In a study published online this week in Proceedings of the National Academy of Sciences, NC State’s Dr. Ed Vargo and colleagues from Japan and Switzerland show that a combination of two chemical compounds in a pheromone perfume emitted by egg-laying females known as secondary queens can inhibit other termites from developing into new queens. Moreover, the study shows that termite eggs also produce the caste-altering chemicals.
“This study opens up a whole new world into the mechanisms behind the ways colonies of termites and other social insects regulate themselves,” Vargo says. “With this long missing key ingredient now in hand, I expect we’ll see rapid progress in understanding how reproductive and nonreproductive termite castes develop.”
Secondary queens don’t prevent other termites in the colony from becoming mommies out of spite, Vargo says. It’s more a case of keeping the colony balanced with the correct numbers of caste members. Colonies need the proper proportion of workers who forage for food and take care of larvae, soldiers who defend the colony, and secondary queens who lay eggs to increase a colony’s numbers. The wrong balance could spell doom for the colony.
Termites molt frequently throughout their lives and can change castes depending on conditions in the colony. In the study, the scientists exposed different castes of termites that have the capacity to become secondary queens to both the actual pheromone perfume elicited from secondary queens and a synthetic version of the perfume. Both treatments prevented termites from becoming secondary queens.
Scientists have long believed that queen pheromones regulate caste development in social insects, but this finding is only the second such discovery in the past 50 years – when the term pheromone was coined by scientists. This is partly due, Vargo says, to scientists looking for the wrong types of chemicals.
“The pheromone – a combination of two chemicals called n-butyl-n-butyrate and 2-methyl-1-butanol – is a low-weight, volatile blend that acts directly on developing termites,” he says. That is in contrast to queen honey bees, for example, whose pheromone acts indirectly by regulating the queen-rearing behavior of worker bees.
NC State’s Department of Entomology is part of the university’s College of Agriculture and Life Sciences.
- kulikowski -
“Identification of a pheromone regulating caste differentiation in termites”
Authors: Kenji Matasuura, Chihiro Himuro, Tomoyuki Yokoi and Yuuka Yamamoto, Okayama University; Edward L. Vargo, North Carolina State University; Laurent Keller, University of Lausanne
Published: The week of July 5, 2010, in Proceedings of the National Academy of Sciences
Abstract: The hallmark of social insects is their caste system: reproduction is primarily monopolized by queens, whereas workers specialize in the other tasks required for colony growth and survival. Pheromones produced by reining queens have long been believed to be the prime factor inhibiting the differentiation of new reproductive individuals. However, there has been very little progress in the chemical identification of such inhibitory pheromones. Here we report the identification of a volatile inhibitory pheromone produced by female neotenics (secondary queens) that acts directly on target individuals to suppress the differentiation of new female neotenics and identify n-butyl-n-butyrate and 2-methyl-1-butanol as the active components of the inhibitory pheromone. An artificial pheromone blend consisting of these two compounds had a strong inhibitory effect similar to live neotenics. Surprisingly, the same two volatiles are also emitted by eggs, playing a role both as an attractant to workers and an inhibitor of reproductive differentiation. This dual production of an inhibitory pheromone by female reproductives and eggs probably reflects the recruitment of an attractant pheromone as an inhibitory pheromone and may provide a mechanism ensuring honest signaling of reproductive status with a tight coupling between fertility and inhibitory power. Identification of a volatile pheromone regulating caste differentiation in a termite provides insights into the functioning of social insect colonies and opens important avenues for elucidating the developmental pathways leading to reproductive and nonreproductive castes.
Dr. Ed Vargo | EurekAlert!
Smart Data Transformation – Surfing the Big Wave
02.12.2016 | Fraunhofer-Institut für Angewandte Informationstechnik FIT
Climate change could outpace EPA Lake Champlain protections
18.11.2016 | University of Vermont
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
07.12.2016 | Health and Medicine
07.12.2016 | Life Sciences
07.12.2016 | Health and Medicine