Four UC Davis doctoral students stood in the coveted "presidential circle" at the Entomological Society of America (ESA) conference, receiving awards for their research presentations ranging from ants and soil microarthropods to blue orchard bees and orchid bees.
The 74th annual conference, themed "Connect Your Science, Expand Your Net." took place Nov. 8-11 in Columbus, Ohio.
At the annual President's Prize competition, graduate students seeking to share their work can choose to either present a 10-minute oral presentation or a poster display. Those winning first place, or the President's Prize, received a free ESA membership for the upcoming year, a $75 gift card, and a certificate. The second-place award is a free ESA membership for the upcoming year and a certificate.
Congratulations to the four:
Luke Doyle, a first-year doctoral student inthe lab of ant specialist Rodolfo da Silva Probst, assistant professor of insect biology, UC Davis Department of Entomology and Nematology (ENT-NEM), College of Agricultural and Environmental Sciences, won a first-place award or the President's Prize, for his 10-minute research presentation on "Subtle Surprises and Shared Akaloids in Ohio Aphaenogaster Ants." A recent graduate of Ohio State University, he competed in the category, Systematics, Evolution and Biodiversity.
Sabrina Ott, a second-year doctoral student in the lab of nematologist Amanda Hodson, assistant professor of soil ecology and pest management, (ENT-NEM), won a President's Prize for her research poster, "The Effects of Agricultural Management and Earthworm Additions on Soil Microarthropod Communities in a California Almond Orchard." She competed in the Systematics, Evolution and Biodiversity category; subcategory, Biodiversity and Behavior.
Alexia "Lexie" Martin, doctoral candidate in the lab of community ecologist Rachel Vannette, professor and vice chair of ENT-NEM, won second place for her 10-minute research presentation, "Non-Native Horn-face Bees (Osmia cornifrons) as Possible Disease Reservoirs for Native Blue Orchard Bees (Osmia lignaria). She competed in the Plant-Insect Ecosystems category; subcategory, Ecology and Conservation.
Marissa Sandoval, doctoral candidate in the lab of evolutionary biologist and orchid bee specialist Santiago Ramirez, Department of Evolution and Ecology, College of Biological Sciences, won a President's Prize for her 10-minute research presentation on "Floral Fragrance to Mate Attraction: Investigating the Chemical Ecology of a Euglossine Bee Alongside its Obligate Orchid." She competed in the Plant-Insect Ecosystems category; subcategory, Pollinators and Pollination.
Their abstracts:
Luke Doyle's Abstract
"Alkaloids are a diverse class of heterocyclic nitrogenous compounds found in many organisms, including ants (Hymenoptera: Formicidae), who use them in defense and communication. While several Aphaenogaster Mayr, 1853 ant species are known to have alkaloids, the diversity and species-specificity of these compounds in the genus remains poorly characterized, a knowledge gap compounded by the presence of species complexes within the genus. We investigated alkaloid presence and diversity by examining head and gaster extracts collected from five described Aphaenogaster species and two cryptic lineages within the Aphaenogaster rudis Wesson & Wesson, 1940 complex at ten sites in Ohio, USA. Chemical profiles were characterized using gas chromatography-mass spectrometry, and cytochrome c oxidase subunit 1 sequences were generated to confirm morphological identifications. We found that alkaloid presence is conserved across different Aphaenogaster species, but relative abundance of individual alkaloids varies between species, especially those with differing natural histories. We also discovered four frequently occurring alkaloids not previously reported in Aphaenogaster: 2,5-dimethyl-3-ethylpyrazine, cotinine, methyl nicotinate, and trimethylpyrazine. Lastly, we provide genetic evidence of sympatry between cryptic clades within the A. rudis and A. picea (Wheeler, 1908) species complexes. This work improves our understanding of alkaloids in Aphaenogaster and provides a basis for future work examining the roles of natural history, niche differentiation, and speciation in the chemical evolution of this taxonomically complex ant genus."
