- Author: Kathy Keatley Garvey
But newly published research by UC Davis agricultural entomologist Christian Nansen and insect physiologist Michael Strand of the University of Georgia reveals a new, non-destructive and quite accurate method to characterize physiological responses to parasitism: proximal remote sensing or body reflectance response data.
They published their research, “Proximal Remote Sensing to Non-Destructive Detect and Diagnose Physiological Response by Host Insect Larvae to Parasitism,” Dec. 4 in the journal Frontiers in Physiology.
Nansen, first author of the paper and an associate professor in the UC Davis Department of Entomology and Nematology, specializes in insect ecology, integrated pest management and remote sensing. Strand, a professor of entomology at the University of Georgia, is an international authority on the physiology of insect parasitism.
The scientists studied two common parasitic wasps or parasitoids, Microplitis demolitor, and Copidosoma floridanum, which lay their eggs in the larval stages of the soybean looper moth, Chrysodeixis includens. The pest, found throughout much of North and South America and elsewhere, feeds on soybeans.
“Based on reflectance data acquired three to five days post-parasitism, all three treatments (control larvae, and those parasitized by either M. demolitor or C. floridanum) could be classified with more than 85 percent accuracy,” they wrote.
Due to parasitism-induced inhibition of growth, “it's easy to differentiate soybean loopers parasitized by M. demolitor from non-parasitized larvae as long as the developmental stage of the host larva is known,” they said. In addition, a single M. demolitoroffspring emerges from the host larva 7-9 days post-parasitism to pupate, while non-parasitized larvae continue to increase in size to the final instar.
Copidosoma floridanum minimally alters host growth until late in the final instar, when thousands of wasp progeny complete their development. This wasp is known for having the largest recorded brood—3,055 individuals--of any parasitoidal insect.
The researchers said that the accuracy rate of more than 85 percent holds promise. “The hyperspectral proximal imaging technologies represent an important frontier in insect physiology, as these technologies can be used non-invasively to characterize physiological response across a range of time scale factors, such as minutes of exposure or acclimation to abiotic factors, circadian rhythms, and seasonal effects. Although this study is based on data from a host-parasitoid system, results may be of broad relevance to insect physiologists.”
Both of the wasps they studied are idiobionts and endoparasitoids.
Nansen noted that “many species of minute wasps are parasitoids of eggs and larvae of other insects, and parasitism represents one of the most extreme life strategies among animals”
“Living inside the body of another animal,” he said, “poses a series of non-trivial challenges, including how to overcome/suppress the defense response by the host; how to obtain oxygen; how to feed on the host without killing it--because once the host is dead, then microbial organisms and general decomposition will make the host body unsuitable--and how to manage waste.”
Nansen likened the developing parasitoids to astronauts flying in a space capsule. “A developing parasitoid faces a long list of serious practical challenges, so the evolutionary selection pressure has been immense and lead to some of the most extreme cases of co-evolution.”
And those soybean loopers? Those major pests of soybeans? Thanks to this research, we now know more about physiological responses to parasitism--and there's more to come. (We're also admiring the amazing photography of Jena Johnson!)
As the researchers said: "The hyperspectral proximal imaging technologies represent an important frontier in insect physiology."
- Author: Kathy Keatley Garvey
Long time passing
Where have all the flowers gone?
Long time ago
Where have all the flowers gone?
Girls have picked them every one
When will they ever learn?
When will they ever learn?"
--Pete Seeger
The late folksinger and social activist Pete Seeger (1919-2014) sounded many alarms, but a recent article in the New York Times Magazine struck a different but somewhat similar chord: the declining population of insects worldwide.
Brooke Jarvis's piece on "The Insect Apocalypse Is Here," published Nov. 27, should be required reading.
Basically: Where have all the insects gone? What does it mean? Why haven't we noticed? And what are we going to do about it?
Well, butterfly guru/entomologist Art Shapiro, distinguished emeritus professor of evolution and ecology at the University of California, Davis, has noticed. Shapiro has monitored butterfly population trends on a transect across central California for 46 years and maintains a research website at http://butterfly.ucdavis.edu/. The 10 sites stretch from the Sacramento River Delta through the Sacramento Valley and Sierra Nevada mountains to the high desert of the Western Great Basin. Shapiro visits his sites every two weeks "to record what's out" from spring to fall. The largest and oldest database in North America, it was recently cited by British conservation biologist Chris Thomas in a worldwide study of insect biomass.
In her article, Jarvis related: "In October, an entomologist sent me an email with the subject line, “Holy [expletive]!” and an attachment: a study just out from Proceedings of the National Academy of Sciences that he labeled, “Krefeld comes to Puerto Rico.” (See news article on Krefeld's "Insect Armageddon.")
