- Author: Kathy Keatley Garvey
The top honors went to:
- Doctoral candidate Shawn Christensen and doctoral student Alexia "Lexie" Martin, both of the lab of associate professor and community ecologist Rachel Vannette, vice chair of the department; and
- Doctoral student Iris Quayle of the lab of professor and arachnologist Jason Bond, the Evert and Marion Schlinger Endowed Chair and associate dean, College of Agricultural and Environmental Sciences.
Christensen competed in the Plant-Insect Ecosystems (P-IE) Section, Apiculture; Martin in the P-IE Section, Pollinator Biology; and Quayle in the Systematics, Evolution, and Biodiversity (SysEB) Section, Biogeography.
Shawn Christensen. Christensen presented "Bee Specific! Solitary Bee (Anthophora bomboides) Hosts a Specialized Core Microbiome through Development."
His abstract: "Host-microbe interactions are important for the development and fitness of many macroorganisms. While social bees are dependent on a vertically transmitted gut microbiome, solitary bees, which comprise the vast majority of species diversity within bees, lack a specialized gut community. We explored the microbiome associated with the complete life cycle of the ground-nesting polylectic solitary bee Anthophora bomboides standfordiana, including bacterial and fungal composition and abundance. In contrast to expectations, we found that immature stages of this solitary bee maintain a distinct core microbiome consisting of Actinobacteria and one yeast species. Stage-specific shifts in microbial abundance and community composition occur most notably during bee diapause, during which the abundance of bacteria and fungi increased dramatically. We tested two adaptive hypotheses regarding the role of the microbiome in bee ecology. First, isolated brood cell Streptomyces strains were found to inhibit growth of multiple often pathogenic filamentous fungi, suggesting a role in pathogen protection during the long period of diapause. Second, sugar alcohol composition changed in tandem with major changes in microbial abundance suggesting links with bee metabolism or overwintering biology. Our results suggest that this Anthophora species hosts a conserved core microbiome that may provide key fitness advantages through larval development and overwintering. Much work remains to examine the nature of bee-microbiome ecology, but our study reframes the conditions thought to promote the evolution and maintenance of symbiosis."
Co-authors: Rachel Vannette and Sriram Srinivas, UC Davis; Quinn McFrederick, UC Riverside; Bryan Danworth, Cornell University; and Stephen Buchmann, University of Arizona
Her abstract: "Bees interact with and in some cases benefit from a diverse community of microbes, which can be obtained through intraspecific interactions or the environment. Due to differences in sociality, bee species vary in their main route of microbial acquisition and their dependence on microbes. Despite the observation that intraspecific transmission of microbes is imperfect and environmental microbes are nearly ubiquitous in flowers, the potential impacts of intraspecific versus floral microbes on overall pollinator health have not been evaluated. This study uses two model bee species - one social (Bombus impatiens) and one solitary (Osmia lignaria)--to assess the establishment and health impacts of floral and intraspecific microbes. 2x2 factorial experiments were performed on B. impatiens microcolonies and O. lignaria females to selectively introduce intraspecific microbes and/or floral microbes. Survivorship and reproduction were measured to assess bee health and fitness, and DNA extractions and amplicon sequencing were performed on bee guts to evaluate microbial establishment. The results of this study will inform how microbes from different acquisition routes establish in the host, shape the gut microbiome, and affect host health. Since many macroorganisms encounter both intraspecific and environmental microbes, this study provides a framework for similar work in other organisms."
Co-author: Rachel Vannette, UC Davis
Her abstract: "In the Namib Desert, one of the largest and oldest deserts, the genus Onymacris contains a rarity for darkling beetles (Tenebrionidae) – the presence of eight species with striking ‘white' elytra (ranging from stark white to tan/striped). This study seeks to examine the phylogenetic relationships among white Onymacris species to test whether multiple derivations of white elytra is due to convergence or introgression. Population genomic data (3RAD) was generated from all white species of Onymacris with intraspecific sampling for four widespread species (O. marginipennis, O. bicolor, O. candidipennis, O. langi cornelii). Phylogenetic trees were inferred from 995 loci using concatenated and coalescent-based methods. The analyses supported two clades: langi and bicolor each of which contain species with pure white elytra. Variational autoencoder (VAE) clustering analysis shows a pattern of genetically isolated populations (bicolor) and gene flow indicating introgression (langi). These analyses also infer a potential new Angolan species sister to O. marginipennis in need of evaluation. Ancestral character state and biogeographic reconstruction resolve the timing of white species' color expression against the backdrop of sand sea emergence and increased aridity in the Namib, a landscape renown for ‘pocket speciation' and an impressive amount of darkling beetle diversity accounting for nearly 80% of the known endemic beetle fauna. Dynamic coloration provides a fascinating system through which to examine the role of ecological pressures and evolutionary mechanisms but requires a phylogenetic framework to understand organisms' potential adaptations to extreme environments, which is increasingly vital in the face of global trends aridity trends."
