We missed it, too. So did the ants and other insects.
The Department of Entomology and Nematology annually hosts dozens of popular Picnic Day events at Briggs Hall and at the Bohart Museum of Entomology. But this year, due to the coronavirus pandemic, “closed” was the word of the day.
"Closed." It's not a popular word when you're craving to show your audience the wonderful world of insects.
However, this year the campuswide Picnic Day Committee hosted a virtual tour of some of the planned events, and posted this link: https://picnicday.ucdavis.edu/virtual/
The spotlight paused on the Bohart Museum, which houses nearly eight million insect specimens; the seventh largest insect collection in North America; the California Insect Survey, a storehouse of the insect biodiversity; and a live “petting zoo” comprised of Madagascar hissing cockroaches, walking sticks, tarantulas and the like. It also is the home of a gift shop, stocked with T-shirts, sweatshirts, books, jewelry, posters, insect-collecting equipment and insect-themed candy.
Directed by UC Davis entomology professor Lynn Kimsey for 30 years, the museum is named for noted entomologist Richard Bohart (1913-2007). The Bohart team includes senior museum scientist Steve Heydon; Tabatha Yang, education and outreach coordinator; and entomologist Jeff Smith, who curates the Lepidoptera (butterflies and moths section).
If you browse the Bohart Museum site, you'll find fact sheets about insects, written by Professor Kimsey.
But if you want to see the Bohart Museum's virtual tours, be sure to watch these videos:
- Director Lynn Kimsey giving a Bohart Museum introduction
- Tabatha Yang, education and outreach coordinator, presenting an arthropod virtual tour
- Diane Ullman, professor of entomology and former chair of the department, presenting a view of the Lepidodpera section.
Also on the UC Davis Virtual Picnic Day site, you'll learn “How to Make an Insect Collection," thanks to project coordinator James R. Carey, distinguished professor, UC Davis Department of Entomology and Nematology; and "Can Plants Talk to Each Other?" a TED-Ed Talk featuring the work of ecologist Rick Karban, professor, UC Davis Department of Entomology and Nematology.
Other research work that draws widespread attention at the annual UC Davis Picnic Day is the work of UC Davis medical entomologist-geneticist Geoffrey Attardo, assistant professor of entomology. A global authority on tsetse flies, he specializes in reproductive physiology and molecular biology, in addition to medical entomology and genetics.
"Female tsetse flies carry their young in an adapted uterus for the entirety of their immature development and provide their complete nutritional requirements via the synthesis and secretion of a milk like substance," he says. PBS featured his work in its Deep Look video, “A Tsetse Fly Births One Enormous Milk-Fed Baby,” released Jan. 28, 2020. (See its accompanying news story.)
PBS also collaborated with the Attardo lab and the Chris Barker lab, UC Davis School of Veterinary Medicine, for a PBS Deep Look video on Aedes aegypti, the mosquito that transmits dengue fever and Zika. The eggs are hardy; "they can dry out, but remain alive for months, waiting for a little water so they can hatch into squiggly larvae," according to the introduction. Watch the video, "This Dangerous Mosquito Lays Her Armored Eggs--in Your House."
In the meantime, the UC Davis Picnic Day leaders are gearing up for the 106th annual, set for April 17, 2021. What's a picnic without insects?
A recent article in Science headlined "Once Considered Outlandish, the Idea that Plants Help their Relatives Is Taking Root," and dealing with how plants communicate, is drawing widespread attention.
Wrote Elizabeth Pennisi: "For people, and many other animals, family matters. Consider how many jobs go to relatives. Or how an ant will ruthlessly attack intruder ants but rescue injured, closely related nestmates. There are good evolutionary reasons to aid relatives, after all. Now, it seems, family feelings may stir in plants as well."
"A Canadian biologist planted the seed of the idea more than a decade ago, but many plant biologists regarded it as heretical—plants lack the nervous systems that enable animals to recognize kin, so how can they know their relatives? But with a series of recent findings, the notion that plants really do care for their most genetically close peers—in a quiet, plant-y way—is taking root. Some species constrain how far their roots spread, others change how many flowers they produce, and a few tilt or shift their leaves to minimize shading of neighboring plants, favoring related individuals."
