- Author: Kathy Keatley Garvey
From her post at Texas A&M University, located at College Station, 90 miles northwest of Houston, Christine Merlin basically has a front-row seat for the monarch butterfly migration.
She sees them heading to Mexico to overwinter, and she sees them returning.
But it's the science that drives her.
Merlin, an assistant professor in the Department of Biology, will speak on "The Monarch Butterfly Circadian Clock: from Clockwork Mechanisms to Control of Seasonal Migration" from 12:10 to 1 p.m., Wednesday, June 1 in Room 230 of Wellman Hall.
The seminar, sponsored by the UC Davis Department of Entomology and Nematology, will be hosted by assistant professor Joanna Chiu. It is open to all interested persons. Plans are to record it for later posting on UCTV.
"The eastern North American monarch butterfly (Danaus plexippus) has emerged as a powerful model system to study animal circadian clocks and their role in an unconventional output, the photo period-induced long-distance migration," Merlin says in her abstract.
"Circadian clocks are endogenous 24-hour timekeepers that coordinate nearly all of the animal physiology and behavior to its environment to tune specific activities at the most advantageous time of the day. Monarchs use a circadian clock to navigate to their overwintering sites during their seasonal long-distance migration. The clock time-compensates for the movement of the sun across the sky over the course of the day and regulates the sun compass output in the brain. Circadian clocks could also be used to time the monarch seasonal departure from their breeding grounds, and consequently regulate the genetic/epigenetic program controlling migratory physiology and behavior."
"I will discuss progress that our lab has made in developing reverse-genetics in the monarch butterfly to unlock its potential as a genetic model system to study animal clockwork mechanisms and the involvement of the circadian clock in insect photoperiodic responses," she says. "And if we can show this is the case and that the circadian clock is involved, we can now start to understand the genetic program that is allowing the migratory behavior."
In a Texas A&M news story, Vimal Patel described her as trying to unravel "the mysteries of the migration and the role of internal clocks in the process."
"It's incredible how such a fragile insect can complete a long-range migration so demanding," Merlin told Patel. "Every piece of it fascinates me, from how it occurs to why they go precisely where they go."
An excerpt from Patel's piece:
"While she was a postdoctoral researcher at the University of Massachusetts Medical School in the laboratory of Prof. Steven Reppert, Merlin and colleagues showed that the clocks necessary for flight orientation lie in the creatures' antennae --a departure from the previous conventional wisdom that the brain controlled the mechanism, given that it controls behavioral rhythmicity in virtually every other animal, including humans.
"The conclusion stemmed from Merlin's and her co-workers' collective curiosity concerning a decades-old anecdote. Around 50 years ago, entomologist Fred Urquhart found that Monarchs became disoriented after he clipped off their antennae. Since then, it had remained just a suspicion until the Massachusetts team confirmed it with more rigorous research."
"The team's experiment exploited technology in a way Urquhart, who merely observed the Monarchs in flight, could not at the time. They used a plastic barrel-like device called a Mouritsen-Frost flight simulator in which a butterfly is connected by tungsten wire to an output system that indicates which direction it is flying. The results were clear: The antennae-less Monarchs flew in every which direction, while those with intact antennae flew southwesterly, the migratory direction."
Merlin points out that "Migration begins every year in the fall, when the day lengths change. The shortened day lengths might be a cue for the monarchs to start their migration. And if we can show this is the case and that the circadian clock is involved, we can now start to understand the genetic program that is allowing the migratory behavior."
A native of France, Merlin received her bachelor's, master's and doctoral degrees majoring in animal biology, invertebrate physiology and insect physiology, respectively, at the University Paris 6 Pierre and Marie Curie in France. She accepted a postdoctoral fellowship at the University of Massachusetts in 2007.
- Author: Kathy Keatley Garvey
Ever seen a mob of tiny sweat bees?
The bees below, from the genus Lasioglossum (as identified by native pollinator specialist Robbin Thorp, distinguished emeritus professor of entomology at the University of California, Davis), just about flash-mobbed an Iceland poppy.
