Study Shows Bee Brains Process Positive and Negative Experiences Differently

Phys.org By Bob Yirka September 11, 2019

Credit: CC0 Public Domain

Credit: CC0 Public Domain

A team of researchers at the University of Illinois at Urbana-Champaign has found that when bees experience positive versus negative events, their brains process and remember the events differently. In their paper published in Proceedings of the Royal Society B, the group describes their study of bee brain processing and memory retention and what they found.

Scientists have known for a long time that vertebrates handle positive and negative events differently, storing and retrieving those memories in their brains differently, as well. In this effort, the researchers wanted to know if the same could be said of invertebrates such as the common honeybee. To find out, they exposed test bees to positive or negative events and then studied gene expression in a part of their brain known as the mushroom body—an area involved in processing sensory information, learning and memory.

More specifically, the researchers exposed the bees to positive experiences such as tending to their young or negative experiences such as dealing with a threat like an enemy or a predator. They then quickly froze the bees to keep the brain chemical state intact. Next, they studied the brain chemistry related to gene expression in samples taken from the mushroom bodies, focusing on genes that prior research has shown respond very quickly to external stimuli. The team then looked for differences in other parts of the mushroom bodies after the bee had been exposed to a positive or negative event. They report that they did find differences between the two, which, they suggest, indicates that bee brains process and store memories of the two types of events differently. The researchers were surprised by the results, considering the very small size of the bee brain.

The researchers suggest their findings could lead to a better understanding of social behavior in invertebrates and how they respond to different sorts of stimuli. They also note that because of the two types of memory involved in the two types of events, there is a link between vertebrate and invertebrate cognition despite the two groups diverging approximately 600 million years ago.

More information: Ian M. Traniello et al. Valence of social information is encoded in different subpopulations of mushroom body Kenyon cells in the honeybee brain, Proceedings of the Royal Society B: Biological Sciences (2019). DOI: 10.1098/rspb.2019.0901

Journal information: Proceedings of the Royal Society B

https://phys.org/news/2019-09-bee-brains-positive-negative-differently.html

Related: https://medicalxpress.com/news/2018-09-brain-function-impacts-contribute-depression.html

New Laboratory System Allows Researchers To Probe The Secret Lives Of Queen Bees

Phys.org University of Illinois at Urbana-Champaign December 3, 2018

Researchers at the Carl R. Woese Institute for Genomic Biology at the University of Illinois used specially developed 3D-printed plastic honey combs that mimic the hive environment, in order to monitor queen egg-laying behaviors. Credit: Bee Research Facility, University of Illinois

Researchers at the Carl R. Woese Institute for Genomic Biology at the University of Illinois used specially developed 3D-printed plastic honey combs that mimic the hive environment, in order to monitor queen egg-laying behaviors. Credit: Bee Research Facility, University of Illinois

More than a decade after the identification of colony collapse disorder, a phenomenon marked by widespread loss of honey bee colonies, scientists are still working to untangle the ecologically complex problem of how to mitigate ongoing losses of honey bees and other pollinating species. One much-needed aid in this effort is more efficient ways to track specific impacts on bee health. To address this need, a group of Illinois researchers has established a laboratory-based method for tracking the fertility of honey bee queens.

Co-first authors Julia Fine and Hagai Shpigler, both postdoctoral researchers at the University of Illinois, worked with others in the laboratory of Carl R. Woese Institute for Genomic Biology Director and Swanlund Professor of Entomology Gene Robinson to establish a laboratory set-up that would mimic the key aspects of the hive environment and allow detection of egg-laying by honey bee queens living with small groups of worker bees. The resulting system, described in PLOS ONE, allowed them to explore the relationship between worker nutrition and queen fertility.

"The idea that honey bee nutrition influences colony level metrics of reproduction has been demonstrated before, but here, we examined an old story using new tools," Fine said. "We were able to get a clearer picture of how nutrition can affect the relationship between honey bee workers and queens and how this can impact the queen's egg production."

