Cooperative Extension specialist Ian Grettenberger of the UC Davis Department of Entomology and Nematology will explore the relationships between insects and agriculture. (Photo by Kathy Keatley Garvey)

Saturday, May 28, 1 to 4 p,m.
Open house, "Bugs in Ag: What Is Eating Our Crops and What Is Eating Them?"
Cooperative Extension specialist and agricultural entomologist Ian Grettenberger of the UC Davis Department of Entomology and Nematology faculty will explore the relationships between insects and agriculture. His areas of expertise include field crops; vegetable crops; insects, mites and other arthropods affecting plants; biological control of pests affecting plants; and beneficial insects. Grettenberger, who joined the UC Davis faculty in January 2019, targets a wide variety of pests, including western spotted and striped cucumber, beetles, armyworms, bagrada bugs, alfalfa weevils, aphids, and thrips.

Saturday June 25, 1 to 4 p.m.
Open house, "Eight-Legged Encounters"
This event is all about arachnids featuring scientists from across the country. It is in collaboration with the American Arachnological Society's 2022 meeting, scheduled June 26-30 on the UC Davis campus.  The annual meeting will be hosted by two UC Davis arachnologists: Jason Bond, 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, and Joel Ledford, assistant professor of teaching, Department of Plant Biology, College of Biological Sciences.

This Bohart Museum of Entomology poster, the work of Greg Kareofelas and Fran Keller, shows the male (top) and female dogface butterfly.

Saturday, July 16, 1 to 4 p.m.
"Celebrating 50 Years of the Dogface Butterfly:California's State Insect"
Scientists and the public will celebrate the 50th anniversary of the California State Legislature' designation of the dogface butterfly as the state insect. 

Folsom Lake College professor and Bohart scientist Fran Keller, and Bohart associate Greg Karofelas, a volunteer docent for the Placer Land Trust's dogface butterfly tours, will on hand to discuss the butterfly.  The California dogface  butterfly, Zerene eurydice, is found only in California. It thrives in the 40-acre Shutamul Bear River Preserve near Auburn, Placer County.  The  preserve, part of the Placer Land Trust, is closed to the public except for specially arranged tours. 

Keller is the author of 35-page children's book, The Story of the Dogface Butterfly, with photos by Keller and Kareofelas, and illustrations by former UC Davis student Laine Bauer. Kareofelas' images include the life cycle of the dogface butterfly that he reared. Keller holds a doctorate in entomology from UC Davis, where she studied with major professor Lynn Kimsey, director of the Bohart and UC Davis distinguished professor of entomology.

Kareofelas and Keller also teamed to create a dogface butterfly poster of the male and female.  Both the book and the poster are available online from the the Bohart Museum of Entomology gift shop. 

California legislators adopted the dogface butterfly as the official state insect on July 28, 1972. But as early as 1929, entomologists had already singled it out as their choice for state insect. Their suggestion appears in the California Blue Book, published by the State Legislature in 1929. (Read more on how the butterfly became the state insect under the Ronald Reagan administration.)

The dogface butterfly is so named because the wings of the male appear to be a silhouette of a poodle. It is also known as "the flying pansy."

Bohart Museum. The Bohart Museum is the home of a worldwide collection of eight million insect specimens, plus a gift shop and a live "petting zoo," comprised of Madagascar hissing cockroaches, stick insects and tarantulas. 

Bohart Museum Contact information: 
https://bohart.ucdavis.edu/
(530) 752-0493 
bmuseum@ucdavis.edu

Crystal Homicz

The Zoom link is https://ucdavis.zoom.us/j/8120304398  

Homicz focuses her research on the interactions between bark beetles and fire, including the effect of bark beetles on tree mortality after prescribed burning and mechanical thinning in the Sierra Nevada. She is also monitoring increases in fuel loads following a western pine beetle outbreak in the southern and central Sierra Nevada. 

Homicz is advised by research forest entomologist Christopher Fettig of the Pacific Southwest Research Station, Davis, and molecular geneticist/physiologist Joanna Chiu, professor and vice chair of the department.  

Fettig was a colleague of the late Steve Seybold (1959-2019), a Pacific Southwest Research Station research entomologist and a department lecturer and researcher. Seybold, who served as Homicz' first advisor, was one of the pioneering scientists researching the newly discovered thousand cankers disease (TCD), caused by the walnut twig beetle, Pityophthorus juglandis, in association with the canker-producing fungus, Geosmithia morbida.

Homicz holds associate of science degrees in biology and natural sciences from Shasta College (2016),  and a bachelor of science degree in animal biology, with an emphasis in entomology, from UC Davis (2018). Her practicum (with Seybold as advisor): “Landing Behavior of the Walnut Twig Beetle on Host and Non-host Hardwood Trees under the Influence of Aggregation Pheromone in a Northern California Riparian Forest." 

As an undergraduate student, Homicz served in the labs of Seybold and James Carey, UC Davis distinguished professor of entomology. As a graduate student, she has served as a teaching assistant for the Animal Biology major, and Introduction to Evolution and Ecology, and as a guest lecturer (forest entomology) in Introduction to Entomology, ENT 10. She presents her research at Entomological Society of America meetings, and at forest-affiliated conferences.