These hungry little bees were a sight to see.
The genus, the largest of all bee genera, contains more than 1700 species in numerous subgenera worldwide, according to Wikipedia. "They are highly variable in size, coloration, and sculpture; among the more unusual variants, some are cleptoparasites, some are nocturnal, and some are oligolectic. Most Lasioglossum nest in the ground, but some species nest in rotten logs."
Why are they called "sweat bees?" Not an attractive name, is it? Well, they're called sweat bees because they're attracted to the salt in human sweat.
- Author: Kathy Keatley Garvey
Possession is nine-tenths of the law.
It also applies to bees foraging on lavender.
A black-faced bumble bee (Bombus californicus) this morning stretched between two lavender stems and lingered there--probably to warm its wings for flight. Along comes a honey bee (Apis mellifera) interested only in foraging for nectar.
The bumble bee holds its ground--or the stems.
The honey bee glances over at the yoga pose, sips some nectar, and buzzes off--this time probably hoping for an unoccupied blossom.
So, what does "possession is nine-tenths of the law" really mean?
Says Wikipedia: "Although the principle is an oversimplification, it can be restated as: 'In a property dispute (whether real or personal), in the absence of clear and compelling testimony or documentation to the contrary, the person in actual, custodial possession of the property is presumed to be the rightful owner."
When we left the lavender patch, the bumble bee was still in possession. But they did share. Momentarily.
- Author: Kathy Keatley Garvey
First, there's the upcoming free public event, the Zika Public Awareness Symposium, set Thursday, May 26 from 6:30 to 8:30 p.m. in Room 1001 of Giedt Hall. Professor Walter Leal of the Molecular and Cellular Biology and 18 of his biochemistry students are organizing it. Leal, a chemical ecologist, collaborates with fellow mosquito researchers in his native Brazil.
Secondly, medical entomologist Greg Lanzaro, a professor in the the UC Davis Department of Pathology, Microbiology and Immunology, will speak on “Mendel, Mosquitoes and Malaria: Applying Modern Genetics to Control an Ancient Disease” at a Davis Science Café presentation at 5:30 p.m., Wednesday, June 8 in the G Street Wunderbar, 228 G St., Davis. It's free and open to the public.
The third event is not a pending event, but a pivotal one. It's a TEDx must-watch-and-share presentation by graduate student Ralph Washington Jr. of the UC Davis Department of Entomology and Nematology. His topic: "Science, Poverty, and the Human Imagination." He mentions his fascination with mosquitoes, including Aedes aegypti, the mosquito that transmits dengue, yellow fever, chikungunya and Zika viruses.
First, a little about each:
"It is very important that students and the public-at-large learn how to prevent a possible Zika epidemic as this is the first virus known to be transmitted both sexually and by mosquitoes," said coordinator Walter Leal, a chemical ecologist and professor in the UC Davis Department of Molecular and Cellular Biology and former chair of the UC Davis Department of Entomology.
"We thought that we did not have the vector (the yellow mosquito), but now our research in collaboration with Brazilian scientists indicates that our local mosquitoes (Culex) are also competent vectors," Leal said. "And more and more we hear cases of travelers returning home infect with Zika virus. I am so glad that a group of 18 students who took my biochemistry class last quarter decided to launch this initiative to educate their peers and citizens of Davis about this dangerous virus."
The scientific-based symposium will include expert panels and speakers throughout the United States and the world, including those working on the front lines of the Zika epidemic.