Pennisi quoted ecologist Richard "Rick" Karban, professor in the UC Davis Department of Entomology and Nematology, for her piece. An international authority on plant communication, he authored the 240-page book, Plant Sensing and Communication (University of Chicago Press), considered a landmark in its field.
An excerpt from Science: "Sagebrush bushes (Artemisia tridentata) have provided some strong clues, however. When injured by herbivores, these plants release volatile chemicals that stimulate neighboring sagebrush to make chemicals toxic to their shared enemies. Ecologist Richard Karban at the University of California, Davis, wondered whether kin were preferentially warned. His group had already found that sagebrush plants roughly fall into two "chemotypes," which mainly emit either camphor or another organic compound called thujone when their leaves are damaged. The team showed that the chemotypes are heritable, making them a potential kin recognition signal. In 2014, the researchers reported that when volatiles from a plant of one chemotype were applied to the same type of plant, those plants mounted stronger antiherbivore defenses and had much less insect damage than when the volatiles were applied to a plant of the other chemotype—a hint of a kin effect."
She concluded with a quote from Karban: "We are learning that plants are capable of so much more sophisticated behavior than we had thought. It's really cool stuff."
"We aren't actually doing more work that addresses the issue of kin recognition," Karban told us. "We have found that sagebrush plants communicate more effectively with kin than strangers and more effectively with other individuals that belong to the same 'chemotype' as they do. Chemotypes are similar to blood types - they represent chemical variation among individuals in the population. As with blood types, it is puzzling why this variation exists. The cues that sagebrush use to communicate are potentially extremely complex; we can identify on the order of 100 volatile compounds that are emitted by damaged foliage. This gives an enormous number of possible 'words' that could provide information in the 'language' that the plants may be using. Since the chemotypes differ in only a few compounds, we are hoping that focusing on chemotypic variation will provide some clues that help us begin to decipher the language of the plants.
Karban has researched plant communication in Artemisia tridentataon the east side of the Sierra since 1995. His groundbreaking research on plant communication among kin, published in February 2013 in the Proceedings of the Royal Society B: Biological Sciences, drew international attention. In that study, Karban and his co-researchers found that kin have distinct advantages when it comes to plant communication, just as “the ability of many animals to recognize kin has allowed them to evolve diverse cooperative behaviors.”
“Plants responded more effectively to volatile cues from close relatives than from distant relatives in all four experiments and communication reduced levels of leaf damage experienced over the three growing seasons,” Karban wrote.
The gist of it: if you're a sagebrush and a predator (such as a grasshopper) is eating your nearby kin, another sagebrush, it's good to be closely related. Through volatile (chemical) cues, your kin will inform you of the danger so you can adjust your defenses. Yes, plants can communicate.
We remember asking Karban several years go "the 10 things to know about plant sensing and communication." According to Karban:
- Plants sense their environments and respond.
- Although they lack central nervous systems, they process information and appear to "behave intelligently."
- They sense the position of competitors and "forage" for light.
- They sense the availability of water and nutrients in the soil and "forage" for these resources.
- Their decisions are influenced by past experiences, akin to memory.
- They respond to reliable cues that predict future events, allowing them to "anticipate."
- Plants respond differently to cues that they themselves produce, allowing them to distinguish self from non-self.
- They respond differently to close relatives and strangers.
- Plants that are prevented from sensing or responding experience reduced fitness.
- By understanding the "language" of plant responses, we can grow healthier and more productive plants.
The most basic form of communication? When a plant is being shaded, it senses the diminished light quality caused by a competitor and responds by moving away, Karban says.
Karban's work on plant communication is featured in a 2016 interactive lesson plan, TED-Ed Original Lessons where "words and ideas of educators are brought to life by professional animators.” Plants can eavesdrop, sense danger in the environment, and can distinguish friend from foe, he says.
They can also do something else.
Basically, if you're a plant and an insect is attacking you, you can communicate your stress to nearby plants as a way to alert them about potential danger--very similar to how animals communicate or respond to predators, according to UC Davis agricultural entomologist Christian Nansen of the Department of Entomology and Nematology.
