- Author: Kathy Keatley Garvey
The Republicans tout their elephants. The Democrats, their donkeys. But UC Davis ecologists believe that their “bears” will successfully predict which political animal will win the U.S. presidential election, as they've done for the past three decades.
Bears? That would be the woolly bear caterpillars, the immature form of the Ranchman's Tiger Moth, Platyprepia virginalis.
Professor Richard “Rick” Karban of the UC Davis Department of Entomology and Nematology and his graduate students study the woolly bear caterpillars that dine primarily on lupine along the cliffs of Bodega Bay. Sometimes the population booms; other times, it's a bust. When the population thrives, a Democrat heads to the White House. When the population dives, the Republicans take over.
The UC Davis scientists, known for their expertise in plant-insect interactions, are now drawing national headlines for their presidential predictions.
“The pollsters and talking heads seem unable to size up this election cycle,” said Karban. “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.”
The scientists first announced their findings in a poster displayed at the 2014 Ecology Society of America meeting. 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.
Washington Post reporter Karin Bruilliard picked it up and ran with it on April 26 in a piece titled, “These Fuzzy Little Caterpillars Are Better at Predicting Elections Than Most Pundits.”
“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.”
“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.”
So, which party, aka political animal, will occupy the White House come Jan. 1, 2017?
“We suspect that the Republicans have the edge,” the UC Davis scientists surmised. “However, a valid hypothesis would be a third-party winner, such as a right-leaning independent (a logical placeholder in between Democrats and Republicans). Perhaps Donald Trump will take particular interest in our data. Alternately, a contested Republican convention could produce a fractured party and the old Republican woolly bear average would not accurately represent the mean caterpillar abundances seen by this new party.”
Responding to the April 25 blog, someone noticed the resemblance of the hair of a presidential candidate to the hair of the woolly bear caterpillar.
The UC Davis scientists study the caterpillars at the Bodega Marine Reserve above the Bodega Marine Laboratory. The reserve, which surrounds the Bodega Marine Laboratory, is a unit of the University of California Natural Reserve System and is administered by UC Davis.
“Platyprepia virginalis caterpillars are dietary generalists and feed on multiple host species within a single day,” Karban says.
In research, Diet Mixing Enhances the Performance of a Generalist Caterpillar, Platyprepia virginalis, published in February 2010 in the journal Ecological Entomology, “We found that relative growth rates and rates of survival were higher when they fed on mixed diets compared to lupine only,” Karban said. These results were consistent with hypotheses that mixed diets provided balanced nutrition, diluted toxins, and/or allowed recovery from parasitoids, although our data did not allow us to separate these non-exclusive explanations.”
The caterpillar's taste for plants containing alkaloids may help it survive parasitoids, Karban said.
- Author: Kathy Keatley Garvey
Now UC Davis researchers have found that some plants excrete a stickylike glue to entrap sand so predators won't eat them.
Graduate student Eric LoPresti and his major professor, ecologist Rick Karban, professor in the UC Davis Department of Entomology and Nematology, found that two plants, sand verbena Abronia latifolia and the honeyscented pincushion plant Navarretia mellita appear to deliberately make themselves unappealing with a coat of “sand armor.”
Sand entrapment on plant surfaces is called psammophory or sand armor, they said in newly published research in the journal Ecology.
Thus, herbivores like rabbits and bison, avoid eating them. “Sand and soil are nonnutritive and difficult for herbivores to process, as well as visually identical to the background,” they wrote in their abstract.
LoPresti and Karban set out to investigate whether the sand-coating serves as a camouflage or a shield from predators or both.
“We experimentally investigated whether this sand coating physically protected the plant from herbivores or increased crypsis (or the ability of an animal to avoid observation or detection),” they said. “We tested the former hypothesis by removing entrapped sand from stems, petioles, and leaves of the sand verbena Abronia latifolia and by supplementing natural sand levels in the honeyscented pincushion plant Navarretia mellita. Consistent with a physical defensive function, leaves with sand present or supplemented suffered less chewing herbivory than those with sand removed or left as is.”
They tested the “possible crypsis effect” by coating some sand verbena stems with green sand, matching the stem color, as well as others with brown sand to match the background color. “Both suffered less chewing herbivory than controls with no sand and herbivory did not significantly differ between the colors, suggesting crypsis was not the driving resistance mechanism.”
