Improved Regulation Needed As Pesticides Found to Affect Genes in Bees

EurekAlert From: Queen Mary University of London March 6, 2019

Bumblebee Colony Credit: TJ Colgan

Bumblebee Colony Credit: TJ Colgan

Scientists are urging for improved regulation on pesticides after finding that they affect genes in bumblebees, according to research led by Queen Mary University of London in collaboration with Imperial College London.

For the first time, researchers applied a biomedically inspired approach to examine changes in the 12,000 genes that make up bumblebee workers and queens after pesticide exposure.

The study, published in Molecular Ecology, shows that genes which may be involved in a broad range of biological processes are affected.

They also found that queens and workers respond differently to pesticide exposure and that one pesticide they tested had much stronger effects than the other did.

Other recent studies, including previous work by the authors, have revealed that exposure even to low doses of these neurotoxic pesticides is detrimental to colony function and survival as it impairs bee behaviours including the ability to obtain pollen and nectar from flowers and the ability to locate their nests.

This new approach provides high-resolution information about what is happening at a molecular level inside the bodies of the bumblebees.

Some of these changes in gene activity may represent the mechanisms that link intoxification to impaired behaviour.

Lead author of the study Dr Yannick Wurm, from Queen Mary University of London, said: "Governments had approved what they thought were 'safe' levels but pesticides intoxicate many pollinators, reducing their dexterity and cognition and ultimately survival. This is a major risk because pollinators are declining worldwide yet are essential for maintaining the stability of the ecosystem and for pollinating crops.

"While newer pesticide evaluation aims to consider the impact on behaviour, our work demonstrates a highly sensitive approach that can dramatically improve how we evaluate the effects of pesticides."

The researchers exposed colonies of bumblebees to either clothianidin or imidacloprid at field-realistic concentrations while controlling for factors including colony social environment and worker age.

They found clothianidin had much stronger effects than imidacloprid - both of which are in the category of 'neonicotinoid' pesticides and both of which are still used worldwide although they were banned in 2018 for outdoor use by the European Union.

For worker bumblebees, the activity levels of 55 genes were changed by exposure to clothianidin with 31 genes showing higher activity levels while the rest showed lower activity levels after exposure.

This could indicate that their bodies are reorienting resources to try to detoxify, which the researchers suspect is what some of the genes are doing. For other genes, the changes could represent the intermediate effects of intoxification that lead to affected behaviour.

The trend differed in queen bumblebees as 17 genes had changed activity levels, with 16 of the 17 having higher activity levels after exposure to the clothianidin pesticide.

Dr Joe Colgan, first author of the study and also from Queen Mary University of London, said: "This shows that worker and queen bumblebees are differently wired and that the pesticides do not affect them in the same way. As workers and queens perform different but complementary activities essential for colony function, improving our understanding of how both types of colony member are affected by pesticides is vital for assessing the risks these chemicals pose."

The researchers believe that the approach they have demonstrated must now be applied more broadly. This will provide detailed information on how pesticides differ in the effects they have on beneficial species, and why species may differ in their susceptibility.

Dr Colgan said: "We examined the effects of two pesticides on one species of bumblebee. But hundreds of pesticides are authorised, and their effects are likely to substantially differ across the 200,000 pollinating insect species which also include other bees, wasps, flies, moths, and butterflies."

Dr Wurm added: "Our work demonstrates that the type of high-resolution molecular approach that has changed the way human diseases are researched and diagnosed, can also be applied to beneficial pollinators. This approach provides an unprecedented view of how bees are being affected by pesticides and works at large scale. It can fundamentally improve how we evaluate the toxicity of chemicals we put into nature."

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Research paper: 'Caste- and pesticide-specific effects of neonicotinoid pesticide exposure on gene expression in bumblebees'. Thomas J. Colgan, Isabel K. Fletcher, Andres N. Arce, Richard J. Gill, Ana Ramos Rodrigues, Eckart Stolle, Lars Chittka and Yannick Wurm. Molecular Ecology.

https://www.eurekalert.org/pub_releases/2019-03/qmuo-irn030519.php

Earning a Bee's Wings

Washington State University-St. Louis (The Source) By Talia Ogliore February 20, 2019

In hives, graduating to forager a requirement for social membership

It is a classic coming-of-age story, in many ways.

A honey bee hatches and grows up deep inside a hive. Surrounded by 40,000 of her closest relatives, this dark and constantly buzzing place is all that she knows. Only after she turns 21 days old does she leave the nest to look for pollen and nectar. For her, this is a moment of great risk, and great reward.

It’s also the moment at which she becomes recognizable to other bees, according to new research from Washington University in St. Louis. A study in the journal eLife reports that honey bees (Apis mellifera) develop different scent profiles as they age, and the gatekeeper bees at the hive’s door respond differently to returning foragers than they do when they encounter younger bees who have never ventured out before.