In groundbreaking research published in the journal Plant Methods, Nansen and his team of six colleagues from Brazil discovered that plant-plant communication causes physiological changes in plants and these subtle changes can be detected via analyses of leaf reflectance or hyperspectral imaging. The article is titled “Hyperspectral Imaging to Characterize Plant-Plant Communication in Response to Insect Herbivory."
The growing knowledge about plant-plant communication and about plants' ability to assess their environment has led to concepts like “plant neuro-biology” and “plant behavior,” said Nansen, an associate professor who centers his research on host plant-stress detection, host selection by arthropods, pesticide performance, and use of reflectance-based imaging in a wide range of research applications.
“We know that plants don't have a neural system or brain,” said Nansen, “but respected scientists are studying plants as if they did, as if plants are able to assess conditions in their environments, and they can adapt/respond to those conditions.”
“In studies of plant stress signaling, a major challenge is the lack of non-invasive methods to detect physiological plant responses and to characterize plant-plant communication over time and space.” Nansen pointed out. He described the research as “initial evidence of how hyperspectral imaging may be considered a powerful non-invasive method to increase our current understanding of both direct plant responses to biotic stressors but also to the multiple ways plant communities are able to communicate.”
The UC Davis entomologist and his team used leaf reflectance data to detect and characterize plant responses to stressors, knowing that induced stress interferes with photosynthesis, chemical composition and physical structure of the plant, thus affecting the absorption of light energy and altering the reflectance spectrum of the plants.
“For several decades, it has been known that plants communicate – both among individuals of the same species and across species,” Nansen related. “That is, volatiles emitted by one plant can be received by another plant and trigger different physiological responses. It is also well-documented that plants communicate via roots, and sometimes the roots from different plants are brought together in a network of communication and exchange of nutrients through symbioses with mychorriza (soil fungi).”
Of the Nansen study, Karban said: "This study describes a technique that may provide a relatively quick and inexpensive way to evaluate levels of resistance in plants. If these results are repeatable by other workers in other systems, they will provide a very valuable tool for researchers and growers."
Both Karban and Nansen contributed chapters to the recently published book, The Language of Plants (University of Minnesota Press). The book explores "the idea that plants can think, feel, and communicate as a way of reconfiguring our relationship with the natural world," according to editors Monica Gagliano, John C. Ryan, and Patrícia Vieira.
"Within the last decade or so, extremely cutting-edge research in the field of plant-plant communication has been done by people like Dr. Monica Gagliano of the University of Western Australia," Nansen said. "She has elegantly demonstrated that plants can respond not only to aerial volatile compounds and root secretions but also to sound."
For the research project, Nansen and his team decided to conduct “a very simple experiment with corn plants and stink bugs.” They planted corn plants in separate pots or two in one pot. They subjected some plants to herbivory by stink bugs, while other plants served as control plants.
The scientists collected two types of data: phytocompounds (stress hormones and pigments) and leaf reflectance data (proximal remote sensing data).
“Our research hypothesis was that insect herbivory causes changes in leaf phytocompound levels, and these physiological defense responses are associated with detectable changes in phytocompound levels and in certain spectral bands of leaf reflectance profiles,” Nansen pointed out. As a secondary hypothesis, the researchers predicted that plant-plant communication (from plant with herbivory to an adjacent control plant without herbivory) will elicit both a change in phytocompound composition of leaves and also cause a corresponding change in leaf reflectance.
The result: The first published study, in which comprehensive phytocompound data have been shown to correlate with leaf reflectance. In addition, it is the first published study of leaf reflectance in plant-plant communication.
Nansen and co-author Leandro do Prado Ribeiro of the Research Center for Family Agriculture, Research and Rural Extension Company of Santa Catarina, Brazil, conceived and designed the experiments. The Brazilian National Counsel of Technological and Scientific Development provided partial financial support. Co-author Marilia Almeida Trapp received financial support from a Capes-Humboldt Research Fellowship.