Populations of many pollinator species have been declining in the US and worldwide. Studies of factors influencing wild and managed honey bee hives have identified four main factors influencing health: parasites, pathogens, pesticides, and poor nutrition. These factors can influence one another. For example, parasites may spread pathogens, much as fleas do on people, while poor nutrition might increase the likelihood of foraging on contaminated food sources.

Egg production is a vital aspect of honey bee colony function. Queens lay eggs that hatch into the thousands of worker bees that keep the colony running, as well as males and young queens to allow the colony to propagate. But in the dark, bustling interior of a standard hive, it is challenging to monitor egg laying or to evaluate the impacts of environmental factors.

"Egg laying occurs in the darkness of a hive occupied by thousands of workers and is therefore hard to track," Shpigler said. "Queen egg laying was never studied outside of the colony; the biggest challenge was to give the queens the right conditions for continuous egg laying outside of natural conditions."

To move queen productivity successfully into the lab, the researchers focused on the essentials of their natural environment. They developed a 3-D-printed plastic honey comb that they refined to mimic what a queen would experience in the hive, which ensured that the cage environment could be carefully controlled and kept pesticide free. They also provided each queen with a small group of worker bees to feed and support the queen; this element became the inspiration for their first experiments with the new system.

"Honey bee queens only ingest food in the form of glandular secretions provided to them by their worker caretakers, and queens are not known to lay eggs without the support of their worker bees," Fine said. "The more we worked in this system, the more it became apparent that the easiest way to influence the queen was to first influence the worker bees that care for her. Once we identified this strategy, designing effective experiments became easier."

Fine, Shpigler, and their coauthors provided each group of caged bees with honey, water, and sucrose solution, but varied the source of fat and protein: some bees were fed with a paste of honey and either a low or a high amount of floral pollen, while others were fed with bee bread, a mixture of pollen, honey, and secretions produced by worker honey bees that preserve and ferment the pollen. The researchers monitored how queen egg laying behavior was influenced by the type of diet fed to the workers caring for her.

They found that when a group of workers was fed pollen paste, the queen they attended was likely to increase her egg laying more slowly in the laboratory environment than a queen attended by bee bread-fed workers. This difference was most noticeable when the lower-percentage pollen paste was used, but persisted even in bees fed the richer pollen paste.

The results affirmed the importance of nutrition to queen productivity, as well as demonstrating the potential utility of the laboratory set-up for investigating other factors affecting queen behavior and health.

"The effect of the nutrition . . . was our first successful use of the system, giving us hope for more success in the future," Shpigler said. "The results show very nicely how the honey bee colony functions as one body, with shared digestive and reproductive systems. The workers are the ones that eat the food and the effect is on the queen egg laying—the superorganism in action!"

"It's been exciting to see the kind of quantitative data that we can generate with this system using fewer resources relative to studies that use full size honey bee colonies," Fine said. "Eventually, we hope that this system can be adapted as a risk assessment tool to identify other factors that positively and negatively influence honey bee reproduction . . . there is an immediate need for a laboratory system that can be used to quantitatively assess risks to honey bee queen health and reproduction."

More information: Julia D. Fine et al, Quantifying the effects of pollen nutrition on honey bee queen egg laying with a new laboratory system, PLOS ONE (2018). DOI: 10.1371/journal.pone.0203444

Journal reference: PLoS ONE

Provided by: University of Illinois at Urbana-Champaign 

https://phys.org/news/2018-12-laboratory-probe-secret-queen-bees.html#jCp

Study Finds Parallels Between Unresponsive Honey Bees, Human Autism

University of Illinois at Urbana-Champaign     July 31, 2017

Socially unresponsive bees share something fundamental with autistic humans, new research finds. Credit: Graphic by Julie McMahonCHAMPAIGN, Ill. — Honey bees that consistently fail to respond to obvious social cues share something fundamental with autistic humans, researchers report in a new study. Genes most closely associated with autism spectrum disorders in humans are regulated differently in unresponsive honey bees than in their more responsive nest mates, the study found.

The findings, reported in the Proceedings of the National Academy of Sciences, appear to be unique to genes associated with autism and not to other behavioral disorders in humans.

