- Author: Kathy Keatley Garvey
Eligible to apply are first and second-year students and new transfer students interested in a one-on-one training and mentorship in insect biology.
The program can provide the opportunity to learn research skills in all areas of biology, including behavior and ecology, biodiversity, agroecology, population biology, mathematical biology, human health, cell biology, biochemistry and molecular biology, said co-director and co-founder Jay Rosenheim, professor of entomology, Department of Entomology and Nematology, UC Davis.
Details are at http://ucanr.org/sites/insectscholars/
West, majoring in biochemistry and molecular biology, works in the Chiu lab on the Spotted Wing Drosophila (Drosophila suzukii or SWD), a serious pest of fruit crops. In collaboration with scientists in the U.S. and around the world, including Frank Zalom, UC Davis professor of entomology, West is surveying populations of SWD using next-generation sequencing to determine the extent of possible insecticide resistance.
West was one of eight students among a pool of 50 selected to be a member of the Class of 2013, Research Scholars in Insect Biology Program.
- Author: Kathy Keatley Garvey
Dingle, a UC Davis emeritus professor of entomology and author of two editions of “Migration: The Biology of Life on the Move,” said his previous studies reveal that migrant and resident monarchs exhibit different wing shapes.
Dingle is the recipient of the UC Davis Edward A. Dickson Professorship Award to research “Monarchs in the Pacific: Is Contemporary Evolution Occurring on Isolated Islands?”
Dingle will be working with community ecologist Louie Yang and molecular geneticist Joanna Chiu, assistant professors in the UC Davis Department of Entomology and Nematology, to examine the ecology and physiology of monarch butterflies (Danaus plexippus) in three islands where contemporary evolution might be expected. The islands are Oahu (Hawaii), Guam (Marianas) and Weno (Chuuk or Truk).
“This is the necessary first step in a long-term analysis of the evolutionary ecology and physiology of monarch butterflies on remote Pacific islands,” said Dingle, a fellow of the American Association for the Advancement of Science and the Animal Behavior Society.
Dingle said the monarch, widely distributed “for eons” in the New World, is fairly new to the Pacific islands and to Australia. “In addition to North America, the monarch occurs as a resident throughout the Caribbean and Central and northern South America—and probably as a migrant farther south. One of the more intriguing aspects of its distribution is that beginning in the early part of the 19th century, it spread throughout the Pacific all the way to Australia, where there are now well-established migratory and non-migratory populations.”
Dingle speculates that the monarchs arrived in the Pacific islands with their host plant, milkweed, which was valued at the time for its medicinal properties. Some of the islands are extremely isolated, he said.
An analysis of a monarch population in Hawaii shows that resident monarchs have shorter, broader wings than the long-distance migrants. The Hawaii butterfly wings were shorter than the eastern U.S. long-distance migrants, but “not so short-winged as the residents in the Caribbean or Costa Rica, which have been present in those locations for eons, rather than the 200 years for Hawaii.”
“If there are indeed wing shape changes associated with evolution in isolation, are there other changes that may have occurred under selection and local adaptation for residency?” Dingle wonders. “Are there other changes that may have occurred under selection and local adaptation for residency? Examples of such traits might be changes in flight muscle physiology, changes in photoperiodic diapause response, changes in the characteristics of orientation ability and its relation to antennal circadian rhythms, or changes in the reproductive capacity or tactics (re-colonization of ‘empty' habitats is no longer part of the life cycle).
“Diapause and fat storage, necessary to support migration, are triggered by short photoperiods,” Dingle said, “and the butterflies orient using a sun compass synchronized to a circadian rhythm in the antennae. Overwintering sites in North America include the Transvolcanics Mountains of central Mexico, and the California Coast, particularly Santa Cruz, Pismo Beach, and Pacific Grove.
The UC Davis team will study the monarchs on the three islands and compare them with California mainland monarchs. Using an image analyzer and camera equipment available in Yang lab, the team will photograph “chilled” butterflies in a fixed position with wings spread and then release them back into the wild. The image analyzer will measure different variables, including length, width and angles from the photographs and compute multivariate-shape parameters.
The Chiu lab will assess genetic differences using a transcriptomic approach with monarch caterpillars. “This assessment will be greatly facilitated by the fact that the monarch genome has now been sequenced,” Dingle noted. “A major focus of Dr. Chiu's research is circadian rhythm genes, and these will be especially relevant here because of the association of these genes with monarch capabilities. Because the monarch cell line is cycling and has a functional circadian clock, effects of mutations in specific clock genes can be examined with regard to clock function.”
Dingle expects the one-year research program not only to form the basis for “long-term research on the evolutionary genetics of behavior, ecology and physiology on Pacific island monarch butterflies” but on “the general aspects of island biogeography, a subject of great practical theoretical interest in evolutionary biology.”
Both Yang and Chui currently have grants involving research on monarch butterflies. Yang also studies island ecology.
Dingle, who received his bachelor's degree in zoology from Cornell University and his doctorate in zoology from the University of Michigan, served on the faculty of the UC Davis Department of Entomology (now the UC Davis Department of Entomology and Nematology) from 1982 to 2002 and achieved emeritus status in 2003. He is a past president of the Animal Behavior Society and former secretary of the International Society for Behavioral Ecology.
