production of K. caelatata (i.e., forewing, operculum, cruciform elevation, and wing-holding groove on scutellum) are all morphologically modified,” they wrote. “Acoustic playback experiments and behavioral observations suggest that the impact sounds of K. caelatataare used in intraspe­cific communication and function as calling songs.” 

“The new sound-production mechanism expands our knowledge on the diversity of acoustic signaling behavior in cicadas and fur­ther underscores the need for more bioacoustic studies on cicadas which lack tymbal mechanism,” they concluded in their abstract. 

Cicadas, also known as “tree crickets” (from Latin cicada), are among the most widely recognized of insects due to their large size (usually 2 to 5 centimeters or more) and loud sound. They live in warm climates, from temperate to tropical. Immature cicadas spend most of their lives sucking juice from tree roots. The adults suck plant juices from stems.

The best-known North American genus, Magicicada, has a long life cycle of 13 or 17 years and emerges in great numbers.

Nansen joined the UC Davis Department of Entomology and Nematology in January. He is focusing on four major themes: host plant stress detection, host selection by arthropods, pesticide performance, and use of reflectance-based imaging in a wide range of research applications.

Already he is using his international expertise to zero in on more sustainable farming systems, better food production and fewer pesticides.

“The agricultural sector in California is so exciting, because of its diversity and economic importance,” said Nansen, whose agricultural entomology expertise encompasses seven countries including his native Denmark. “Secondly, there is a strong spirit of innovation in this region, and I hope to contribute to the development of highly advanced crop monitoring systems and decision support tools, so that farming practices can become less reliant on pesticides.”

“I also believe that the strong academic programs at UC Davis with ecology and evolution are of incredible value, and that we can integrate the basic theory from these disciplines into the fundamental of crop management to obtain more sustainable farming systems,” Nansen said. “As an example of a line of research I am interested in – application of fertilizers obviously affect crop growth, but they also affect the attractiveness of crops to many insect pests, and they influence the ability of plants to resist attacks by several important insect pests.”

“So, how can we optimize use of crop fertilizers to stimulate yields but also minimize risks of pest infestations? The answer to such a question is underpinned by in-depth understanding about host selection ecology and about fitness and evolutionary processes involved in host adaptation. In other words, it is critically important to demonstrate how we can use studies of agricultural systems to learn about the ecology of species and their food webs and evolutionary processes.”

Born and educated in Denmark, Nansen received his master's degree in biology from the University of Copenhagen in 1995 and his doctorate in zoology from the Royal Veterinary and Agricultural University in Denmark in 2000. He accepted positions in Portugal, Benin, United States, UK and Australia before coming to UC Davis. His international experience also includes being an international exchange student at the University of Lisbon, Portugal and a visiting professor at Northwest A&F University, Yangling, China.

As part of his undergraduate studies, Nansen took time off to travel to Brazil to write a book about sustainable agriculture in rainforest areas. “In this process, I learned about the potential of honey bees as both pollinators of crops but also as ‘promoters' more broadly of sustainable agricultural development,” Nansen said.

Nansen wrote his master's thesis on honey bees: “The Apis mellifera Forging Response to the Pollen Availability in Cistus salvifolius.” The plant isalso known as a sage-leaved rock rose or Gallipoli rose. He conducted field work in Portugal involving pollen identification, observations on daily flight and foraging activity, and modeling of pollen availability.

For his doctorate, his interest turned to the larger grain borer, a serious pest of stored maize and dried cassava roots. He wrote his dissertation on “The Spatial Distribution and Potential Hosts of the Larger Grain Borer, Prostephanus truncatus (Horn) (Coleoptera: Bostrichidae), in a forest in Benin, West Africa.” His research involved stored product insect ecology, field trapping with pheromone traps, experimental work on pheromone production, vegetation analysis, satellite image interpretation, laboratory infestation of potential breeding substrates, and histological studies.

“Agricultural entomology has given me so many opportunities to travel and work internationally, and that has been extremely rewarding,” he said. “I am passionate about food production and how to produce food ‘smartly' – so that it is profitable and also environmentally sustainable. And insects are critically important in manipulated food webs, such as, a crop field, forest, orchard, or horticultural greenhouse. I enjoy studying their ecological roles in these systems and how we can use that information to develop smarter ways to produce food.”

Read more about Nansen and his work on the UC Davis Department of Entomology and Nematology website and on his faculty website.