That entomologist was Art Shapiro.
Pesticides, loss of habitat, diseases, climate change, and human encroachment--and more--are some of the reasons why our global population of insects is dwindling.
Shapiro, who engaged in a 90-minute conversation with author Jarvis (and suggested topics and interviews for the piece), is quoted as having one of the few long-term data sets about insect abundance in the United States.
"In 1972, he began walking transects in the Central Valley and the Sierras, counting butterflies," Jarvis wrote. "He planned to do a study on how short-term weather variations affected butterfly populations. But the longer he sampled, the more valuable his data became, offering a signal through the noise of seasonal ups and downs. 'And so here I am in Year 46,' he said, nearly half a century of spending five days a week, from late spring to the end of autumn, observing butterflies. In that time he has watched overall numbers decline and seen some species that used to be everywhere — even species that 'everyone regarded as a junk species' only a few decades ago — all but disappear. Shapiro believes that Krefeld-level declines are likely to be happening all over the globe. 'But, of course, I don't cover the entire globe,' he added. 'I cover I-80.'"
Jarvis quotes plant ecologist Hans de Kroon of Radboud University, the Netherlands, as characterizing the life of many modern insects as trying to survive from one dwindling oasis to the next but with “a desert in between, and at worst it's a poisonous desert.”
Why should we care? As Jarvis succinctly points out: "Insects are the vital pollinators and recyclers of ecosystems and the base of food webs everywhere."
So true.
Now the concern should not only be "Where have all the insects gone?" but "What are we going to do about it?"
- Author: Kathy Keatley Garvey
The incredible University of California Linnaean Games Team, comprised of graduate students from UC Davis and UC Berkeley, won the national championship at the popular and highly competitive Linnaean Games hosted this week at the Entomological Society of America's meeting in Vancouver, B.C.
This makes the third year that a UC Davis-based team has won the national championship.
"In the final, UC defeated Texas A&M (graduate students), 140-20," said Joe Rominiecki, manager of communications for the Entomological Society of America (ESA). "UC defeated the University of Florida 110-100 in the semifinal round. In the preliminary round, UC defeated the Texas A&M undergrad team."
The Linnaean Games, launched in 1983, are lively question-and-answer, college bowl-style competitions on entomological facts and played by winners of the ESA branch competitions. The teams score points by correctly answering random questions.
The UC team is comprised of captain Ralph Washington Jr., a UC Davis entomology graduate who is studying public policy at UC Berkeley; UC Davis doctoral students Brendon Boudinot, Jill Oberski and Zachary Griebenow, all of Phil Ward lab, specializing in ants; and UC Davis doctoral student Emily Bick of the Christian Nansen lab, a lab that specializes in insect ecology, integrated pest management and remote sensing.
In the first round, the UC team defeated the Texas A&M undergrads, the defending champions, by 120 to 0. "In the second round, we played Florida (including doctoral candidate David Plotkin, who specializes in the systematics and morphology of emerald moths), and won it in a nail-biting competition down to the last question!" said Boudinot. "Our final round was against the Texas A&M grads."
"Before us, there was a sudden death double overtime game (Texas A&M grads vs University of Delaware) which was really exciting," Boudinot said.
Griebenow recalled that among the questions the UC team correctly answered in the championship round:
Question: The longest-lived lepidopteran is a wooly-bear moth in the Arctiidae. In what habitat would you find these?
Answer: Arctic tundra
Question: The Passandridae are a family of beetles. What is unusual about their larvae?
Answer: The larvae are e ectoparasitoids of wood-boring insects.
The UC Davis Linnaean Games Team, captained by Washington, won the national championship twice, defeating the University of Georgia in 2016 and the University of Florida in 2015. Boudinot served on both championship teams, and Bick, the 2016 team. Last year UC Davis did not compete. Texas A&M won the national championship, with Ohio State University finishing second.
Each ESA branch hosts a Linnaean game competition at its annual meeting. The winning team and the runner-up both advance to the national competition. The national preliminaries took place Sunday, Nov. 11 while the finals got underway at 5 p.m. on Tuesday, Nov. 13.
Members of the winning team will each receive a gold medal and and a plaque for the team's department.
To get to the national finals, the UC team won the regional championship hosted by the Pacific Branch of ESA at its meeting June 10-13 in Reno. They defeated Washington State University in a sudden death overtime to win the title.
Congrats, UC Linnaean Team!
(Editor's Note: More information and photos are pending.)
- Author: Kathy Keatley Garvey
It was, though.
And it will be again when it's rebuilt.
#ParadiseStrong.
The raging inferno known as "Camp Fire" that started Nov. 8 on Camp Creek Road, near Pulga, Butte County, California, ranks as the deadliest and most destructive wildfire in the state's history.