This work offers new insight into one of the most important interactions in the lives of social insects: recognizing self and other

Ben-Shahar

Ben-Shahar

Until this point, most bee researchers thought bees recognize and respond to a scent that is the homogenized scent of all of the members of their own colony. That’s how it works for some ants and other insects, at least. But new work from the laboratory of  Yehuda Ben-Shahar, associate professor of biology in Arts & Sciences, shows that nestmate recognition instead depends on an innate developmental process that is associated with age-dependent division of labor. The work was completed in collaboration with researchers from the lab of Joel Levine at the University of Toronto.

“It was always assumed that the way that honey bees acquire nestmate recognition cues, their cuticular hydrocarbon (CHC) profiles, is through these mechanisms where they rub up against each other, or transfer compounds between each other,” said Cassondra L. Vernier, a graduate student at Washington University and first author of the new study.

“You would expect, then, that even younger bees would have a very similar pheromonal profile as older bees. When in fact that is not what we saw,” she said.

Vernier compared the CHC profiles of bees on the day they were born and at 1 week, 2 weeks, and 3 weeks old. The 3-week-old bees had significantly different profiles than their younger siblings.

Graduate student Cassondra Vernier conducted lab experiments and observed hours of bee interactions at the entrance to the hive. She is shown here at Tyson Research Center, Washington University’s environmental field station. (Courtesy photo)

Graduate student Cassondra Vernier conducted lab experiments and observed hours of bee interactions at the entrance to the hive. She is shown here at Tyson Research Center, Washington University’s environmental field station. (Courtesy photo)

Vernier compared the CHC profiles of bees on the day they were born and at 1 week, 2 weeks, and 3 weeks old. The 3-week-old bees had significantly different profiles than their younger siblings.A 3-week-old foraging bee also has a very different job to support the hive than a younger bee — one who spends her time as a nurse caring for bee larvae and building the waxy honeycomb structures in the hive.

The researchers wanted to separate out whether the differences they saw were based on age alone, or were somehow tied to the older bees’ foraging activities. Bees that exit the hive to collect nectar encounter lots of scents on flowers and other surfaces they touch. They also are exposed to different environmental factors such as sunshine and rain that could affect their body coatings.

So Vernier also compared the CHC profiles of foraging-age bees that were held in the hive and not permitted to forage with bees that were able to venture out. These two groups were also significantly different.

“What we found is that it’s actually a combination of both — of being at the age for foraging, and actually performing the foraging activities,” said Ben-Shahar.

Guards are gatekeepers; specific triggers still unknown

Importantly, not every bee notices the difference in scent profiles. Guard bees are the only ones who care to identify outsiders.

“They sit in the entrance and they have a very specific posture,” Ben-Shahar said of the guards. “They’re very attentive. Their forelegs are usually raised, and they’re very alert. Still, it is hard to know who they are until they react to somebody.”

Place a 1-day-old, 1-week-old, or 2-week-old outsider on the stoop in front of a guard, and she is likely to be able to waltz on through. But it’s a different story after 3 weeks of age — when guards bite, sting and/or drag outsiders away from the door.

“Nestmate recognition is something that is very context-specific. It involves an interaction between very specific bees within the colony,” Ben-Shahar said. “Most bees are completely oblivious. Most colony members don’t produce the signal that tells anyone if they belong or not, and they don’t care about the signal. They don’t react to it.”

As an important caveat, the new study does not directly address the mechanism by which cue specificity is determined in bees. Which specific components of the honey bee CHC profile represent the nestmate recognition cue remains unknown.

“Something environmentally related is causing expression-level changes in the CHC profiles of the bees,” Vernier said. “That’s our model for now.”

The bees in this study were kept in two different locations: Tyson Research Center, the environmental field station for Washington University in St. Louis, and an amateur beekeeper’s private residence in University City, MO.

Funding for the project was provided by the National Science Foundation under grants NSF DGE-1143954, IOS-1322783, IOS-1707221 and IOS-1754264.

https://source.wustl.edu/2019/02/earning-a-bees-wings/

Biologists Identify Honeybee 'Clean' Genes Known For Improving Survival

PHYS.org York University February 15, 2019

Credit: CC0 Public Domain

Credit: CC0 Public Domain

The key to breeding disease-resistant honeybees could lie in a group of genes—known for controlling hygienic behaviour—that enable colonies to limit the spread of harmful mites and bacteria, according to genomics research conducted at York University.

Some worker honeybees detect and remove sick and dead larvae and pupae from their colonies. This hygienic behaviour, which has a strong genetic component, is known to improve the colony's chance of survival. The researchers narrowed in on the "clean" genes that influence this behaviour to understand the evolution of this unique trait.