The study is a first glimpse of the molecular heritage shared across the animal kingdom, the researchers say, and offers tantalizing clues about the evolution of social behavior.

“Some honey bees are more active than others, and some appear indifferent to intruders that threaten the hive. This, in itself, is not unusual,” said University of Illinois entomology professor Gene Robinson, who led the new analysis. “Honey bees take on different roles at different stages of their lifecycle, and not every bee can – or should – function as a guard.”

But when postdoctoral researcher Hagai Shpigler observed that some of those same bees also were unmoved by the presence of queen larvae – a stimulus that typically spurs diligent action in nurse bees – it suggested something unusual was going on, said Robinson, who directs the Carl R. Woese Institute for Genomic Biology at the U. of I.

“For any given task, most honey bees fall somewhere in the highly engaged to moderately engaged camp,” Robinson said. “Typically, honey bees will respond more robustly to one stimulus than to another.”

But a small subset of bees tested by Robinson and his colleagues were either always on – energetically responding both to intruders and to queen larvae – or always off, he said.

The unresponsive bees’ lack of social awareness might be seen as similar to the social difficulties faced by some people with autism, Robinson said. But comparing behavior is not enough, he said. Analyzing the genes that drive behavior and how those genes are regulated is key to understanding whether the two phenomena are related.

To get at this question, the team analyzed 246 groups of bees from seven genetically distinct honey bee colonies, carefully testing each bee in various social contexts, then analyzing levels of gene expression in their brains. They found that more than 1,000 genes were regulated differently between unresponsive bees, nurse bees and guards.

The researchers next turned to a list of genes and gene expression profiles associated with autism in humans. Their goal was to determine whether a significant proportion of the autism-related genes also played a role in the unresponsive bees.

“We figured out a way to make an unbiased statistical test that will tell us whether a human gene list and a honey bee gene list overlap more or less than expected by chance,” said Michael Saul, a postdoctoral researcher who led the statistical analysis with statistics professor Sihai D. Zhao.

That test revealed significant overlap between the unresponsive honey bees’ gene expression profile and genes closely associated with autism in humans. Further analyses found no significant overlap with human genes associated with depression, schizophrenia or several other mental disorders, or with other bee gene lists.

“Our data are telling us that social unresponsiveness does have some common molecular characteristics in these distantly related species,” Robinson said.

“It’s important to point out some caveats,” he said. “Humans are not big bees and bees are not little humans. The social responsiveness depends on context, and is different in the two cases. Autism spectrum disorder is very complex, and unresponsiveness is not the only behavior associated with it.”

While social behavior likely evolved independently in honey bees and humans, Robinson said, “our data reveal that they make use of common toolkits, common building blocks.”

“What really excites me about this study is that there appears to be this kernel of similarity between us and honey bees, a common animal inheritance that potentially drives social behavior in similar ways,” Saul said. “We haven’t proved this, but this work is telling us where to look for that in the future.”

More information: Hagai Y. Shpigler el al., "Deep evolutionary conservation of autism-related genes," PNAS (2017). www.pnas.org/cgi/doi/10.1073/pnas.1708127114 

Read more at: https://phys.org/news/2017-07-parallels-unresponsive-honey-bees-human.html#jCp

When Worker Bees Get a Promotion

The New York Times/Science     By James Gorman   September 8, 2014

The honeybee hive would not seem to be the place to look for individuality, flexibility in job duties and social mobility. But by using new techniques for analyzing bee behavior, researchers at the University of Illinois at Urbana-Champaign, recently found that the life of a bee is less rigidly determined than had been thought.

They first discovered that an elite 20 percent of foragers do 50 percent of all the foraging, and then found that membership in this group was surprisingly flexible. When the elite bees were removed from the hive, less hard-working bees raised the level of their activity and a new elite emerged.

Gene E. Robinson, the director of the Institute for Genomic Biology at the university, said he and other researchers set out to look at the behavior of bees in a new way partly because of “an increasing appreciation of the role of the individual in social insects.”