As of today: 48 fatalities, 130,000 acres burned, and at least 8,817 structures destroyed, including almost all of what was the city of Paradise.
“Ninety-five percent of the town is gone,” Paradise council member Michael Zuccolillo told the San Francisco Chronicle in a news story published Nov. 10. “The remaining 5 percent of buildings are barely standing. I felt like I was living in a bad dream. It was unrecognizable. I had to keep asking, ‘Where are we?' All the landmarks are gone. Block by block, nothing. Anybody who had a house in Paradise probably doesn't anymore.”
"Anybody who had a house in Paradise probably doesn't anymore.”
On the UC Davis front, a couple with ties to the Bohart Museum of Entomology lost their home.
Entomologist Brennen Dyer, a specialist at the Bohart Museum, and his wife, Carol, are reeling from the tragedy. Carol barely escaped with her life.
Dyer, who grew up in Paradise and earned a bachelor of science degree in entomology from UC Davis last spring, related that he and Carol had been renting a house there while he was attending college--first at Butte Community College, and then at UC Davis. "I was a tutor at my community college," he said, "and became one again for Lynn's entomology lab." That would be Lynn Kimsey, director of the Bohart Museum and UC Davis professor of entomology.
It was Professor Kimsey who encouraged him to set up a gofundme page.
"Brennen and his wife Carol, lost their home in Paradise in the Camp Fire on Friday," Kimsey related. "I encouraged him to start a gofundme page to raise funds to pay for housing. Even though he's renting a room in an apartment in Davis, it's not enough room for both of them (she lived and worked in Paradise). Carol only managed to save some clothes before escaping the fire. They have no money saved due in part to student loans and will need several thousand dollars for first and last month's rent and security deposit for an apartment in Woodland."
"Also, the donation jar at the Bohart Museum (located in Room 1124 of the Academic Surge Building on Crocker Lane) will go to them and any profits from the gift shop, so come and shop," said Tabatha Yang, education and outreach coordinator. "This starts now and will go through Sunday during our open house on Urban Entomology from 1 to 4 p.m."
On the gofundme page, Brennen wrote: "It's hard for Carol and I to ask for help, but we have to. We lost our home in Paradise to the Camp Fire. Carol barely escaped with her life. My childhood home, along with the rest of my hometown, is gone. The only way forward for us is to rebuild our lives. I'm trying to find a house or duplex for rent near Davis. I only recently graduated from UC Davis and we have no savings so we can't afford to secure a new lease. We need $3000-5000 for deposit and first month's rent. I think we can get by under our own power after we have housing, but securing a place is the top priority."
The gofundme address is: https://www.gofundme.com/bandcparadisecampfire
#ParadiseStrong.
#DyerStrong.
We can do this!
- Author: Kathy Keatley Garvey
It's Halloween and scores of trick-or-treaters are donning monarch butterfly costumes.
But they can't do justice to the living monarchs, those iconic, majestic butterflies that are always dressed in Halloween colors: black and orange.
It's always a treat to see them but they have to avoid the "tricks"--predators and parasitoids.
Among the last monarchs we reared in September: a brightly colored female, healthy and strong and rarin' to go.
Where is she now, on Halloween? Is she overwintering in Santa Cruz or Pacific Grove? Or, did a predator, perhaps a California scrub jay or a praying mantis, nail her?
We don't known "witch" way she went, but as she fluttered away, we wished her "Safe travels!"
It's been a troubling year for monarchs, Danaus plexippus, according to butterfly guru Art Shapiro, UC Davis distinguished professor of evolution and ecology, who maintains a research website, Art's Butterfly World. "I have not seen a wild egg or caterpillar of the monarch this entire calendar year at low elevations," he said Sept. 6, 2018 during an interview on the "Insight with Beth Ruyak" program, Capital Public Radio, Sacramento. "Not one." (Listen to the interview.)
Where to see the overwintering monarchs in California?
They've been found at more than 400 sites along the California coast, according to the Xerces Society for Invertebrate Conservation. "The mild winters of the California coast are a perfect haven from the harsh cold weather found in our country's interior," Xerces says on its website. "Monarchs take advantage of this climate and often use the same overwintering sites year after year. Congregations of overwintering monarchs have been found at more than 400 sites along the California coast, from Mendocino County in the north to San Diego in the south. For many people, the arrival of autumn along the California coast is marked by the flutter of orange and black as monarchs arrive at these groves and settle in for the winter."
"The last few years have witnessed low numbers of butterflies throughout the region compared to the late 1990s, but there are still many places to view overwintering monarchs and get involved!"
Check out the Xerces' map showing monarch overwintering sites in California.