We just received word that noted ecologist Richard “Rick” Karban, professor in the UC Davis Department of Entomology and Nematology, has been named a fellow of the Ecological Society of America (ESA) for “his innovative contributions to community and evolutionary ecology, especially through providing conceptual advances and rigorous experimental work on plant-insect interactions."
Karban, an international authority on plant communication, is the "go-to" person when folks want a news story about plant communication or when scientists want to research plant sensing and communication.
“Rick's pioneering discoveries on plant communication through volatile compounds certainly merit this recognition,” said Steve Nadler, professor and chair of the UC Davis Department of Entomology and Nematology.
Karban authored the 240-page book, Plant Sensing and Communication (University of Chicago Press), considered a landmark in its field.
ESA, in announcing its list of 27 fellows today (Feb. 6), said that its fellowship program recognizes the many ways in which its members contribute to ecological research and discovery, communication, education and pedagogy, and management and policy.
“Plants responded more effectively to volatile cues from close relatives than from distant relatives in all four experiments and communication reduced levels of leaf damage experienced over the three growing seasons,” they wrote.
The gist of it: if you're a sagebrush and a predator (such as a grasshopper) is eating your nearby kin, another sagebrush, it's good to be closely related. Through volatile (chemical) cues, your kin will inform you of the danger so you can adjust your defenses. Yes, plants can communicate
Karban was featured in a December 2013 edition of The New Yorker in Michael Pollan's piece, “The Intelligent Plant: Scientists Debate a New Way of Understanding Plants."
Karban and his graduate student, Eric Lopresti, also drew widespread interest when they announced that their woolly bear caterpillars can predict whether a Republican or Democrat will be elected to the White House. When the population of woolly bear caterpillars (Ranchman's Tiger Moth, Platyprepia virginalis) at their research site at the Bodega Marine Reserve thrives, a Democrat heads to the White House, they said. When the population dives (as it did this year), a Republican occupies the oval office. (See Bug Squad blog).
And why not? “Paul the Octopus had a pretty good run predicting soccer matches in 2012, so perhaps the woolly bears have earned as much credibility at forecasting this presidential election,” Karban related. Who says scientists don't have fun?
Highly honored by his peers, Karban is a fellow of the American Association for the Advancement of Science (AAAS) and recipient of the 1990 George Mercer Award from ESA for outstanding research. He was named an outstanding professor, ecology, at UC Davis in 1986. He has published three books and more than 100 journal articles.
Karban received his bachelor's degree in environmental studies from Haverford (Penn.) College in 1977 and his doctorate in biology from the University of Pennsylvania, Philadelphia, in 1982. He joined the UC Davis faculty in May 1982 as an assistant professor, advancing to associate professor in 1988 and to full professor in 1994.
Overall, it was a great day today for UC Davis ecologists. Also selected fellows were:
- Anurag Agrawal, professor in the Department of Ecology and Evolutionary Biology, Cornell University, who received his doctorate at entomology at UC Davis in 1999, studying with Rick Karban. Agrawal was singled out his “innovative contributions to community and evolutionary ecology, especially through providing conceptual advances and rigorous experimental work on plant-insect interactions.”
- John Stachowicz, professor of evolution and ecology, of the UC Davis Department of Evolution and Ecology “for his fundamental contributions to the fields of symbiosis andmutualism,multi-trophic species interactions,biogeography, and invasion biology.”
ESA established its fellows program in 2012 with the goal of honoring its members and supporting their competitiveness and advancement to leadership positions in the Society, at their institutions, and in broader society, said spokesperson Lisa Lester.
The 10,000-member Ecological Society of America, founded in 1915, is the world's largest community of professional ecologists. They're committed to advancing the understanding of life on Earth, and some 4000 attend the Annual Meeting, featuring the most recent advances in ecological science. The Society publishes five journals and a membership bulletin and broadly shares ecological information through policy, media outreach, and education initiatives.
For the past three decades, woolly bear caterpillars have accurately predicted a Republican or Democrat win in the U.S. Presidential elections.
This year, despite the pollsters, pundits and political fervor, the woollies again successfully predicted the outcome.
Just as noted UC Davis ecologist Richard “Rick” Karban and his lab prognosticated.