The finding, published today in the journal Genome Biology and Evolution, could lead to a new technique for use in selective breeding programs around the world to enhance the health of honeybees.

"Social immunity is a really important trait that beekeepers try to select in order to breed healthier colonies," said Professor Amro Zayed, a bee genomics expert in the Department of Biology, Faculty of Science. "Instead of spending a lot of time in the field measuring the hygienic behaviour of colonies, we can now try breeding bees with these genetic mutations that predict hygienic behaviour."

Statistics Canada estimates that honeybee pollination contributes between $3.15 to $4.39 billion per year to the Canadian economy including some of Canada's most lucrative crops like apples, blueberries and canola. In Canada, and around the world, beekeepers have experienced higher than normal colony losses. Last winter, Canadian beekeepers lost up to 33 per cent of their colonies.

"This study opens the door to using genomics to breed healthier and disease-resistant colonies that have higher social immunity," explained Zayed. "This is of huge importance to the greater community of geneticists who are interested in understanding the genetics of this novel trait."

Zayed worked on the study with 13 bee biologists from York University, University of British Columbia, University of Manitoba, and Agriculture and Agri-Food Canada.

In the study, the biologists sequenced the genomes of three honeybee populations; two of them bred to express highly hygienic behaviour and a third population with typical hygiene. Brock Harpur, Zayed's former doctoral student who is now an assistant professor at Purdue University's Department of Entomology, examined the genomes of bees from each of these three populations and looked for areas that differ between the unhygienic and hygienic bees. Harpur pinpointed at least 73 genes that likely control this hygienic trait.

"Now that we have identified these candidate genes, we can look for the mechanisms of hygienic behavior and begin to develop tools for beekeepers to breed healthier colonies," explained Harpur.

The biologists are planning to pilot a marker-assisted breeding program for hygienic behaviour, in which bees are selected for breeding based solely on their genetic information.

"We think there is a lot of potential here of breeding disease-resistant colonies with a simple genetic test," said Zayed.

Explore further: New genetic test will improve biosecurity of honey bees around the globe

More information: Brock A Harpur et al, Integrative Genomics Reveals the Genetics and Evolution of the Honey Bee's Social Immune System, Genome Biology and Evolution (2019). DOI: 10.1093/gbe/evz018

Provided by: York University

https://phys.org/news/2019-02-biologists-honeybee-genes-survival.html#jCp

Bees Have Brains for Basic Maths: Study

RMIT University By Gosia Kaszubska February 7, 2019

Researchers have found bees can do basic mathematics, in a discovery that expands our understanding of the relationship between brain size and brain power.

Building on their finding that honeybees can understand the concept of zero, Australian and French researchers set out to test whether bees could perform arithmetic operations like addition and subtraction.

Solving maths problems requires a sophisticated level of cognition, involving the complex mental management of numbers, long-term rules and short term working memory.

The revelation that even the miniature brain of a honeybee can grasp basic mathematical operations has implications for the future development of Artificial Intelligence, particularly in improving rapid learning.

Led by researchers from RMIT University in Melbourne, Australia, the new study showed bees can be taught to recognise colours as symbolic representations for addition and subtraction, and that they can use this information to solve arithmetic problems.

RMIT’s Associate Professor Adrian Dyer said numerical operations like addition and subtraction are complex because they require two levels of processing.

“You need to be able to hold the rules around adding and subtracting in your long-term memory, while mentally manipulating a set of given numbers in your short-term memory,” Dyer said.

“On top of this, our bees also used their short-term memories to solve arithmetic problems, as they learned to recognise plus or minus as abstract concepts rather than being given visual aids.

“Our findings suggest that advanced numerical cognition may be found much more widely in nature among non-human animals than previously suspected.

“If maths doesn’t require a massive brain, there might also be new ways for us to incorporate interactions of both long-term rules and working memory into designs to improve rapid AI learning of new problems.”

There is considerable debate around whether animals know or can learn complex number skills.

Many species can understand the difference between quantities and use this to forage, make decisions and solve problems. But numerical cognition, such as exact number and arithmetic operations, requires a more sophisticated level of processing.

Previous studies have shown some primates, birds, babies and even spiders can add and/or subtract. The new research, published today in Science Advances, adds bees to that list. 

A school for bees? How the honeybees were trained

The experiment, conducted by PhD researcher Scarlett Howard in the Bio Inspired Digital Sensing-Lab (BIDS-Lab) at RMIT, involved training individual honeybees to visit a Y-shaped maze.

The bees received a reward of sugar water when they made a correct choice in the maze, and received a bitter-tasting quinine solution if the choice was incorrect.

Honeybees will go back to a place if the location provides a good source of food, so the bees returned repeatedly to the experimental set-up to collect nutrition and continue learning.