The agenda:
The Zika Epidemic – An Overview
Professor Walter S. Leal
UC Davis Department of Molecular and Cellular Biology
Congenital Zika Syndrome
Dr. Regina Coeli Ramos, University of Pernambuco, Brazil (remote)
Zika Virus and Me
Professor Brian Foy
Department of Microbiology, Immunology, and Pathology, Colorado State University
Zika Virus: Looking into Mosquitoes' Vectorial Capacity
Professor Constância F. J. Ayres
Department of Entomology, Fundação Oswaldo Cruz-Pernambuco, Brazil (remote)
Don't Let Mosquitoes Bug You with Zika – Repel Them
Professor Walter S. Leal
UC Davis Department of Molecular and Cellular Biology
DEET vs. Zika – I Would Go with the Former
Dr. Emanual Maverakis
Department of Dermatology, UC Davis School of Medicine
Keeping Mosquito at Bay, Not in Your Backyard
Dr. Paula Macedo
Laboratory Director, Sacramento-Yolo Mosquito & Vector Control District
Friends Don't Let Friends Get Zika
Dr. Stuart H. Cohen
Chief of the Division of Infectious Diseases and director of Hospital Epidemiology and Infection Control, UC Davis Medical School.
Attendance to the symposium is free, but due to limited space, those planning to attend are asked to RSVP to ucdstudentsagainstzikav@gmail.com.
'Mendel, Mosquitoes and Malaria: Applying Modern Genetics to Control an Ancient Disease': Wednesday, June 8, G Street Wunderbar, Davis
UC Davis medical entomologist Greg Lanzaro, a professor in the the UC Davis Department of Pathology, Microbiology and Immunology, UC Davis School of Veterinary Medicine, is the invited speaker at the Davis Science Café presentation at 5:30 p.m., Wednesday, June 8 in the G Street Wunderbar, 228 G St., Davis.
The event, billed as "A Conversation with Professor Lanzaro," will be hosted by Professor Jared Shaw of the UC Davis Department of Chemistry. Shaw founded the Davis Science Café in 2012. It's held the second Wednesday of each month and is free and open to the public. This is a good opportunity to learn more about mosquitoes and the research underway.
Lanzaro, a noted malaria mosquito researcher, is the former director of the UC Statewide Mosquito Research Program. Science Café is affiliated with the Capital Science Communicators.
This is an inspiring presentation by Ralph Washington Jr., a National Science Foundation Graduate Research Fellow, and a second-year Ph.D. student in Entomology and Nematology. He chairs the UC Davis Graduate Student Association, co-chairs the UC Council of Student Body Presidents, and is one of the leaders of the UC Davis Black Graduate and Professional Students Association. He is committed to science and social justice and seeks a career as a research professor. He seeks to encourage children, especially low-income children, to study science. (Watch video on TEDx) (Watch video on YouTube)
In his presentation, Washington, who grew up in Oak Park, an impoverished Sacramento neighborhood, says that "The most important thing you should know about my childhood, is that I once knew hunger so well that the pangs were my closest friends. I was hungry for food, I was hungry for emotional stability and I also was hungry for knowledge."
He goes on to talk about children's innate curiosity and that we need to give them "the spark to ignite their imagination."
Mosquitoes also enter the picture. “Mosquitoes have very interesting biology," Washington says. "Some spend winter frozen in blocks of ice whereas others develop in lakes as alkaline as ammonia, more than twice as salty as seawater and as hot as a scalding shower. Some develop in empty snail shells or the tops of concave mushrooms or in a horse's hoof prints."
Be sure to tune in to hear what Washington says about several mosquitoes, including Aedes aegypti and its courtship. You'll remember what he says the next time a mosquito buzzes around you.
- Author: Kathy Keatley Garvey
He's racing through the lavender patch at breakneck speed, as if he's going to be charged with nectar robbing.
The male Bombus vandykei, an engaging blond bumble bee, twists, turns and zig-zags through the long-stemmed lavender. There is no one in pursuit.
Well, except for me and my trusty camera. I'm stationary. The camera is not. Neither is Mr. Van Dyke.
In his morning mission for flight fuel, the golden blob of a bumble bee visits a dozen lavender blossoms, sipping breakfast as if it's a smoothie, and then he's off and running. Buzzing, really. I don't know where he's going but I hope he knows where he went. The welcome mat is out.
Just another day in the lavender patch. But a beautiful day to sight the male Van Dyke bumble bee.