Karban and his fifth-year doctoral student, Eric LoPresti, study the woolly bear caterpillars, which populate the cliffs of the Bodega Marine Reserve, above the Bodega Marine Laboratory, Sonoma County. The fuzzy reddish-black caterpillars, which feed primarily on lupine, are the immature form of the Ranchman's Tiger Moth, Platyprepia virginalis.
Sometimes the population booms; other times, it's a bust, said Karban, a professor in the UC Davis Department of Entomology and Nematology and a fellow of the American Association for the Advancement of Science. In their 30-year census of the same lupine patch, they noticed that when the population thrives, a Democrat heads to the White House. When the population dives, the Republicans take over.
And why not? “Paul the Octopus had a pretty good run predicting soccer matches in 2012, so perhaps the woolly bears have earned as much credibility at forecasting this presidential election,” Karban said last May.
Although most polls forecast a Democratic win, the UC Davis Woolly Bear Presidential Election Outlook did not.
However, they are not all that pleased with the outcome. “We're kind of bummed,” Karban said. “We didn't want to believe that the woolly bears were predicting a red outcome.”
The scientists, who study insect-plant interactions, first announced their presidential outcome predictions in a poster displayed at the 2014 Ecology Society of America meeting, held in Sacramento. Then this year, on April 25, they expanded on the concept, complete with intricate charts plotted in red and blue, in LoPresti's Natural Musings blog, “The Woolly Bear Presidential Election Outlook 2016,” co-written by scientists in the Karban lab.
“Each March, Karban censuses the same patches of lupine that he has for over 30 years,” LoPresti explained in Natural Musings. “The study asks a vexing question: Why are there are so many caterpillars in some years and so few in others? Many insects, including pests cycle like this, therefore it is of keen interest to many. Dozens of papers later, Karban, his students, and his collaborators have answered a great many questions, including how caterpillars deal with parasites, whether population cycles are influenced by rain, whether caterpillars enjoy eating plant hairs, and how caterpillars avoid their predators.”
The woolly bears, as presidential forecasters, drew national attention. Washington Post reporter Karin Bruilliard ran with it in a piece published April 26: “These Fuzzy Little Caterpillars Are Better at Predicting Elections Than Most Pundits.”
“Who's going to win the presidential election?” Bruilliard asked. “Heck if we know. Try to answer that question without a crystal ball and you'll run head-on into a dizzying array of national polls and state polls, fundraising tables and delegate counts, endorsements and prediction markets.”
LoPresti posted in his Natural Musings blog on April 25 that the woollies “seem to be leaning Republican.”
“Given their (pollsters') wildly erroneous predictions thus far for both primaries, trusting their predictions for the general election seems ill-advised,” LoPresti wrote. “The woolly bears, on the other hand, have a 100% accurate prediction record over the past 30 years. In years of low abundance, a Republican is elected, and in years of high abundance, a Democrat.”
“A superficial examination suggests that 2016 will be a Republican year – woolly bear abundance is not particularly high,” LoPresti noted. “However, looking a little closer, it may not be. The number of woolly bears per lupine bush in 2016 (0.53) is higher than the average Republican year by 152% and is 36% above the highest Republican year ever recorded (1988). However, it is only 27% of an average Democratic year and still only 36% of the lowest Democratic year (2008). This result is without presidential precedent in the last 30 years.”
What about the next presidential election, now that Vice President Joe Biden has indicated he might run?
“The woolly bears have not weighed in on Joe Biden,” Karban said.
Karban, internationally known for his work on plant communication, is the author of the book, Plant Sensing and Communication (University of Chicago Press), hailed as a landmark in its field. He has researched plant communication in sagebrush (Artemisia tridentata) on the east side of the Sierra since 1995.
Plants can eavesdrop, sense danger in the environment, and can distinguish friend from foe, Karban says. A plant under a predatory attack will emit volatile chemical cues, enabling its neighboring plants to adjust their defenses to better protect themselves.
Karban is featured in the Dec. 23-30, 2013 edition of The New Yorker in Michael Pollan's piece, “The Intelligent Plant: Scientists Debate a New Way of Understanding Plants."