Sabrina Ott's Abstract
"Soil microarthropods, primarily mites (Acari) and springtails (Collembola), comprise a large proportion of soil biodiversity and contribute to decomposition, nutrient cycling, and carbon sequestration. Despite their ecological importance, soil microarthropods remain poorly studied in California agricultural systems. Non-native earthworms are often the dominant soil macrofauna in agricultural systems, altering soil structure and accelerating decomposition and denitrification, so their effects on soil microarthropods should be considered alongside management practices. We investigated the effects of plant cover type, compost application, and earthworm additions on soil microarthropod communities in 36 1m² plots within an almond orchard in Davis, California. Soil was sampled in January 2026 before treatment establishment and again in March following compost and earthworm additions. Microarthropods were extracted from 400-mL soil samples using Galen–Berlese funnels. We identified 54 families across six taxonomic groups: Oribatida, Sarcoptiformes, Trombidiformes, Mesostigmata, Collembola, and 'Other' (Myriapoda, Diplura, and Protura). Plant cover type was the strongest correlate of taxonomic group abundance, whereas compost and earthworm additions showed no significant effects during the study period. Dunn’s pairwise comparisons revealed significant differences among cover types for Oribatida, Sarcoptiformes, Collembola, Mesostigmata, and “Other' (adjusted P < 0.05). Differences were associated with grass cover for Oribatida, resident vegetation for Collembola, Mesostigmata, and 'Other,' and bare ground for Sarcoptiformes. These preliminary findings suggest that vegetation cover may be an important driver of soil microarthropod communities in agricultural systems, highlighting the potential of cover crop management to support belowground biodiversity."
Lexie Martin's Abstract
"Pathogen infection is one of the main contributors to bee decline across many species. In addition to bees becoming infected by diseases from conspecifics, they are also at risk of pathogen spillover (the movement of a pathogen from one bee species to another) due to shared use of nesting resources (i.e. mud, leaves) and flowers. Because pathogens are capable of evolving quickly to overcome host defenses, pathogens from non-native bees may be especially virulent in native bees who have not co-evolved alongside them. As such, it is crucial to investigate how pathogens may be exchanged between non-native and native bees. In this study, I investigated the potential for chalkbrood disease to spillover between two closely related mason bee species (Osmia lignaria and Osmia cornifrons). To test this, I cross-infected chalkbrood disease isolated from each species into larvae from the other, using chalkbrood disease isolated from honey bees (Apis mellifera) as an outgroup. Then, I measured mortality and sublethal effects from larval development to adult emergence. I found no evidence of infection when larvae were fed honey bee-chalkbrood; however, there was significant mortality and delayed development when fed chalkbrood from either mason bee species. Though nuanced, this implies the potential for pathogen spillover between closely related species of mason bees and harmful effects if it occurs. Ultimately, the results of this study will provide important management implications for these economically important pollinators and give us a better understanding of bee disease dynamics."
Marissa Sandoval's Abstract
"Pollinators visit flowers for a variety of rewards, most commonly pollen and nectar; but there exist specialized relationships in which flowers have evolved to offer scent and floral oils as their main reward. This interaction is common among euglossine bees, commonly referred to as orchid bees, and their mutualist orchid partners. Male orchid bees visit orchids and other 'perfume flowers' to collect fragrances from which they create a pheromone analogue to attract mates. Asymmetrical relationships in which many sympatric orchid bee species visit the same orchids for scent collection are common and well documented, however, there are select cases in which an orchid relies on a single species of bee for pollination services. Such mutualisms represent a unique opportunity to explore the interdependence of each partner for its reproductive success. Using a combination of chemical analytical techniques paired with pollinator observations, we investigated the perfume of the orchid bee Euglossa obrima and the floral volatiles of orchid Gongora galeata in Veracruz to ask 1. What is the overlap of chemical composition between the scents and 2. How does the perfume of E. obrima differ between the flowering period and non-fowering period of its obligate orchid? Our findings will contribute to our understanding of to what extent E. obrima relies on G. galeata, with implications for the conservation on both ends of the mutualism."
List of Winners
- See complete list of 2026 winners at https://tinyurl.com/4p938tm3.
- See previous years' winners at https://tinyurl.com/bdepdhy3.
Cover image: UC Davis doctoral student Luke Doyle with his President's Prize. (Photo by Lexie Martin)