Homicz taught the fundamentals of forestry, including forest ecology, forest measurements and silviculture, at an eight-week UC Berkeley Forestry Camp in 2019.  The camp culminated with a capstone project of developing a forest management plant for a 160-acre stand. 

Active in campus and community projects, Homicz is a member of the UC Davis Graduate Student Association (EGSA) and represents EGSA at meetings of the campuswide UC Davis Graduate Student Association. She is also a member and former treasurer of UC Davis Entomology Club, advised by forensic entomologist Robert Kimsey.  Homicz assisted with Kimsey's Pacific Deathwatch Beetle Surveys on Alcatraz Island.

As a volunteer at the UC Davis Bohart Museum of Entomology, Homicz sorted and identified specimens and integrated specimens into the museum collection. She also participates in the Bohart Museum outreach activities.

An article she co-authored, "Fire and Insect Interactions in North American Forests," is pending publication in Current Forest Reports. Among her other publications:

• Homicz, C.S., C.J. Fettig, A.S. Munson, and D.R. Cluck. 2022. Western pine beetle. USDA Forest Service, Forest Insect and Disease Leaflet # 1, 16pp. https://www.fs.fed.us/foresthealth/docs/fidls/FIDL-01-WesternPineBeetle.pdf
• Homicz, C.S., J. P. Audley, Y. Chen, R. M. Bostock, S. J. Seybold. 2020. Landing Behavior of the Walnut Twig Beetle on Host and Non-Host Hardwood Trees under the Influence of Aggregation Pheromone in a Northern California Riparian Forest.  Agriculture and Forest Entomology. 
• Audley, J. P., C. S. Homicz, R. M. Bostock, S. J. Seybold. 2020. A Study of Landing Behavior by the Walnut Twig Beetle, Pityophthorus juglandis, Among Host and Non-Host Hardwood Trees in a Northern California Riparian Forest. Agriculture and Forest Entomology

Ziad Khouri, doctoral student

His in-person and Zoom seminar, "Scoliid Wasp Evolution and Some Adventures with Posterior Predictive Simulation," will begin at 4:10 p.m. (Pacific Daylight Time) in 122 Briggs Hall.  The Zoom link is https://ucdavis.zoom.us/j/99515291076

Khouri will deliver his seminar in two parts:  "The Evolutionary History of Mammoth Wasps (Hymenoptera: Scoliidae)" and "Comparing the Power of Data-Based Phylogenetic Posterior Predictive Checks in the Context of Cucleotide and Amino Acid Data."

"Ziad's work on the mammoth wasps is unique," said host Kimsey, director of the Bohart Museum of Entomology and a distinguished professor of entomology. "This is a family of large bodied distinctive parasitoid wasps that have never had a modern systematic treatment, and the genus and species level taxonomy was a mess. He has brought together modern and classical techniques to bring taxonomic order to this family of wasps and discovered how they evolved."

Some 2300 mammoth wasp specimens, mostly from the Americas, Korea and South Africa, are housed in the Bohart Museum's global collection.  

Khouri shares these abstracts from his seminar:

Part 1: "The Evolutionary History of Mammoth Wasps (Hymenoptera: Scoliidae)"

Scoliid wasps comprise a clade of aculeate insects whose larvae are parasitoids of scarabaeid beetle grubs. While scoliids have been studied and used as biological control agents, research into the group's evolution, as well as the stability of scoliid taxonomy, has been limited by a lack of reliable phylogenies. We use ultraconserved element (UCE) data under concatenation and the multispecies coalescent to infer a phylogeny of the Scoliidae. In order to mitigate potential issues arising from model misspecification, we perform data filtering experiments using posterior predictive checks and matched-pairs tests of symmetry. Our analyses confirm the position of Proscolia as sister to all other extant scoliids. We also find strong support for a sister group relationship between the campsomerine genus Colpa and the Scoliini, rendering the Campsomerini non-monophyletic. Campsomerini excluding Colpa (hereafter Campsomerini sensu stricto) is inferred to be monophyletic, with the Australasian genus Trisciloa recovered as sister to the remaining members of the group. Many sampled genera, including Campsomeriella, Dielis, Megascolia, and Scolia are inferred to be non-monophyletic. Analyses incorporating fossil data indicate an Early Cretaceous origin of the crown Scoliidae, with the split between Scoliini + Colpa and Campsomerini s.s. most probably occurring in the Late Cretaceous. Posterior means of Scoliini + Colpa and Campsomerini s.s. crown ages are estimated to be in the Paleogene, though age 95% HPD intervals extend slightly back past the K-Pg boundary, and analyses including fossils of less certain placement result in more posterior mass on older ages. Our estimates of the stem ages of Nearctic scoliid clades are consistent with dispersal across Beringia during the Oligocene or later Eocene. Our study provides a foundation for future research into scoliid wasp evolution and biogeography by being the first to leverage genome-scale data and model-based methods. However, the precision of our dating analyses is constrained by the paucity of well-preserved fossils reliably attributable to the scoliid crown group. Despite concluding that the higher-level taxonomy of the Scoliidae is in dire need of revision, we recommend that taxonomic changes be predicated on datasets that extend the geographic and taxonomic sampling of the current study.

