Forget the soaps; let's talk about soapberry bugs and an entomologist at the University of California, Davis, who studies them.
And why and how she decided to pursue entomology as a career. That we'll save until the end of this blog.
Doctoral candidate Meredith Cenzer of the Louie Yang lab, UC Davis just published her research on soapberry bugs, which are a classic evolutionary example of how rapidly insects can switch hosts, adapting from a native to an invasive plant.
Her research shows that soapberry bugs have not only lost adaptations to their native host plant but are regionally specializing on an invasive host.
The work, "Adaptation to an Invasive Host Is Driving the Loss of a Native Ecotype," published in the current edition of the journal Evolution, “collapses a classic and well-documented example of local adaptation,” said doctoral candidate Meredith Cenzer of the Louie Yang lab, UC Davis Department of Entomology and Nematology. The plant-host switch can lead to disruption of native plant communities and a breakdown of the ecosystem.
The players involved are the soapberry bug (Jadera haematoloma), also known as “the red-shouldered bug”; its native host plant, the balloon vine (Cardiospermum corindum), and the invasive host, the golden rain tree or Taiwanese rain tree (Koelreuteria elegans).
The study, which took place in Florida, expands on the 1989 groundbreaking research of UC Davis evolutionary ecologist and soapberry expert Scott Carroll, who documented local adaptation in beak length, survival, and development time and other traits between soapberry bugs, balloon vine and the golden rain tree in Florida.
Said Carroll: "Meredith Cenzer's findings carry an important message for those concerned with biodiversity conservation, because she shows that even highly distinct adaptive specializations can disappear rapidly due to human influence on the environment– even in cases where the key native habitat has not been lost."
The soapberry bug, which lives throughout the United States and much of the world, feeds on seeds within the soapberry plant family, Sapindaceae, which includes soapberries, boxelders and maples. Mostly black, it has red eyes, red lateral stripes on the sides of its head and red on its “shoulders” (pronotum). It is often mistaken for the boxelder bug.
“As part of my doctoral dissertation, I documented that this pattern of local adaptation has been lost in the last 27 years,” Cenzer said, “and that all populations of soapberry bugs in Florida-- even those still found on the native --are now adapted only to the invasive host.“
“Locally adapted populations are often used as model systems for the early stages of rccological speciation, but most of these young divergent populations will never become complete species,” Cenzer noted in her abstract. “The maintenance of locally adapted populations relies on the strength of natural selection overwhelming the homogenizing effects of gene flow; however, this balance may be readily upset in changing environments.”
“All populations that were adapted to the native host--including those still found on that host today--are now better adapted to the invasive host in multiple phenotypes,” she wrote in her abstract.” Weak differentiation remains in two traits, suggesting that homogenization across the region is incomplete. This study highlights the potential for adaptation to invasive species to disrupt native communities by swamping adaptation to native conditions through maladaptive gene flow.”
Cenzer characterized local adaptation as “high performance in one habitat coming at the cost of performance in other habitat types, such that populations specialized on each habitat will have higher fitness in that environment than immigrants from other habitats.”
“This results directly in two types of ecological reproductive isolation between locally adapted populations: 1) selection against migrants, who will be outcompeted by residents, and 2) selection against hybridization (if hybrids show intermediate phenotypes), as hybrid offspring will be outcompeted in each habitat by one parental type,” she wrote in her research paper. “However, such reproductive isolation relies on ongoing differential selection balanced with low rates of gene flow between habitats. In most well studied systems demonstrating local adaptation, we do not know how perturbation – either to selection pressures or gene flow – will influence the long-term stability of differentiation.”
Carroll, who maintains a website, “Soapberries of the World,” says the soapberry bugs are “very approachable native guides to how evolution is taking place on earth day.” His website shows “how evolution happens every day and why it matters.”
How did Meredith Cenzer, a native of Gainesville, Fla., become interested in entomology? We love her answer.
"I first became interested in entomology as a kid," she recalled. "The defining moment in my memory is when my gifted science teacher, Ms. Linda Osborne, told me in third grade that there are people who study insects for a living and that they're called entomologists. She was going to put me in timeout for being too loud (a lifelong problem), but told me she'd let it slide this time if I promised to become an entomologist."
"Two years later, she let me come in and teach her first graders about insects. For my first science fair project, in sixth grade, I tracked the progress of tent caterpillar aggregations; we weren't allowed to manipulate animals, so I photographed them every day and made notes on their behavior - my parents still have the poster from that one."
So, she promised her teacher she'd become an entomologist. And she kept her promise. She received her bachelor of science degree in entomology at the University of Florida in 2009.
Future plans, after receiving her doctorate in entomology from UC Davis?
“I am broadly interested in evolutionary ecology, particularly in plant-insect interactions, and the balancing roles of selection, gene flow, and plasticity on determining the phenotypes we see in nature,” she said. After receiving her doctorate in entomology from UC Davis in the fall, she will start a postdoctoral position at Florida State University with biology professor Leithen M'Gonigle, developing theory on the evolution of dispersal in patchy landscapes.