Dingle published the second edition of “Migration: The Biology of Life on the Move” (Oxford University Press) in November 2014. It is the sequel to the widely acclaimed first edition, published in 1996. National Geographic featured Dingle in its cover story on “Great Migrations” in November 2010. LiveScience interviewed him for its November 2010 piece on “Why Do Animals Migrate?”
Dingle was interviewed recently by Italian journalist Giovanna Faggionato for a piece on migration in the Pirelli magazine.
- Author: Kathy Keatley Garvey
His seminar will be recorded for later viewing on UCTV.
"Ecologists have long recognized that species interactions change over time, due to temporal variation in abiotic environments and in the abundance and relative life stages of interacting species," Yang says. "Despite - or perhaps because of - the ubiquitous role of time in structuring species interactions, other aspects of community complexity have often been emphasized ahead of temporal complexity. However, a growing emphasis on understanding how phenology, ontogeny, stage-structure and transient event-driven dynamics affect species interactions may signal the re-emergence of a 'temporally explicit' perspective in community ecology. A temporally explicit view of community ecology aims to understand how species interactions change over time, and the consequences of shifts in this timing."
In his talk he will suggest "how a temporally explicit view of species interactions could build upon the ubiquitous and implicit consideration of time that is already fundamental to ecology. If we step away from common simplifying assumptions about the constancy of community structure and process, what new questions emerge? This introduction to the session will attempt to identify some common themes that are emerging from a temporally explicit perspective in ecology, illustrated with examples from recent studies in multiple systems."
Yang said the key emerging themes of this synthesis are
- In systems where multiple dynamic processes operate on different timescales, it is important to consider sequential (as opposed to strictly alternative) hypotheses;
- The study of species interactions should consider both phenology and ontogeny, especially when stage-structured interactions occur throughout life histories;
- Biotic and abiotic constraints on species interactions can define windows of opportunity in time, where quantitative shifts in the timing of key events (such as physical disturbances or resource pulses) can qualitatively alter life history outcomes;
- A temporally explicit perspective seeks to explain the mechanisms of historical contingency in community assembly; and
- The continued development of a temporally explicit perspective in ecology is important for understanding how real-world species interactions are coordinated in time, and the potential implications of disrupting this coordination.
Yang's research interests include community ecology, species interactions, temporal variation, extreme events in nature, and the integration of ontogeny and phenology. Last year received a prestigious National Science Foundation Early Career Development Award of $600,000. He was one of four young UC Davis faculty members selected for the award. Yang is studying the importance of timing in interactions between plants, animals and their environment, specifically studying the monarch butterfly and milkweed. Species interactions change with the seasons and with different life stages, and climate change may disrupt these interactions, for example, if caterpillars emerge before food sources are available.
Yang earned his bachelor's degree (ecology and evolution) from Cornell University in 1999 and his doctorate from UC Davis in 2006, studying with entomology professor and ecologist Rick Karban. Yang conducted postdoctoral research at UC Santa Barbara before returning to UC Davis as a faculty member in 2009. While at UC Santa Barbara, he served as a UC President's Postdoctoral Fellow in the Department of Ecology, Evolution and Marine Biology.
- Author: Kathy Keatley Garvey
Murphy, a fourth-year UC Davis student majoring in neurobiology, physiology, and behavior, received $1563 to study “Codon Optimization: Cracking the Genetic Code.” A codon is a unit of three nucleotides that together codes for an amino acid, the building block of proteins in all organisms. Using the fly, Drosophila melanogaster, as a model system, Murphy is exploring the functional significance of codon bias, a phenomenon in which certain codons are favored over others even though they may code for the same amino acid.
Murphy has worked in the Chiu lab since 2011. “Katie is one of the most talented and hardworking student I have ever encountered,” Chiu said. “I can't think of anyone else who is more deserving of this award.”
Murphy is one of a select group of students in the Research Scholars Program in Insect Biology, organized and directed by professor Jay Rosenheim and assistant professors Louie Yang and Joanna Chiu. The program aims to provide undergraduates with a closely mentored research experience in biology.
The Provost's Undergraduate Fellowship supports undergraduate students doing research or creative projects under the guidance of UC Davis faculty members. Students from all discipline areas are eligible to apply
As a Provost fellow, Murphy will present her work at the annual UC Davis Undergraduate Research Conference, which takes place April 25–26 in Freeborn Hall.
In 2012, Murphy received a UC President's Undergraduate Research Fellowship for her research on "Transgenic Yeast as an Organic Pesticide," exploring the use of RNAi technology in combating the invasive pest, the spotted-wing Drosophila suzukii. She also received a 2013 McBeth Memorial Scholarship and a 2010 Voorhies Memorial Scholarship.
Murphy is a 2010 graduate of Kelseyville High School (Lake County) and valedictorian of her class.
“My favorite subject in high school was biology,” she recalled. “My favorite project was when we dissected a cat in anatomy. In college, I lucked into a lab job where my boss and co-workers were willing to teach me and allowed me the freedom to take on my own projects, an opportunity that few undergrads get.”