Co-authors: Lisa Chamberland, James Starrett and Jason Bond, UC Davis
The full list of student winners--first, second and third places--is here.
Founded in 1889, ESA is the largest entomological organization in the world. Its more than 7,000 members are affiliated with educational institutions, health agencies, private industry, and government.
- Author: Kathy Keatley Garvey
Bob stole the show.
Picture this: UC Davis forensic entomologist Robert “Bob” Kimsey is portraying “Dr. Death” inside Briggs Hall during the 109th annual UC Davis Picnic Day, but just outside the building, another Bob is grabbing the spotlight.
That would be Bob, a two-inch long American cockroach, Periplaneta americana, competing in the Roach Races.
"Roach Bob" is part of the colony that "Dr. Bob" inherited from the late entomology emeritus professor Charles Judson (1926-2015).
Every year someone names a roach “Bob” to honor the colony keeper.
The reddish-brown roaches race inside a tubelike track. An air pump, emitting "a gentle breeze," encourages them to leave the starting gate and head for the finish line--all six legs flying.
This year Bob, Speedster and Charlie proved to be crowd favorites.
“We rotate the roaches so they don't get too stressed from the heat, but Speedster definitely lived up to its name,” said Roach Race coordinator Taylor Kelly, a doctoral candidate in the lab of medical entomologist/geneticist Geoffrey Attardo, associate professor, UC Davis Department of Entomology and Nematology.
“Bob was a definite winner,” said race announcer-roach handler Iris Quayle, a first-year doctoral student in the lab of Jason Bond, the Evert and Marion Schlinger Endowed Chair in the UC Davis Department of Entomology and Nematology and associate dean, UC Davis College of Agricultural and Environmental Sciences. “I don't think the crowd knew they were naming a cockroach after Bob Kimsey but it worked out well. And the aptly named Speedster gave everyone a run for their money!”
Kimsey's wife, Lynn Kimsey, a UC Davis distinguished professor and director of the Bohart Museum of Entomology, also is honored annually with a roach named “Lynn.” Last year her namesake won a few races; this year, no.
“We had audience members be our Roach Coaches--they encouraged the roaches to run with a gentle breeze of air,” Taylor said. “Later on in the day, we had a very speedy roach named Charlie that clinched 4 rounds back-to-back. Charlie was named by a youngster participating as his Roach Coach. He named the cockroach after his little brother.”
“At the beginning of the day we had some near-escapees and definitely elicited some screams from the crowd when one managed to get free,” Iris said, “but Taylor and I were too fast and were able to get them all back into the colony in the end. We also had some stubborn racers who didn't want to leave their racing tube after the competition.”
Some spectators asked Iris what the experience was like. “I did get a few questions about if I was okay holding them, and if I was scared I would get sick, but once I explained that this was a maintained colony by the college and that cockroaches are only as dirty as their environment, people came around and were even willing to give the racers a little head pat for good luck.”
In between races, the announcers asked if anyone wanted to pet a cockroach. They did, and took cell phone images and videos, too. “It was fun to let folks give the roaches a little head pat, a lot of folks said they seemed more cute after getting up close and personal,” Kelly said. “I hope folks loved roaches a little more after the races!”
Did anyone ask to take one home? “No, but we had many people complain that they already had too many lurking at home,” Taylor quipped.
Taylor was a member of the 2022 UC Davis Entomology Games team that won the national championship at the Entomological Society of America meeting. She also won the 2022 Student Leadership Award from the Pacific Branch, Entomological Society of America (PBESA) for her leadership in STEM and entomological activities.
Iris recently won first place in the doctoral student research competition at the 2023 PBESA meeting, held in Seattle. Her presentation, “Colorless but Never Dull: Unraveling Population Genetics and Color Evolution in ‘White' Darkling Beetles (Onymacris),” was her first-ever scientific presentation. Iris served a year as a National Science Foundation Research Experience for Post-Baccalaureate Students (NSF-REPS) in the Bond lab before being accepted into the doctoral program in 2022.
