- Author: Kathy Keatley Garvey
But there's much more to it than that. What's in that floral nectar and pollen?
Think plant-pollinator-pathogen webs.
Rebecca Irwin, professor of applied ecology at North California State University, Raleigh, is traveling to UC Davis to present a seminar on "The Role of Floral Traits in Pollination and Bee Disease Transmission."
Her seminar, hosted by the UC Davis Department of Entomology and Nematology, is set for 4:10 p.m., Wednesday, Oct. 16 in 122 Briggs Hall. Community ecologist Rachel Vannette, assistant professor and coordinator of the weekly seminars, will introduce her.
"Secondary compounds play a critical role in plant defense against herbivores," says Irwin in her abstract. "Although these compounds can increase plant resistance to herbivore feeding, they can also benefit herbivores by reducing parasitism. There is now widespread evidence that these same secondary compounds are also found in floral nectar and pollen."
"I will share multiple lines of evidence from a variety of collaborative projects in the lab and field suggesting that floral secondary compounds can reduce parasitism in bees, and that bees may be able to selectively forage on flowers with these compounds when they are parasitized," Irwin says. "Because floral secondary compounds alter pollinator behavior, they also have the potential to affect patterns of pollen movement and plant fitness. However, evidence suggests different effects across plant species. Finally, I will share with you results exploring the degree to which secondary compounds and other floral traits affect pollinator disease transmission in the field. Taken together, this seminar will provide empirical evidence into the diversity of roles that secondary compounds, and floral traits more generally, can play in plant-pollinator-pathogen webs."
Irwin, who received her doctorate from the University of Vermont, says on her website that the Irwin lab combines "concepts and techniques from studies of plant-pollinator and plant-herbivore interactions to understand the ecological and evolutionary consequences of pollination mutualisms and how they will respond to environmental change. We also study the disease ecology and transmission biology of bees and their pathogens."
Irwin also shares her expertise on bee condos or bee hotels. "From humble coffee cans to fancier hotels with a roof, there are many ways to get creative with the design. Here, we provide a brief introduction into building a simple first time bee hotel."
And, she says, "hotels work better when facing southeast."
if you want to build your own bee housing units, check out the information on her website.
- Author: Kathy Keatley Garvey
The late Robbin Thorp, the renowned UC Davis distinguished emeritus professor of entomology and global bee authority who will be memorialized at a celebration of life on Friday, Oct. 11 at 6 p.m. in the Putah Creek Lodge, UC Davis, began his career studying honey bees.
Professor Thorp, who served as a member of the UC Davis entomology faculty for 30 years, from 1964-1994, continued to engage in research, teaching and public service until a few weeks before his death on June 7. In his retirement, he co-authored two books, both in 2014: Bumble Bees of North America: An Identification Guide and California Bees and Blooms: A Guide for Gardeners and Naturalists.
Thorp was a tireless advocate of pollinator species protection and conservation and known for his expertise, dedication and passion in protecting native pollinators, especially bumble bees, and for his teaching, research and public service. He was an authority on pollination ecology, ecology and systematics of honey bees, bumble bees, vernal pool bees, conservation of bees, native bees and crop pollination, and bees of urban gardens and agricultural landscapes.
The distinguished emeritus professor was also an authority on honey bees.
Said Eric Mussen, Extension apiculturist emeritus: "We should not forget that Robbin originally was hired to work on honey bees, and he did. His greatest area of expertise was the use of honey bees in almond pollination. Robbin determined that until the colonies reached the population size of six frames of bees, they did not have enough spare bees to serve as foragers (pollinate almonds) since they were all needed to keep the brood warm."
"He also noted that the amount of pollen collected by the bees in a colony was pretty much in direct proportion to colony size, peaking at between 10 and 12 frames of bees," Mussen said. "It was obvious to Robbin that the bees still visited almond blossoms for nectar, days after there was no pollen left in the flowers and the stigmata were no longer young enough to be pollinated. Other studies determined which blossoms along the branches were pollinated earlier and later during the season. All of those studies were very well designed and the results contributed significantly to our recommendations to growers and beekeepers for obtaining maximum benefit from the bees."
“Robbin's scientific achievements during his retirement rival the typical career productivity of many other academic scientists,” said Steve Nadler, professor and chair of the UC Davis Department of Entomology and Nematology. “His contributions in support of understanding bee biodiversity and systematics are a true scientific legacy.” (See more about Robbin Thorp)
Robbin Thorp was a treasure, a gem in the entomological world of bees and beyond.
- Author: Kathy Keatley Garvey
And now doctoral candidate John Mola of the Neal Williams lab, UC Davis Department of Entomology and Nematology, will present his exit seminar on "Bumble Bee Movement Ecology and Response to Wildfire" at 4:10 p.m., Wednesday, Oct. 9 in Room 122 of Briggs Hall.