A tip of the insect net to Meredith Cenzer!
(Editor's Note: Meredith Cenzer participated in the Entomological Society of America's Linnaean Games competition in 2011. See Bug Squad blog of Nov. 22, 2011.)
Let's celebrate the Gulf Fritillary (Agraulis vanillae).
If you have a passionflower vine (Passiflora) in your yard, you've probably seen these spectacular orangish-reddish butterflies with silver-spangled underwings fluttering around--the males patrolling for females, the mating, the females laying eggs, the caterpillars hatching from the eggs, and the caterpillars munching and crunching until their last instar. Then you'll see them forming chrysalids, and butterflies eclosing.
The unseen world of Gulf Frits. The miraculous unseen world of Gulf Frits. Because it is.
That came to mind the other day when two passersby saw a dozen or so Gulf Frits heading into our yard.
"Look at all the butterflies!" one exclaimed. "I wonder what's attracting them."
"I don't know," the other said. "They must have a butterfly bush, maybe?"
"Oh, that's probably it. A butterfly bush."
Well, what's attracting them is the Passiflora, the host plant of the Gulf Frits. It's a congregation without a church. It's a gathering without a sermon. It's Nature at its finest. The Gulf Frits, aka "passion butterflies," lay their eggs only on the passionflower vine--mostly on the tendrils or leaves. The caterpillars will eat only Passiflora. The adults? They'll nectar on such plants as the butterfly bush, Mexican sunflower and lantana but will stay close to the Passiflora for mating and egg-laying.
If you're lucky, you'll see the entire life cycle--from egg to caterpillar to chrysalis to adult.
If you're really lucky, you'll see the tiny yellow eggs, which are about the size of the period at the end of this sentence. The yellow eggs turn from orange to rust, the color of the caterpillar inside.
The butterfly, found in many parts of the world, is a relatively newcomer to California. It was documented in Southern California, in the San Diego area, in the 1870s, according to butterfly guru Art Shapiro, distinguished professor of evolution and ecology at UC Davis. “It spread through Southern California in urban settings and was first recorded in the Bay Area about 1908. It became a persistent breeding resident in the East and South Bay in the 1950s and has been there since.”
Shapiro says it “apparently bred in the Sacramento area and possibly in Davis in the 1960s, becoming extinct in the early 1970s, then recolonizing again throughout the area since 2000.”
Today I explored the unseen and intricate world of Gulf Frits in our Vacaville (Solano County) backyard, managing to capture a few images. Then the unexpected happened. For the first time in the five years we've been rearing Gulf Frits, one landed on me! Apparently mistaking me for a plant, she touched down on my green t-shirt (which probably carried the scent of the passionflower vine). She was all set to lay an egg until....two males approached. Startled and a bit rattled--hey, I'm laying an egg here, leave me alone!--off she flew.
This time she vanished inside the depths of the passionflower vine.
With any luck, she'll do just fine in this congregation without a church, in this gathering without a sermon. She'll provide another generation that resembles the striking colors of those stained glass windows in a religious sanctuary.
Splat! Splat! Splat! What was that?
A squadron of flying insects? No, more like multiple squadrons of flying insects.
There's a major outbreak in the area of alfalfa butterflies, also known as sulphur butterflies, Colias eurytheme.
Art Shapiro, UC Davis distinguished professor of evolution and ecology who has monitored butterflies in Central California for more than 40 years and posts information on his website, says he's been receiving lots of inquiries about the sulphur butterfly outbreak. Their caterpillars are major pests of alfalfa. The 'cats can consume an entire alfalfa leaf, including the midrib.
"Outbreaks like this used to be commonplace in late summer and fall in the Valley," Shapiro says, "but they disappeared during the drought: from 2012 through 2015 there were hardly any Colias, and I even contacted ranchers and farm advisers to find out if they were using any new pesticides or had altered alfalfa culture in some way that might account for the situation." The answer: No.
"The last big outbreak around here (Davis) was in October 2012," the professor noted. "Long-time residents can recall killing multitudes of them when driving near alfalfa fields in the Valley back in the 'old days.' Now it's happening again! Mass dispersal, like we're seeing now--when they blanket urban flower gardens and mowed lawns--typically occurs when the alfalfa is cut. Females are laying eggs on clover in lawns. One is, of course, tempted to say it must somehow be related to the weather--but we really don't know."
Encounters with cars and people and--yes, predators--continue. We just noticed an alfalfa butterfly trapped in a spider web in our yard.
There will be more.
UC Statewide Integrated Pest Program: Alfalfa Butterfly
- You want to do your part to help the declining bee population.
- You want to learn about the honey bees that pollinate the food you eat, including fruits, vegetables and nuts (especially almonds!).
- You'd love some honey for your table and some wax to make candles.