Since their paper's online publication, the work has been featured in Newsweek, Discover and on CBC Radio.
Links:
- Author: Kathy Keatley Garvey
So says ecologist Richard Karban, professor of entomology in the UC Davis Department of Entomology and Nematology, in his newly published book, Plant Sensing and Communication (University of Chicago Press).
The 240-page book is a “landmark in its field,” said Graeme Ruxton of the University of St. Andrews, UK, co-author of Experimental Design for the Life Sciences and Plant-Animal Communication.
The book is “the first comprehensive overview of what is known about how plants perceive their environments, communicate those perceptions, and learn,” according to the publisher. “Facing many of the same challenges as animals, plants have developed many similar capabilities: they sense light, chemicals, mechanical stimulation, temperature, electricity, and sound. Moreover, prior experiences have lasting impacts on sensitivity and response to cues; plants, in essence, have memory."
Added the publisher: “Nor are their senses limited to the processes of an individual plant: plants eavesdrop on the cues and behaviors of neighbors and—for example, through flowers and fruits—exchange information with other types of organisms. Far from inanimate organisms limited by their stationary existence, plants, this book makes unquestionably clear, are in constant and lively discourse.”
What are 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.
- The 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.
Karban has researched plant communication in sagebrush (Artemisia tridentata) on 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,” they wrote.
In other words, if you're a sagebrush and your nearby kin is being eaten by a grasshopper, deer, jackrabbit, caterpillar or other predator, communication is more effective if you're closely related. Through volatile cues, your kin will inform you of the danger so you can adjust your defenses.
Karban likened this kind of plant communication to eavesdropping.” Plants “hear” the volatile cues of their neighbors as predators damage them.
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.
“Plants are smart,” wrote Adrian Barnett of New Scientist in reviewing the book. “But to notice we have to overcome our ingrained cultural biases. . . . Clearly, we will never play chess with a rose, nor ask the orchid on our windowsill for advice. But that is the point: humans are guilty of serious parochialism, of defining intelligence in terms of a nervous system and muscle-based speed that enables things to be done fast…Plants are highly responsive, attuned to gravity, grains of sand, sunlight, starlight, the footfalls of tiny insects, and to slow rhythms outside our range. They are subtle, aware, strategic beings whose lives involve an environmental sensitivity very distant from the simple flower and seed factories of popular imagination.”
Barnett praised Karban's book as a “timely, highly accessible summary of fast-developing fields.”
Karban is a fellow of the American Association for the Advancement of Science (AAAS) and has published more than 100 journal articles and now, three books.
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."
Related Link:
Rick Karban: Kin Recognition Affects Plant Communication and Defense
- Author: Kathy Keatley Garvey
This is a meeting of the Davis Botanical Society, which begins at 6:45 p.m. President Marie Jasieniuk will announce the 2014 student grant recipients and the members will elect new officers. All interested persons are invited. The library is located at 315 E. 14th St.
Karban will discuss the rarely studied phenomenon of communication between plants, announced plant taxonomist Ellen Dean, curator, Center for Plant Diversity. "For a number of years, Dr. Karban has been studying plant-to-plant communication in big sagebrush (Artemisa tridentata) at Sagehen Creek in the Sierrra Nevada. His research has shown that volatile compounds are released from injured plants and that these compounds are detected by nearby plants, allowing them to better defend themselves against herbivores and other predators."
Excerpts from a news release published Feb. 13, 2013 by the UC Davis Department of Entomology and Nematology:
If you're a sagebrush and your nearby kin is being eaten by a grasshopper, deer, jackrabbit, caterpillar or other predator, 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.
If you're not closely related, communication won't be as effective.
Newly published research in today's Proceedings of the Royal Society B: Biological Sciences shows 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,” says lead researcher and ecologist Richard Karban, a professor in the UC Davis Department of Entomology.
For example, fire ants can recognize kin. “Ants will destroy queens that are not relatives but protect those who are,” Karban said.
That ability is less well studied for plants, until now.
“When sagebrush plants are damaged by their herbivores, they emit volatiles that cause their neighbors to adjust their defenses,” Karban said. “These adjustments reduce rates of damage and increase growth and survival of the neighbors.” See more.
- Author: Kathy Keatley Garvey
Karban, who studies volatile (chemical) communication between plants that affect their defenses against herbivores, will speak from 8:10 to 8:45. He is one of four speakers booked from 7 to 9 p.m.