Mola, who specializes in bee biology, pollinator ecology and population genetics, says in his abstract:
"Observing bumble bees on flowers can be a deceptive practice. When standing in a field looking at a bunch of bees, we have little clue about the distances they traveled to get there or the number of colonies to which the individuals belong. However, modern genetic tools let us reveal this unseen information. In my dissertation I use genetic mark-recapture to understand two areas of general ecological interest and apply them to bumble bees: organismal movement and disturbance ecology. In this talk I discuss what I learned about bumble bee movement ecology in a subalpine meadow complex and insights gained from an unexpected opportunity to study the response of a bumble bee population to wildfire."
Mola holds a bachelor of science degree in environmental studies from Florida State University, and a master's degree in biology at Humboldt State University. He enrolled in the UC Davis Ph.D. program in ecology in 2014.
In August 2019 Mola published a "Review of Methods for the Study of Bumlbe Bee Movement" in Apidologie with his major professor, co-author and pollination ecologist Neal Williams. The abstract:
"Understanding animal movement is critical for conservation planning, habitat management, and ecological study. However, our understanding is often limited by methodological constraints. These limitations can be especially problematic in the study of ecologically and economically important pollinators like bumble bees, where several aspects of their biology limit the feasibility of landscape-scale studies. We review the methods available for the study of bumble bee movement ecology, discussing common limitations and tradeoffs among several frequent data sources. We provide recommendations on appropriate use for different life stages and castes, emphasizing where recent methodological advances can help reveal key components of understudied parts of the bumble bee life cycle such as queen movement and dispersal. We emphasize that there is no one correct method and encourage researchers planning studies to carefully consider the data requirements to best address questions of interest."
Mola expanded on the topic on his website: "This manuscript contains more within it than the title alone lets on. Understanding the landscape-scale movements of bumble bees has long-plagued researchers despite heavy interest. In some ways reviewing the methods is to review the history of bumble bee movement research. We cover the tools one may use for tracking bumble bees. We also include information on how to interpret and contextualize results, considerations on conceptualizing bumble bee movement, and suggestions for future research efforts. I think folks will find the table and supplemental information particularly handy in planning research and writing manuscripts (we provide a long list of great studies on bumble bee movement in the supplemental). If you're really interested in the research area, consider coming to BOMBUSS 2.0 where Jamie Strange and I will be co-leading a session on this very topic. https://wildlifepreservation.ca/about-bombuss/"
In 2018, Mola wowed the judges at the graduate student research poster competition at the fourth annual UC Davis Bee Symposium for his work on "Bumble Bee Movement and Landscape Genetics." As the first-place winner, he received the $850 cash prize. The judges: Tom Seeley, professor at Cornell University, the symposium's keynote speaker; speaker Santiago Ramirez, assistant professor of evolution and ecology at UC Davis, and native pollinator specialist Robbin Thorp (1933-2019), distinguished emeritus professor at UC Davis.
“In conservation biology and ecological study, we must know the distances organisms travel and the scales over which they go about their lives,” Mola said of his work at the time. “To properly conserve species, we have to know how much land they need, how close those habitats need to be to each other, and the impact of travel on species success. For instance, if I'm told there's free burritos in the break room, I'm all over it. If the 'free' burritos require me traveling to Scotland, it's not worth it and I would spend more energy (and money) than I would gain. For pollinators, it's especially important we understand their movement since the distances they travel also dictates the quality of the pollination service they provide to crop and wild plants."
“Despite this importance, we know comparatively little about the movements of bees--the most efficient of pollinators--due to the difficulty of tracking individuals," Mola explained.
Mola says that "Unlike birds or large mammals, we can't just attach large radio collars and follow them around. As such, my work has focused on improving methods that we can use for study. I use a combination of landscape ecology and molecular genetics to identify the locations of siblings (colony-mates) in landscapes. From that information, we can infer all sorts of useful information about the potential foraging range, habitat use, population size, etc. It's a very exciting time to be working on these topics as the availability of new genetic and GPS technologies allows us to answer or re-address scientific and conservation issues with bees.”
Mola's next step: Fort Collins, Colo., where he will be a USGS (U.S. Geological Survey) Mendenhall postdoctoral fellow.
- Author: Kathy Keatley Garvey
The blood-sucking insect, which transmits the parasite that causes human and animal trypanosomiasis, has wreaked havoc in African countries.
It's distinguished from other Diptera by unique adaptations, "including lactation and the birthing of live young," says medical entomologist-geneticist Geoffrey Attardo, assistant professor, UC Davis Department of Entomology and Nematology.
Mark your calendar.
The UC Davis Department of Animal Science is hosting his seminar, “Tsetse Fly Reproduction: Exploration of the Unique Reproductive Adaptations of a Neglected Disease Vector” at 12:10 p.m., Monday, Oct. 7 in the Weir Room, 2154 Meyer Hall.
