Then you'll want to attend--or listen via Zoom--the next seminar hosted by the UC Davis Department of Entomology and Nematology.
Nissa Coit, a master's graduate student in the laboratory of Extension apiculturist Elina Niño, UC Davis Department of Entomology and Nematology, will present her exit seminar on "Effects of Ethyl Oleate Pheromone on Honey Bee (Apis mellifera)" at 4:10 p.m., Wednesday, Sept. 28.
She will deliver her seminar in Room 122 of Briggs Hall, UC Davis campus, and virtually on Zoom. The link:
"In winter, honey bees undergo a transition to a diutinus state, during which time brood rearing declines or stops entirely, and worker bees live for up to 20 weeks," Coit says in her abstract. "The mechanism, causes, and geographic prevalence of this transition are unknown, and can make managing honey bees in certain regions challenging. We hypothesized that the transition to overwintering is regulated by the forager pheromone, ethyl oleate, when forager bees are relegated to the hive for longer periods of time during poor weather conditions. We exposed bees of different ages and tasks to ethyl oleate and measured accepted markers of overwintering. Our findings indicate ethyl oleate may affect the efficiency of metabolism of protein into fat stores, allowing young bees to prepare for suboptimal conditions. Ethyl oleate, when concomitant with other factors such as gradual decline in brood pheromone, pollen dearth, cold temperatures, and photoperiod, may contribute to the transition to overwintering."
She received her master's degree from UC Davis on Sept. 9, and is currently working and living in Vermont. "I work at Sterling College, where I am teaching entomology, ecology, biology, and apiculture in the undergraduate program, as well as developing course materials for the continuing education department in a variety of subjects such as water management, agroecology, pest management, and sustainable agriculture and food systems."
Her biography on the Niño website includes: "She was founder and president of the Carolina Beekeeping Club, whose efforts recently succeeded in making UNC, a Bee Campus USA. She first became interested in honey bees in high school while taking a summer class at Cornell. In college, she began volunteering at the NC State University Honey Bee Research Laboratory to gain more experience with bees. Since then, she has also worked at NC State as a research technician and conducted her own research on pheromone variation of brood and queens among different stocks of bees."
Coit studied abroad at the University of Otago, Dunedin, New Zealand, in 2017, from July to November.
Emily Meineke, assistant professor of urban landscape entomology, UC Davis Department of Entomology and Nematology, coordinates the department's seminars for the 2022-23 academic year. All 11 seminars will take place both person and virtually at 4:10 p.m. on Wednesdays in Room 122 of Briggs Hall except for the Nov. 9th and Dec. 7th seminars, which will be virtual only, she said. (See list of seminars)
For further information on the seminars or technical difficulties with Zoom, contact Meineke at email@example.com.
Shapiro, a 50-year member of the UC Davis faculty, says that "Although it is a significant alfalfa pest, this butterfly overwinters as a larva almost entirely in annual vetch at low altitudes, and colonizes alfalfa only as the vetch senesces in May-June. Aside from alfalfa and annual vetches, it also breeds on a variety of clovers and sweet clovers and occasionally on lupines."
We know that European colonists introduced honey bees (Apis mellifera) into the Jamestown colony (now Virginia) in 1622.
But where did the Western honey bee originate? Scientists at York University, a public research university in Toronto, Ontario, Canada, recently discovered that it originated in Asia. Genetics told them so.
The abstract of the paper, "Thrice Out of Asia and the Adaptive Radiation of the Western Honey Bee," published in Science:
"The origin of the western honey bee Apis mellifera has been intensely debated. Addressing this knowledge gap is essential for understanding the evolution and genetics of one of the world's most important pollinators. By analyzing 251 genomes from 18 native subspecies, we found support for an Asian origin of honey bees with at least three expansions leading to African and European lineages. The adaptive radiation of honey bees involved selection on a few genomic 'hotspots.' We found 145 genes with independent signatures of selection across all bee lineages, and these genes were highly associated with worker traits. Our results indicate that a core set of genes associated with worker and colony traits facilitated the adaptive radiation of honey bees across their vast distribution."
York University doctoral student Kathleen Dogantzis of the Faculty of Science led the research team. "Our research suggests that a core-set of genes allowed the honey bee to adapt to a diverse set of environmental conditions across its native range by regulating worker and colony behaviour," Dogantzis says in a Phys.Org article.
Why is it important to know the origin? To understand its evolution, its genetics and its adaptation and how this can relate to the current population of bees and to modern-day beekeeping.
Or, as they wrote in their scientific paper: "Resolving the ancestral origin and evolutionary expansion of A. mellifera will enhance our ability to identify derived and ancestral genetic mutations. This is especially relevant for tracing the evolution of derived phenotypes and for discerning how locally adapted subspecies may contribute to the fitness and diversity of managed colonies."