Following graduation, she plans to travel and continue her current research projects.
- Author: Kathy Keatley Garvey
In announcing the awards, Provost Ralph Hexter noted (1) that Tatiossian’s research on the walnut twig beetle makes a significant contribution to establishing an integrated pest management plan; (2) that her manuscript, “Flight Response of the Walnut Twig Beetle, Pityophthorus juglandis, to Aggregation Pheromones Produced by Low Densities of Males”; is in preparation for submission to the Journal of Chemical Ecology; and (3) that her poster received attention at a national entomology conference for the ceramic bark beetle she sculpted.
Hexter presented awards of excellence to Brenda Marin-Rodriguez and L. Carolina Tavarez. In addition to Tatiossian, honorable mentions went to Amanda Steele, biomedical engineering; Rachel Borthwell, biological sciences and art history; and Lindsey Black, history.
A photo of Tatiossian and Black appears as the cover photo on the UC Davis Undergraduate Facebook site at https://www.facebook.com/UCDavisUndergraduateEducation. Her poster, including the ceramic bark beetle she crafted, is mounted on the third floor of Briggs Hall, next to the administration office of the UC Davis Department of Entomology and Nematology.
Tatiossian, who joined the Research Scholars Program in September 2011, graduated from UC Davis in three years (she achieved the top grade point average in entomology) and is currently working in the laboratory of Diane Ullman, professor of entomology and associate dean for undergraduate academic programs in the College of Agricultural and Environmental Sciences.
Among those nominating her or supporting her nomination were her mentor, chemical ecologist and forest entomologist Steve Seybold of the Davis-based Pacific Southwest Research Station, USDA Forest Service, and an affiliate of the UC Davis Department of Entomology; professor Jay Rosenheim who co-founded and co-directs the Research Scholars Program in Insect Biology; and Diane Ullman.
Rosenheim noted that Tatiossian was a member of the first cohort of undergraduates recruited to the program. “I witnessed her tremendous determination to develop independent research skills” and she “succeeded in all phases of the project, from design, data collection, data analysis and manuscript preparation.”
Among the 30 students who have entered the program since 2011, “Kristina is absolutely the standout in terms of motivation and enthusiasm for research,” Rosenheim said. “She leaped at the opportunity to learn how to become an independent researcher. Kristina will generate the first-lead authored publication for any student in our program—hopefully, the first of many. In this sense, she has already been a trailblazer for our program.”
Seybold noted that Tatiossian “worked on the host-finding behavior of a major pest of walnut trees, the walnut twig beetle. This is a nationally significant pest that spreads a disease of live trees called thousand cankers disease (TCD). The condition threatens not only the English walnuts that form the basis of the California nut industry, but also the black walnuts that represent over $500 billion in growing stock value of fine wood products in the eastern U.S.
“Kristina formulated her research project in fall 2011 and spring 2012 and then carried it out in spring and summer 2012. As she developed the project, she also applied to the Department of Entomology for a McBeth Scholarship, which she was awarded in summer 2012. The award helped her offset the costs of her research supplies and funded her travel to several scientific meetings.”
“Kristina collected a live population of the walnut twig beetle from a traditional orchard habitat in the southern Central Valley, reared the insects to the adult stage, and re-introduced the adults into freshly cut black walnut branch sections. Once the male beetles had begun producing their aggregation pheromones (attractants) in the branch sections, Kristina used the branch sections as lures to attract new males and females into flight traps. Using this basic technique she was able to establish that as few as 1 to 5 male beetles would provide a threshold of flight behavioral attraction in the field. This finding has ramifications for establishing an integrated pest management program for the walnut twig beetle nationwide.”
Tatiossian developed and displayed her poster at the 60th Annual Meeting of the Entomological Society (ESA), held Nov. 11-14, 2012 in Knoxville, Tenn. “Her poster reached a very interested target audience because Knoxville is in the heart of the distribution of eastern black walnut trees and in the center of the current distribution of TCD in the eastern U.S.,” Seybold said. “In a very creative touch, Kristina sculpted a replica of the female walnut twig beetle (through her participation in the UC Davis Art/Science Fusion Program) and attached the sculpture directly to her poster. This elicited quite a response at the national meeting and led to a news story released by UC Davis.”
The poster also drew attention at the arts exhibit at the 24th Annual UC Davis Undergraduate Research, Scholarship and Creative Activities Conference, held April 26, 2013.
In addition, Tatiossian delivered an oral presentation on her research at the 97th Annual Meeting of the Pacific Branch of the ESA in South Lake Tahoe, Nev.
Her poster, now on permanent display at Briggs Hall, credits Seybold; Extension entomologist Mary Louise Flint, associate director for Urban and Community IPM, UC Statewide Integrated Pest Program; entomology graduate student Stacy Hishinuma, and postdoctoral researcher Yigen Chen of the UC Davis Department of Entomology. Robin Schmidt of UC Davis Molecular and Cellular Biology mounted the unusual poster with the ceramic beetle.