"Tsetse flies function as the sole vectors of human and animal Trypanosomiasis in sub-Saharan Africa," Attardo says in his abstract. "In addition to their role as disease vectors, tsetse flies distinguish themselves from other flies in terms of their amazing physiological adaptations. Of these adaptations, the reproductive biology/physiology of these flies stands out as one of the most dramatic."
"Female tsetse flies carry their young in an adapted uterus for the entirety of their immature development and provide their complete nutritional requirements via the synthesis and secretion of a milk like substance. Tsetse milk is derived of roughly 50 percent lipids and 50 percent proteins. Tsetse milk proteins are coded for by repurposed genes and by genes specific to tsetse flies. These genes are regulated in tight correlation with the female's pregnancy cycle. In addition, tsetse flies have established an obligate relationship with the bacterial symbiont Wigglesworthia glossinidius. This symbiont is required for lactation and larval development. Metabolic analysis of tsetse flies lacking this symbiont reveals a tightly integrated relationship between these organisms. This relationship is required for the metabolism of blood, production of essential micronutrients and synthesis/secretion of lipids essential for milk production.”
Attardo led landmark research published Sept. 2 in the journal Genome Biology that provides new insight into the genomics of the tsetse fly. The researchers compared and analyzed the genomes of six species of tsetse flies. Their research could lead to better insights into disease prevention and control.
“It was a behemoth project, spanning six to seven years,” said Attardo. “This project represents the combined efforts of a consortium of 56 researchers throughout the United States, Europe, Africa and China.” (See news story.)
In 1995, the World Health Organization (WHO) estimated that 60 million people were at risk of sleeping sickness, with an estimated 300,000 new cases per year in Africa, and fewer than 30,000 cases diagnosed and treated. Due to increased control, only 3796 cases were reported in 2014, with less than 15,000 estimated cases, according to WHO statistics.
WHO says that the parasitic disease “mostly affects poor populations living in remote rural areas of Africa. Untreated, it is usually fatal. Travelers also risk becoming infected if they venture through regions where the insect is common. Generally, the disease is not found in urban areas, although cases have been reported in suburban areas of big cities in some disease endemic countries.”
- Author: Kathy Keatley Garvey
Schroeder will speak on "Endless Worms Most Beautiful" at 4:10 p.m. in Room 122 of Briggs Hall, off Kleiber Hall Drive. Plant nematologist and assistant professor Shahid Saddique of the Department of Entomology and Nematology will serve as the host. The event is open to all interested persons.
Schroeder's website indicates that he "makes new discoveries on the biology of nematodes, one of the world's most abundant group of animals. His work identifies how nematodes survive difficult environmental conditions, which helps control parasitic nematodes and reveals how higher animals like humans deal with stress."
"My laboratory studies the development and anatomy of diverse nematode species to understand the plasticity of structure within species and the generation of novel forms across evolution," Schroeder explains in his abstract. "Caenorhabditis elegans is a bacterial feeding nematode widely used as a model for understanding basic cellular and molecular processes. Under specific environmental stressors, C. elegans can enter a developmental switch into a stress-resistant dauer stage. During the entry to dauer, several tissues rapidly remodel. We discovered a new neuronal remodeling phenotype during dauer formation and have described several mechanisms controlling this phenotype."
"In addition to neuronal remodeling," he says, "C. elegans also undergoes remodeling of epithelial stem cell-like 'seam cells.' We have identified a group of extracellular proteins that regular the seam cell remodeling process. While C. elegants research is blessed with numerous tools, this nematode represents only one of thousands of species inhabiting wide-ranging aquatic and terrestrial habitats. Together with their relatively simple anatomy, nematodes are an ideal taxon to understand the evolution of anatomy."
Schroeder adds: "In addition to our work in C. elegans, we are exploring the mechanisms controlling new anatomical forms. For example, we recently found that the seam cell homologs in the cyst nematode Heterodera glycines have increased proliferative capacity compared with C. elegans. This increased cell division likely contributes to the atypical lemon-shape of H. glycines. Finally, we are beginning a collaboration with the NIH-funded WormAtlas to expand their offerings beyond C. elegans and help bridge the divide between the sometimes-disparate research communities."
Schroeder, who joined the Department of Crop Sciences in 2013, received his bachelor of science degree in chemistry from Earlham College, Richmond, Ind., in 1998, and his doctorate in plant pathology from the University of Wisconsin-Madison in 2008. He then served as a postdoctoral fellow in the Department of Genetics, Rutgers University, New Jersey, from 2008 to 2013.
Community ecologist and assistant professor Rachel Vannette is coordinating the seminars, which are held every Wednesday at 4:10 p.m. in 122 Briggs Hall. (See schedule.)