Part II: "Comparing the Power of Data-Based Phylogenetic Posterior Predictive Checks in the Context of Cucleotide and Amino Acid Data" 

When used for phylogenetic inference, exonic DNA sequences can be coded in multiple ways, including as nucleotides, amino acids, and codons. In empirical studies, the choice of data type and associated model is often predicated on which model is less expected to be violated in ways that lead to inaccurate inference. Posterior predictive checks are one method for assessing the adequacy of phylogenetic models and potentially providing an indication of inference reliability. We used a simulation-based approach to explore how our ability to detect model inadequacy using phylogenetic posterior prediction, as well as the associated inference errors, may vary with data coding. Specifically, we simulated data under multiple models, including codon models featuring process heterogeneity across lineages, selection heterogeneity across sites, and selection for codon usage. We then performed inference and posterior predictive checks under nucleotide and amino acid models from the GTR family. We found that some simulation conditions resulted in significant differences, between amino acid and nucleotide treatments, in our ability to detect model violation, even when the magnitude of error in an estimate of interest was similar. Moreover, we corroborate the results of other studies indicating that error in tree length estimation is not always correlated with error in topology reconstruction. Although the use of amino acid models generally resulted in more accurate topologies, we found tree length errors to often be greater than for nucleotide models when the data being analyzed were generated using branch-heterogeneous codon models. We show that the magnitude and direction of tree length estimation error can depend on both data coding and properties of the data-generating process. We conclude that if posterior predictive checks are to be used for purposes such as data filtering, practical effect size thresholds indicative of low inference reliability must be established separately for amino acid and nucleotide data. We also advise caution and recommend careful selection of models and data coding when performing analyses where accurate inference of tree length is important.

Khouri joined the UC Davis graduate program in 2012 and is pursuing his doctorate in entomology. His dissertation research involves the phylogenetics, evolution and taxonomy of Scolliidae (Hymenoptera) and phylogenetic posterior prediction. 

He holds a bachelor's degree in biology (2012) from Notre Dame University - Louaize (NDU). He did undergraduate research on the identification of bee and other pollinator specimens at the American University of Beirut; assessed genetic diversity in Spartium junceum populations (known as Spanish broom, rush broom, or weaver's broom); and collected specimens for the establishment of an insect collection at NDU.

The Bohart Museum, located in Room 1124 of the Academic Surge Building on Crocker Lane, is currently closed to the public. It houses eight million insect specimens, as well as a live "petting zoo" (Madagascar hissing cockroaches, stick insects and tarantuias) and an insect-themed gift shop, now online. 

Nematologist Shahid Siddique, assistant professor, UC Davis Department of Entomology and Nematology, coordinates the seminars. For any Zoom technical issues, contact Siddique at ssiddique@ucdavis.edu. (See list of seminars)

Several UC Davis scientists, including Professor Lynn Kimsey,  and Extension apiculturist Elina Lastro Niño of the UC Davis Department of Entomology and Nematology,  weighed in on "The Plight of the Pollinators," in an informative article by Ula Chrobak in the March edition of UC Davis Magazine, edited by Jocelyn Anderson. 

Kimsey, director of the Bohart Museum of Entomology and a UC Davis distinguished professor of entomology, specializes in Hymenoptera. One of her activities: she hosts the annual Robbin Thorp Memorial Bumble Bee Contest contest to determine who can find the first bumble bee of the year in the three-county area of Yolo, Solano and Sacramento.  

Niño, the statewide Extension apiculturist, serves as the director of the California Master Beekeepers' Program, and faculty director of the UC Davis Bee Haven. 

Also featured were Art Shapiro, distinguished professor of evolution and ecology, who has monitored the butterfly population of Central California since 1972; and avian veterinarian and hummingbird expert Lisa Tell, a UC Davis professor of veterinary medicine and author of a newly published children's poetry book, "If Hummingbirds Could Hum," that relates how to attract hummers.

Some resources mentioned:

• What to plant to attract bees and other pollinators: See the UC Davis Bee Haven website, directed by Niño and managed by Chris Casey. The Haven, located on Bee Biology Road, west of the central campus, is open year around, from dawn to dusk.
• What to plant to attract butterflies: See Art Shapiro's website, Art's Butterfly World 
• Sign up for bee classes with the California Master Beekeepers' Program, launched and directed by Elina Lastro Niño
• See pollinators and other insects at the UC Davis Bohart Museum of Entomology, home of a global collection of 8 million insect specimens. (The Bohart, located in Room 1124 of the Academic Surge Building, is temporarily closed due to COVID-19 pandemic precautions) 

Photographs for the UC Davis Magazine article are the work of Kathy Keatley Garvey, communications specialist with the UC Davis Department of Entomology and Nematology, and an avid pollinator photographer.

UC Davis Magazine, which has been covering the campus community since 1983, is printed in March and September. A yearly subscription is $12.