Teasing out the differences in individual levels of foraging activity required some new tools, both for observing the bees and for analyzing the data.

To work on the first part of the problem, Dr. Robinson said, Paul Tenczar, a retired computer entrepreneur and enthusiastic citizen scientist, joined the lab. He worked with scientists to devise a kind of E-ZPass system for bees involving tiny electronic ID tags, entry and exit tubes for a hive, and laser scanners to track the bees as they passed through the tubes (think toll plazas).

But even with the technology functioning at a high level to track the bees’ activity, analytical tools had to be developed to understand and interpret the data, Dr. Robinson said.

The results, which the team of scientists reported in the September issue of Animal Behaviour, showed first that there was an elite group among the foraging bees.

Then, by removing those top performers, the team found that other bees took their place. It was, said Dr. Robinson, “elitism with a populist streak.”

They also found, in mining the data, that over the life of an individual bee, patterns of foraging activity fluctuated and that individual bees had different life histories.

The approach to studying behavior using so-called big data is like that used by Internet companies to track people’s shopping behavior. Such new techniques, Dr. Robinson said, showed the power of “massive amounts of surveillance” to “reveal previously inaccessible data about individual behavior” in insects. And just when bees thought Facebook had ignored them.

Read at... 

 

Radio Frequency ID Tags on Honey bees Reveal Hive Dynamics

 This message brought to us by CATCH THE BUZZ: Kim Flottum    July 22, 2014

CHAMPAIGN, Ill. — Scientists attached radio-frequency identification (RFID) tags to hundreds of individual honey bees and tracked them for several weeks. The effort yielded two discoveries: Some foraging bees are much busier than others; and if those busy bees disappear, others will take their place.

The findings are reported in the journal Animal Behaviour.

Tagging the bees revealed that about 20 percent of the foraging bees in a hive brought home more than half of the nectar and pollen gathered to feed the hive.

"We found that some bees are working very, very hard – as we would have expected," said University of Illinois Institute for Genomic Biology director Gene E. Robinson, who led the research. "But then we found some other bees that were not working as hard as the others."

Citizen scientist Paul Tenczar developed the technique for attaching RFID tags to bees and tracking their flight activity with monitors. He and Neuroscience Program graduate student Claudia Lutz measured the foraging activities of bees in several locations, including some in hives in a controlled foraging environment. (Watch a video about this work.)

Vikyath Rao, a graduate student in the laboratory of U. of I. physics professor Nigel Goldenfeld, analyzed the data using a computer model Rao and Goldenfeld developed.

Previous studies, primarily in ants, have found that some social insects work much harder than others in the same colony, Robinson said.

"The assumption has always been that these 'elite' individuals are in some way intrinsically better, that they were born that way," he said.

While it is well known that genetic differences underlie differences in many types of behavior, the new findings show that "sometimes it is important to give individuals a chance in a different situation to truly find out how different they are from each other," Robinson said.

Removal of the elite bees "was associated with an almost five-fold increase in activity level in previously low-activity foragers," the researchers wrote. The change occurred within 24 hours, Tenczar said. This demonstrates that other individuals within the hive also have the capacity to become elites when necessary, Robinson said.

"It is still possible that there truly are elite bees that have some differential abilities to work harder than others, but it's a larger group than first estimated," Robinson said. "Or it could be that all bees are capable of working at this level and there's some kind of colony-level regulation that has some of them working really, really hard, making many trips while others make fewer trips."

Perhaps the less-busy bees function as a kind of reserve force that can kick into high gear if something happens to the super-foragers, Robinson said.

"Our observation is that the colony bounces back to a situation where some bees are very active and some are less active," he said. "Why is that? We don't know. Do all bees have that capability? We still don't know."

Read at: http://home.ezezine.com/1636/1636-2014.07.23.07.08.archive.html

Read more at: http://www.sciencedirect.com/science/article/pii/S0003347214002589

CATCH THE BUZZ: Kim Flottum,  Bee Culture, The Magazine Of American Beekeeping, published by the A.I. Root Company. Twitter.FacebookBee Culture’s Blog.