Kimsey, an associate adjunct professor and lecturer since 1990, has served as the master advisor for the animal biology (ABI) major since 2010 and an ABI lecturer since 2001. He also serves as the UC Davis Entomology Club advisor. He annually co-chairs the UC Davis Department of Entomology and Nematology's Picnic Day activities with a member of the Entomology Graduate Student Association (EGSA). This year he co-chaired the event with doctoral student Grace Horne of the lab of urban landscape entomologist Emily Meineke.
- Author: Kathy Keatley Garvey
But when she began delivering her first-ever presentation at a scientific conference, “I found it quite fun to present my work and see people's excitement.”
Quayle, a first-year doctoral student in the Jason Bond lab, UC Davis Department of Entomology and Nematology, went on to win first place in the doctoral student competition at the annual meeting of the Pacific Branch, Entomological Society of America (PBESA), held recently in Seattle. The organization encompasses 11 Western states, plus Canada, Mexico and U.S. territories.
Quayle discussed her research, “Colorless but Never Dull: Unraveling Population Genetics and Color Evolution in ‘White' Darkling Beetles (Onymacris).”
“It was a really great conference with a lot of interesting talks,” Quayle said, “so I feel very honored to have placed first in the Ph.D student competition.”
“Iris has hit the ground running in all respects," said Bond, the Evert and Marion Schlinger Endowed Chair in Insect Systematics, Department of Entomology and Nematology, and associate dean, College of Agricultural and Environmental Sciences. "Winning the student paper award, the first time ever presenting her research, reflects her exceptional capabilities as a scientist and as a future professor and teacher. Iris comes from a non-traditional STEM background and it is exactly those experiences that will continue to contribute to her success as she evolves as a scientist. I predict that this is only a prelude of things to come.”
Quayle is focusing her dissertation on the evolutionary relationships and color/trait evolution in Onymacris. “This genus displays a lot of phenotypically and behaviorally charismatic traits and I am excited for my dissertation research to expand and grow in the next few years,” she said.
In her talk, Quayle noted that Tenebrionidae (darkling beetles) comprise “more than 80 percent of all known beetle species in the Namib, where the genus Onymacris contains a rarity unexpected from aptly named darkling beetles--the presence of several species with striking ‘white' elytra (wing sheaths).”
“A known history of hybridization, strong inclination towards polytypic taxa, and paraphyletic status with another genus reveals that coloration and speciation in Onymacris is anything but straightforward,” said Quayle, who is examining “the phylogenetic relationships between white Onymacris species to determine whether multiple derivations of pure white elytra is due to convergence or introgression.”
In her population genomic analysis, Quayle extracted DNA from all white Onymacris, using additional specimens for the four species with the largest geographical ranges (O. marginipennis, O. bicolor, O. candidipennis, O. langi cornelii).
“Studying the population structure and genomic components leading to white coloration highlights behavioral and ecological adaptations of organisms to an arid environment which is increasingly vital in the face of global trends towards aridity,” she told the group.
Quayle fielded several questions about the potential ecological pressures that may be driving diverse coloration. She noted that the darkest of white species (O. marginipennis which is brown and striped) is found primarily on vegetated hummocks, while all white species (O. candidipennis and O. bicolor) are found only on sandy coastal dunes with no vegetation.
Quayle served a year as a National Science Foundation Research Experience for Post-Baccalaureate Students (NSF-REPS) in the Bond lab before being accepted into the doctoral program in 2022. “I'm so grateful that I've been able to start this work early in my first year as a Ph.D. student,” she said.
Quayle, who grew up in Paradise, Calif., holds an associate of science degree in biology from Sacramento City College. Formerly known as Iris Bright, she received her bachelor of fine arts degree (creative writing and literature) in the honors program from Emerson College, Boston, Mass., in 2015 before switching to science. Fascinated with insects in her early childhood, she began collecting specimens at age 7. Her grandfather was an amateur entomologist.
Her career plans? Becoming a professor “so I can do further research and also share my passion and interests with the next generations!”
- Author: Kathy Keatley Garvey
"I just got bit by a brown recluse spider in California."
No, you didn't--unless you recently returned from a state where they are established or handled one shipped from that area. There are no established populations of Loxoceles reclusa in California.
