- Author: Kathy Keatley Garvey
Those are some of the questions that Wolf asks. "We aim to find some of the molecular and neural circuit mechanisms that govern adult behavior in the fruit fly Drosophila."
Wolf, who holds a doctorate in molecular and cell biology from UC Berkeley, will speak on "Drinking Drosophila and Drunk Drosophila: Genes and Circuits for Simple Behaviors" at the next UC Davis Department of Entomology and Nematology seminar, set for 4:10 p.m., Wednesday, Oct. 31 in 122 Briggs Hall.
"How is motivation coded in a small brain?" Wolf asks. "How does a natural motivation like a thirst differ from drug-seeking in addiction? We use circuit mapping, genetics and behavior in Drosophila melanogaster to find out internal states combine with environmental information to select behavioral programs and suppress others."
Molecular geneticist Joanna Chiu, associate professor and vice chair of the UC Davis Department of Entomology and Nematology, will introduce the speaker and serve as the host. Medical entomologist Geoffrey Attardo coordinates the fall seminars.
The Drosophila fly nervous system is remarkable. Wolf says it's "a million-fold simpler than ours, yet flies are capable of carrying out remarkably sophisticated tasks that are modified by past experience and internal states. However, the biological bases for even simple behavioral actions that serve as models for more complex tasks remain mysterious. Understanding how circuits function in a model organism where rapid progress can be made with highly sophisticated tools is likely to provide insight into how more complicated brains work."
No wonder that Drosophila melanogaster, is a favorite model organism among biomedical researchers.
"There are many technical advantages of using Drosophila over vertebrate models; they are easy and inexpensive to culture in laboratory conditions, have a much shorter life cycle, they produce large numbers of externally laid embryos and they can be genetically modified in numerous ways," according to Barbara Jennings in ScienceDirect.com. "Research using Drosophila has made key advances in our understanding of regenerative biology and will no doubt contribute to the future of regenerative medicine in many different ways."
"Over the past four decades," Jennings points out, "Drosophila has become a predominant model used to understand how genes direct the development of an embryo from a single cell to a mature multicellular organism." Indeed, numerous scientists have won Nobel Prizes for their research on the fruit fly.
What does the scientific name, Drosophila melanogaster, mean? Drosophila means "dew lover" and melanogaster means "dark gut."
- Author: Kathy Keatley Garvey
If you've been following the innovative work of agricultural entomologist and remote sensing technology researcher Christian Nansen, associate professor of entomology at the University of California, Davis, you can.
Using Skittles (candy), magnolia leaves, mosquito eggs and sheets of paper, Nansen explored how light penetrates and scatters--and found that how you see an object can depend on what is next to it, under it or behind it.
He published his observations in a recent edition of PLOS ONE, the Public Library of Science's peer-reviewed, open-access journal. He researches the discipline of remote sensing technology, which he describes as “crucial to studying insect behavior and physiology, as well as management of agricultural systems.”
Nansen demonstrated that several factors greatly influence the reflectance data acquired from an object. “The reflected energy from an object--how it looks-- is a complex cocktail of energy being scattered off the object's surface in many directions and of energy penetrating into the object before being reflected,” Nansen pointed out. “Because of scattering of light, the appearance--or more accurately the reflectance profile--of an object depends on what is next to it! And because of penetration, the appearance of an object may also be influenced by what is behind it!”
“The findings are of considerable relevance to research into development of remote sensing technologies, machine vision, and/or optical sorting systems as tools to classify/distinguish insects, seeds, plants, pharmaceutical products, and food items.”
In the PLOS ONE article, titled “Penetration and Scattering—Two Optical Phenomena to Consider When Applying Proximal Remote Sensing Technologies to Object Classifications,” Nansen defines proximal remote sensing as “acquisition and classification of reflectance or transmittance signals with an imaging sensor mounted within a short distance (under 1m and typically much less) from target objects.”
“Even though the objects may look very similar--that is, indistinguishable--to the human eye, there are minute/subtle differences in reflectance in some spectral bands, “ Nansen said, “and these differences can be detected and used to classify objects.”
With this newly published study, Nansen has demonstrated experimentally that imaging conditions need to be carefully controlled and standardized. Otherwise, he said, “penetration and scattering can negatively affect the quality of reflectance data, and therefore, the potential of remote sensing technologies, machine vision, and/or optical sorting systems as tools to classify objects. “
Nansen described the rapidly growing number of studies describing applications of proximal remote sensing as “largely driven by the technology becoming progressively more robust, cost-effective, and also user-friendly.”
“The latter,” he wrote, “means that scientists who come from a wide range of academic backgrounds become involved in applied proximal remote sensing applications without necessarily having the theoretical knowledge to appreciate the complexity and importance of phenomena associated with optical physics; the author of this article falls squarely in that category!”
“Sometimes experimental research unravels limitations and challenges associated with the methods or technologies we use and thought we were so-called experts on,” Nansen commented.
Nansen, who specializes in insect ecology, integrated pest management, and remote sensing, joined the UC Davis faculty in 2014 after holding faculty positions at Texas A&M, Texas Tech and most recently, the University of Western Australia.
- Author: Kathy Keatley Garvey
Vannette, who researches pollinator microbiomes, titled her innovative project “Characterizing the Structure and Function of Pollinator Microbiomes." She investigates the communities of bacteria and fungi in flowers and pollinators, including bees and hummingbirds. “Our work to date suggests that microbes in flowers are common and influence pollinator behavior,” she says.