"In conclusion," they wrote, "we have presented compelling evidence that A. mellifera emerged in Asia with the remainder of extant honey bees but then expanded into its current distribution via Western Asia. This expansion event is marked by at least three independent colonization routes that gave rise to seven genetically distinct lineages. Modern populations of A. mellifera maintain high genetic diversity, which has allowed the species to adapt to diverse environments through repeated selection among a common set of genes. These genes are often related to worker phenotypes, supporting that the worker caste is key to the adaptative radiation of the species."
Jamestown Colony. The first honey bees to arrive in what is now the United States were what beekeepers call the "dark bee" subspecies of Northern Europe, Apis mellifera mellifera. Today the Italian bee, Apis mellifera ligustica is the most common bee the United States.
The Italian bee didn't arrive in America until 1859. "The American beekeeping public was enamored with the newly available yellow and gentle bees," bee breeder-geneticist and co-author Susan Cobey of Washington State University (formerly of UC Davis) wrote in a chapter of the book, Honey Bee Colony Health: Challenges and Sustainable Solutions. "As a result, Italian-type bees form the basis for most present-day commercial beekeeping stocks in the U.S. Following the arrival and success of honey bees from Italy, U.S. beekeepers developed an interest to try other honey bee subspecies." Cobey studied with Harry H. Laidlaw Jr. (1907-2003) of UC Davis, the "father of honey bee genetics" and for whom the university's bee biology facility is named.
And speaking of the introduction of honey bees into the United States, it took 231 for years for honey bees to arrive in California. Beekeeper Christopher A. Shelton introduced honey bees to the Golden State in 1853, establishing an apiary just north of San Jose. (Check out the bee plaque at the San Jose International Airport.)
Now we know that our beloved Western honey bee originated in Asia.
So, here you are, a honey bee nectaring on a Mexican sunflower, Tithonia rotundifola.
All's right with the world, at least in your world. You're sipping nectar to take home to your colony and suddenly...a buzz.
A male long-horned bee, probably Melissodes agilis, is trying to dislodge you from your flower.
You hold your ground (your flower) but you let him know that his presence is unwanted. You lift a foreleg in your defense to block him.
The long-horned bee flies off, and you continue to nectar. All's right with the world. (Until your next encounter with a fast-moving, highly territorial male long-horned bee bent on dislodging you from your flower.)
The late Robbin Thorp (1933-2019), distinguished emeritus professor of entomology at UC Davis, used to say that these male long-horned bees target any critter residing on "their" flowers. It could be a honey bee, a bumble bee, a carpenter bee, a syrphid fly, a butterfly or a beetle. Or something else. They want to save the flowers for their own species and then mate with them, he said.
Just a day in the life of a non-native honey bee, Apis mellifera, and a native long-horned bee, Melissodes agilis.
At a recent visit to the UC Davis Ecological Garden at the Student Farm, we watched a honey bee, Apis mellifera, and a lygus bug nymph, Lygus hesperus, foraging on a batchelor button, Centaurea cyanus.
The bee: the beneficial insect.
The lygus bug or Western tarnished plant bug: a pest.
The lygus bug, which punctures plant tissues with its piercing mouthparts, was there first, but no matter. The bee joined in, edging closer and closer until they touched.
In photography insect circles, that's a "two-for"--two insects in one image.
The bee finally buzzed off, leaving the lygus bug to "dine" alone.
The lygus bug, distinguished by a conspicuous triangle on its back, is a very serious pest of cotton, strawberries and seed crops, including alfalfa. Scientists estimate that in California alone, the pest causes $30 million in damage to cotton plants each year, and at least $40 million in losses to the state's strawberry industry. The insect is also a pest of numerous fruits and vegetables, including apples, pears, peaches, eggplant, tomato, potato, artichoke, lettuce, sugarbeet, and beans. See what the UC Statewide Integrated Pest Management Program (UC IPM), says about the pest.
What do they look like? "Adult lygus bugs are green, straw yellow, or brown with a conspicuous yellow or pale green triangle on their backs," UC IPM says. "Nymphs are light green...Lygus can move into gardens or orchards from weeds, especially when they dry up. They are a particular problem in beans, strawberries, and orchard crops, feeding on developing flower buds and fruit. Fruit may become blemished and discolored, deformed, or twisted and may develop depressions or pustules."
Cotton? "Lygus bugs," says UC IPM, "migrate to cotton from other hosts, so management of this pest begins with assessing its populations outside the field. Check for them on weeds, in nearby alfalfa, and in other crops, and keep in touch with your pest control adviser, Extension agent or Farm Advisor for area-wide information on lygus bug populations. Proper management of alfalfa harvest can reduce damaging migrations to cotton."
Cooperative Extension specialist Ian Grettenberger, UC Davis Department of Entomology and Nematology, works closely with farmers in their lygus bug battles.