So said doctoral candidates Emma Jochim and Xavier Zahnle of the Jason Bond arachnology lab when they dispelled myths in their 30-minute, family friendly session about arachnids at the Bohart Museum of Entomology open house, "Many Legged-Wonders," on Saturday, March 18. First-year doctoral student Iris Quayle of the Bond lab moderated the session. Their major professor, Jason Bond, is the Evert and Marion Schlinger Endowed Chair in Insect Systematics, UC Davis Department of Entomology and Nematology, and associate dean, College of Agricultural and Environmental Sciences.
Jochim and Zahnle covered scores of myths. Here are their answers (abbreviated and shared here by Iris Quayle)
Myth: Arachnids and myriapods are insects.
Answer: No, they're not insects. You can tell them apart by the number of body segments and legs. Arachnids have two body segments and 4 pairs of legs. Insects have 3 body segments and 3 pairs of legs, and myriapods have lots of body segments with either one or two pairs of legs per segment.
Myth: Millipedes have 1000 legs and centipedes have 100 legs.
Answer: Only one recently (2021) species of millipedes has 1000 legs, actually 1300 plus, and that is Eumillipes persephone from Australia. Many soil centipedes have more than 100 legs.
Myth: Camel spiders can jump 4 to 6 feet straight up and eat the stomachs of camels.
Answer: Most solifugid species are 2-3 inches in length and definitely cannot bite into hard camel hide. They can have a bit of a bite for humans, but have no venom, though.
Myth: These are all daddy long legs (image shown of a harvester, crane fly, and cellar spider).
Answer: This depends on where you are from regionally. They all are referred to as "daddy long legs." Also, the myth of daddy long legs being super venomous is false as being dangerous to humans. Of this group, only the Pholcids (cellar spiders) have venom. The venom of cellar spiders can kill insects but is too weak to bother humans; their venom composition is very weak.
Myth: Black widows get their name because females always cannibalize males after mating.
Answer: That is why they got their name, but they are not the only spiders who do this. It is actually quite common fpr a a male to offer a nuptial gift in the form of a fly or other food source to deter the female from devouring him.
Myth: This creature (image of an amblypygid shown) exists only in the fictional world of Harry Potter.
Answer: Amblypygids are very real and are arachnids, but not spiders.
Myth: You consume eight spiders in your sleep every year.
Answer: It's highly unlikely that you will ever consume any in your sleep.
Myth: Every tick will give you a deadly disease
Answer: Ticks are vectors for lots of diseases. Here in California only the blacklegged tick carries Lyme disease.
Myth: Baby scorpions are deadlier than adults.
Answer: No, they do not produce enough to be deadly.
Myth: Both millipedes and centipedes bite.
Answer: Only centipedes bite and they are venomous.
Statements for the Audience: True or false?
The audience was invited to call out the answers.
Statement: There are spiders that can spit silk out of their mouth.
Answer: True. The family Scytodidae spit silk as well as produce silk though their spinnerets. Used for mating and prey capture.
Statement: Maternal care can be seen in some arachnids and myriapods.
Answer: True. Many arachnids carry their young on their backs, and myriapods will protect their egg clutch.
Statement: The grasshopper mouse is immune to scorpion venom.
Answer: True. Bark scorpions comprise the majority of its diet.
Statement: Some myriapods and all scorpions fluoresce.
Answer: True, main theories for scorpions are that they use this to communicate in the dark or to warn of predators. Main theory for myriapods is that it is to warn of predators. Some myriapods are eyeless (blind).
Bohart Open House. The Bohart Museum open house, held from 1 to 4 p.m., featured displays of arachnids. Visitors conversed with the scientists and held Madagascar hissing cockroaches and walking sticks from the Bohart's live petting zoo. Directed by UC Davis distinguished professor Lynn Kimsey, the Bohart Museum houses a global collection of eight million insect specimens, plus the petting zoo and a gift shop. Located in Room 1124 of the Academic Surge Building, 455 Crocker Lane, UC Davis campus, it is open to the public Mondays through Thursdays, from 8 a.m. to noon, and 1 to 5 p.m. More information is available on the Bohart website at https://bohart.ucdavis.edu or by emailing bmuseum@ucdavis.edu.
Resources on brown recluse spiders (Rick Vetter, UC Riverside)
- How to Identify and Misidentify a Brown Recluse Spider
- Myth of the Brown Recluse: Fact, Fear, and Loathing
- Recluse Spider Map