The Hellman funding will allow her to link microbial communities in flowers with their influence on pollinators by examining microbial modification of nectar and pollen chemistry, and examine how microbial effects vary among plant and pollinator species, and with environmental variation.
We remember the groundbreaking research published by Vannette and her colleagues last year in the New Phytologist journal. Their paper, titled “Nectar-inhabiting Microorganisms Influence Nectar Volatile Composition and Attractiveness to a Generalist Pollinator,” showed that nectar-living microbes release scents or volatile compounds that can influence a pollinator's foraging preference.
Nectar-inhabiting species of bacteria and fungi “can influence pollinator preference through differential volatile production,' Vannette related last September. “This extends our understanding of how microbial species can differentially influence plant phenotype and species interactions through a previously overlooked mechanism. It's a novel mechanism by which the presence and species composition of the microbiome can influence pollination. Broadly, our results imply that the microbiome can contribute to plant volatile phenotype. This has implications for many plant-insect interactions.”
The 11 Hellman Fellows will receive a total of $244,000 in grants for research in a wide range of disciplines. Since 2008, UC Davis has received nearly $3 million in Hellman grants, awarded to 136 early-career faculty members. The Hellman Fund provides grant monies to early career faculty on all 10 UC campuses, as well as to four private institutions.
Vannette joined the UC Davis Department of Entomology and Nematology in 2015 after serving as a postdoctoral fellow at Stanford University's biology department, where she was a Gordon and Betty Moore Foundation Postdoctoral Fellow from 2011 to 2015 and examined the role of nectar chemistry in community assembly of yeasts and plant-pollinator interactions.
She received her bachelor of science degree, summa cum laude, in 2006 from Calvin College, Grand Rapids, Mich., and her doctorate from the University of Michigan's Department of Ecology and Evolutionary Biology, Ann Arbor, in 2011. Her thesis: “Whose Phenotype Is It Anyway? The Complex Role of Species Interactions and Resource Availability in Determining the Expression of Plant Defense Phenotype and Community Consequences.”
We look forward to hearing more about this exciting research!
- Author: Kathy Keatley Garvey
Insects are in. They're not only everywhere in nature (well, almost everywhere!), they've climbed, crawled, jumped, buzzed, fluttered, flew or otherwise positioned themselves on fashions, including the UC Davis Entomology Graduate Student Association (EGSA) t-shirts.
The EGSA, comprised of UC Davis graduate students who study insect systems, is an organization that "works to connect students from across disciplines, inform students of and provide opportunities for academic success, and to serve as a bridge between the students and administration," according to EGSA president Brendon Boudinot, an ant specialist/doctoral student in the Phil Ward lab.
As a year-around fundraising project, they sell t-shirts, which can be viewed and ordered online at https://mkt.com/UCDavisEntGrad/. Jill Oberski, a graduate student in the Phil Ward lab, serves as the t-shirt sales coordinator. She can be reached at jtoberski@ucdavis.edu.
Oberski designed an award-winning onesie, “My Sister Loves Me." It's an adult ant, “loosely based on Ochetellus, a mostly-Australian genus.”
Boudinot's award-winning design is REPRESANT, with illustrations by colleague Eli Sarnat, an alumnus of the Ward lab.
One of the favorite bee t-shirts depicts a honey bee emerging from its iconic hexagonal cells. It's the 2014 winner by then doctoral student Danny Klittich, now a California central coast agronomist.
Another "fave" bee shirt--this one showing a bee barbecuing--is by doctoral student and nematologist Corwin Parker, who studies with Steve Nadler, professor and chair of the UC Davis Department of Entomology and Nematology. It was one of the 2018 winners. (See the three winners on this site.)
EGSA is heading for the Entomological Society of America annual meeting in November. In addition to their participation, the graduate students will be selling shirts at the meeting, appropriately themed "Sharing Insects Globally." It's set for Nov. 11-14 in Vancouver, B.C. The EGSA also sells its t-shirts at other events, including at Briggs Hall during the annual UC Davis Picnic Day.
Insects rock. But some climb, crawl, jump, flutter, buzz, fly or otherwise position themselves on EGSA t-shirts.
- Author: Kathy Keatley Garvey
They can't drain your bank account. They can't open up new credit cards. They can't get medical treatment on your health insurance.
But they are identity thieves, nonetheless.
Meet the drone fly (Eristalis tenax), often mistaken for a honey bee.
Indeed, it's about the size of a honey bee. In its adult form, it's a pollinator, just like the honey bee.
Unlike a honey bee, however, the drone fly "hovers" over a flower before landing. And unlike a honey bee, the drone fly has one set of wings, large eyes, stubby antennae, and a distinguishing "H" on its abdomen. Robbin Thorp, UC Davis distinguished emeritus professor of entomology, jokingly calls the drone fly "The H Bee."
Drone fly larvae are known as rattailed maggots. They feed off bacteria in drainage ditches, manure or cess pools, sewers and the like.
The fly belongs to the family Syrphidae (which includes insects commonly known as syrphids, flower flies, and hover flies) in the order, Diptera. The honey bee is Apis mellifera, family Apidae, order Hymenoptera.
One's a fly. One's a bee.
Lately we've been seeing scores of drone flies nectaring on our Mexican sunflower (Tithonia).
Identify thievery does have its advantages. Wary people and predators often shy away from drone flies, thinking they are honey bees and might sting them.
Drone flies can't sting. They can't drain your bank, either.