The event, free and open to the public, begins at 6:30 with socializing and networking. It is sponsored by the UC Davis Art/Science Fusion Program.
Other speakers are
- Tami Spector, a professor of organic chemistry at the University of San Francisco, whose topic is “The Molecular Elusive”
- Katharine Hawthorne, a San Francisco-based dancer and choreographer, “Analog Bodies” and
- Cody Ross, a postdoctoral cultural and statistical anthropologist working at the Santa Fe Institute and UC Davis. “Art Is Offensive: Integrative Art and Social Justice.”
Karban drew international scientific and media attention with his research on “Kin Recognition Affects Plant Communication and Defense,” published in February 2013 in the Proceedings of the Royal Society B: Biological Sciences. He and four colleagues showed 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,” he told the UC Davis Department of Entomology and Nematology in a news release.
“When sagebrush plants are damaged by their herbivores, they emit volatiles that cause their neighbors to adjust their defenses,” Karban said. “These adjustments reduce rates of damage and increase growth and survival of the neighbors.”
Karban was featured in Michael Pollan's piece on “The Intelligent Plant: Scientists Debate a New Way of Understanding Plants,” published last December in The New Yorker.” He is also spotlighted on YouTube.
A member of the UC Davis Department of Entomology and Nematology since 1982, Karban received his bachelor's degree in environmental studies from Haverford (Pa.) College, and his doctorate in biology from the University of Pennsylvania, Philadelphia.
He is a fellow of the American Association for the Advancement of Science (AAAS) and has published more than 100 journal articles and two books.
Brief biographies:
Tami Spector, professor of organic chemistry at the University of San Francisco, will speak from 7 to 7:25 p.m. on “The Molecular Elusive.” She was trained as a physical organic chemist. Her scientific work has focused on fluorocarbons, strained ring organics, and the molecular dynamics and free energy calculations of biomolecules. Spector also has a strong interest in aesthetics and chemistry and has published and presented work on molecular and nano- aesthetics, the visual image of chemistry, and the relationship between chemistry and contemporary visual art. She serves on the governing and editorial boards of Leonardo/ISAST, co-hosts the San Francisco based Leonardo Arts Sciences Evening Rendezvous' (LASERs), and serves as the co-editor of an ongoing special section “Art and Atoms” for Leonardo Journal.
Katharine Hawthorne, a San Francisco based dancer and choreographer who makes live performances about thinking bodies in motion, will speak on “Analog Bodies” from 7:25 to 7:50. “How can analog signals and old technologies can be used as metaphors for understanding the body, and in
Cody Ross, now a postdoctoral cultural and statistical anthropologist working at the Santa Fe Institute and UC Davis, will speak on “Art Is Offensive: Integrative Art and Social Justice” from 8:40 to 9 p.m.
Ross works on projects concerning intergenerational wealth transmission and the persistence of economic inequality. His work, both academic and artistic, is targeted toward inspiring deeper discourse about issues related to social justice.
“This talk focuses on the intersection of Art (subjective) and Science (objective), with Activism/Justice/Justness (intersubjective),” Ross says in his abstract. “We use several of my own art pieces and performances to think through the ways in which integrative, socially, conscious art can provide a way of representing scientific knowledge in a manner that is intuitively digestible, and piercing. I especially focus on the offensiveness of art, both in the way: 1) an art piece at first glance can shock us and put us in a place of discomfort at what we are witnessing, which can move us out of the routine comfort we might feel with the injustices going on around us, and 2) the way art can be offensive (like the offence of a sports team) in the pursuit towards establishing a more just world. Art need not be relegated to illustrating the beautiful, instead by illustrating the horrific, it can inspire towards the realization of the beautiful in our world.
The UC Davis Art/Science Fusion Program was co-founded by entomologist/artist Diane Ullman and artist Donna Billick. Ullman is a professor and former chair of the UC Davis Department of Entomology (now Entomology and Nematology) and a former associate dean for undergraduate academic programs, College of Agricultural and Environmental Sciences. Billick is a self-described "rock artist" who has degrees in art and science (genetics). She retired from UC Davis earlier this year as a course instructor with the UC Davis Art/Science Fusion Program but continues her art.
Related Links: Rick Karban
Kin Recognition
New Yorker