- You want to learn about the queen bee, drones and worker bees--what they do and how to care for them.
- You want to join your fellow beekeeping friends.
But where do you start?
You're in luck.
The E. L. Nino lab at the University of California, Davis, is offering two back-to-back short courses: the first on Saturday, Aug. 27 on “Planning Ahead for Your First Hives” and the second on Sunday, Aug. 28 on “Working Your Colonies.”
Each will take place from 9 a.m. to 5 p.m. in the Harry H. Laidlaw Jr. Honey Bee Research Facility, located on Bee Biology Road, west of the central campus.
Participants may register for one or both courses, according to Extension apiculturist Elina Niño, who is coordinating and teaching the courses with Bernardo Niño and colleagues at the Laidlaw facility. The short courses will be limited to 25 people.
Here's some information about each:
Planning Ahead for Your First Hive
The course, “Planning Ahead for Your First Hives,” taught by Elina Niño, Bernardo Niño, Charley Nye and Tricia Bohls, will provide lectures and hands-on exercises. The course is described as “perfect for those who have little or no beekeeping experience and would like to obtain more knowledge and practical skills before moving on to the next step of owning and caring for their own honey bee colonies.”
Lecture modules will cover honey bee biology, beekeeping equipment, how to start your colony, and maladies of the hive. Practical modules will zero in on how to build a hive, install a package, inspect a hive and monitor for varroa mites.
Participants will have the opportunity to learn about and practice many aspects of what is necessary to get the colony started and keep it healthy and thriving. At the end of the course, participants "will be knowledgeable about installing honey bee packages, monitoring their own colonies and taking on possible challenges with maintaining a healthy colony."
The $95 registration fee covers the cost of course materials (including a hive tool), lunch and refreshments.
Working Your Colonies
For the short course, “Working Your Colonies,” instructors are Elina Niño and Bernardo Niño. The course, to include lectures and hands-on exercises, is described as “perfect or those who already have beekeeping experience and would like to obtain more knowledge and practical to move on to the next step of managing and working their own honey bee colonies.”
Lecture modules will include advanced honey bee biology, honey bee integrated pest management and products of the hive. Practical modules will cover queen wrangling, honey extraction, combining colonies, splitting colonies and monitoring for varroa mites. The $150 registration fee covers the cost of course materials, lunch, and refreshments.
For each course, participants are asked to bring a bee suit or veil if they have one (the lab has a limited number). Lodging is not provided. For more information on registering for the short courses, contact Bernardo Niño at firstname.lastname@example.org or (530) 380-BUZZ (2899). Want to access up-to-date information? See lab's Facebook page.
In a groundbreaking discovery, a scientific team of Brazilians and Brazilian-born chemical ecologist Walter Leal of the University of California, Davis, has announced that the Zika virus has been detected in wild-caught Culex quinquefasciatus mosquitoes in Recife, the epicenter of the Zika epidemic.
Scientists from the Fiocruz Institute, Pernambuco, confirmed the discovery July 21. The detection could have widespread repercussions, as the Culex mosquitoes are more common and widespread than the yellow fever mosquito, Aedes aegypti, known as the primary carrier of the Zika virus.
Leal, who collaborates with Fiocruz Institute researcher Constancia Ayres in a National Institutes of Health-sponsored project on the investigation of Zika in the C. quinquefasciatus, said that the Brazilian lab earlier discovered that Culex had the capability of transmitting the virus. Although the scientists were able to infect the lab mosquitoes with the virus, they had not found the virus in wild-caught mosquitoes—until now.
“This could have major repercussions here in the United States and in other parts of the world,” said Leal, a distinguished professor in the UC Davis Department of Molecular and Cellular Biology who is co-chairing the International Congress of Entomology meeting Sept. 25-30 in Orlando, Fla. The conference is expected to draw some 7000 entomologists throughout the world.
Leal said more work needs to be done to see if Culex mosquitoes are playing a role in the current epidemic. In an interview July 21 with health reporter Jennifer Yang of the Toronto Star, Canada's largest daily, he commented: “It looks like there were more vectors than we thought, and this is one of them. We don't have to panic, but we have to know. And now that we know, we have to take care of the Culex.”
A. aegypti is already established in California; it has spread to at least seven counties since its discovery in Clovis, Fresno County, in June 2013, according to medical entomologist Anthony Cornel of the UC Davis Department of Entomology and Nematology and the UC Kearney Agricultural Research and Extension Center, Parlier.
The Zika virus, which can result in birth defects in pregnancy, can be transmitted through exposure to infected blood or sexual contact. The Centers for Disease Control estimates that between 400,000 and 1.3 million cases have been discovered across South, Central, and North America, where the disease was previously unknown.
Leal and a group of 18 students just hosted a Zika Public Awareness Symposium on May 26 at Giedt Hall, UC Davis campus. The podcast can be accessed at https://video.ucdavis.edu/media/Zika+Virus+Public+Awareness+Symposium/0_n3aupf5c