When a bee flew into the entrance of the maze they would see a set of elements, between 1 to 5 shapes. The shapes were either blue, which meant the bee had to add, or yellow, which meant the bee had to subtract.

After viewing the initial number, the bee would fly through a hole into a decision chamber where it could choose to fly to the left or right side of the maze.

One side had an incorrect solution to the problem and the other side had the correct solution of either plus or minus one. The correct answer was changed randomly throughout the experiment to avoid bees learning to visit just one side of the maze.

At the beginning of the experiment, bees made random choices until they could work out how to solve the problem. Eventually, over 100 learning trials that took 4 to 7 hours, bees learned that blue meant +1, while yellow meant -1. The bees could then apply the rules to new numbers.

Scarlett Howard said the ability to do basic maths has been vital in the flourishing of human societies historically, with evidence that the Egyptians and Babylonians used arithmetic around 2000BC.

“These days, we learn as children that a plus symbol means you need to add two or more quantities, while a minus symbol means you subtract,” she said.

“Our findings show that the complex understanding of maths symbols as a language is something that many brains can probably achieve, and helps explain how many human cultures independently developed numeracy skills.”

The research, with collaborators from University of Toulouse and the ARC Centre of Excellence for Nanoscale Biophotonics at RMIT, is published today ("Numerical cognition in honeybees enables addition and subtraction", Science Advances, DOI 10.1126/sciadv.aav0961).

Video: Kiralee Greenhalgh

https://www.rmit.edu.au/news/all-news/2019/feb/bees-brains-maths

Our 'Bee-Eye Camera' Helps Us Support Bees, Grow Food And Protect The Environment

To help draw bees’ attention, flowers that are pollinated by bees have typically evolved to send very strong colour signals. Credit:  Shutterstock

To help draw bees’ attention, flowers that are pollinated by bees have typically evolved to send very strong colour signals. Credit: Shutterstock

Walking through our gardens in Australia, we may not realise that buzzing around us is one of our greatest natural resources. Bees are responsible for pollinating about a third of food for human consumption, and data on crop production suggests that bees contribute more than US$235 billion to the global economy each year.

By pollinating native and non-native plants, including many ornamental species, honeybees and Australian native bees also play an essential role in creating healthy communities – from urban parks to backyard gardens.

Despite their importance to human and environmental health, it is amazing how little we know how about our hard working insect friends actually see the world.

By learning how bees see and make decisions, it's possible to improve our understanding of how best to work with bees to manage our essential resources.

How bee vision differs from human vision

A new documentary on ABC TV, The Great Australian Bee Challenge, is teaching everyday Australians all about bees. In it, we conducted an experiment to demonstrate how bees use their amazing eyes to find complex shapes in flowers, or even human faces.

Humans use the lens in our eye to focus light onto our retina, resulting in a sharp image. By contrast, insects like bees use a compound eye that is made up of many light-guiding tubes called ommatidia.

Insects in the city: a honeybee forages in the heart of Sydney. Credit: Adrian Dyer/RMIT University

Insects in the city: a honeybee forages in the heart of Sydney. Credit: Adrian Dyer/RMIT University

The top of each ommatidia is called a facet. In each of a bees' two compound eyes, there are about 5000 different ommatidia, each funnelling part of the scene towards specialised sensors to enable visual perception by the bee brain.

Since each ommatidia carries limited information about a scene due to the physics of light, the resulting composite image is relatively "grainy" compared to human vision. The problem of reduced visual sharpness poses a challenge for bees trying to find flowers at a distance.

To help draw bees' attention, flowers that are pollinated by bees have typically evolved to send very strong colour signals. We may find them beautiful, but flowers haven't evolved for our eyes. In fact, the strongest signals appeal to a bee's ability to perceive mixtures of ultraviolet, blue and green light.

Building a bee eye camera

Despite all of our research, it can still be hard to imagine how a bee sees.

How we see fine detail with our eyes, and how a bee eye camera views the same information at a distance of about 15cm. Credit: Sue Williams and Adrian Dyer/RMIT University

How we see fine detail with our eyes, and how a bee eye camera views the same information at a distance of about 15cm. Credit: Sue Williams and Adrian Dyer/RMIT University

So to help people (including ourselves) visualise what the world looks like to a bee, we built a special, bio-inspired "bee-eye" camera that mimics the optical principles of the bee compound eye by using about 5000 drinking straws. Each straw views just one part of a scene, but the array of straws allows all parts of the scene to be projected onto a piece of tracing paper.

The resulting image can then be captured using a digital camera. This project can be constructed by school age children, and easily be assembled multiple times to enable insights into how bees see our world.

Because bees can be trained to learn visual targets, we know that our device does a good job of mimicking a bees visual acuity.

Student projects can explore the interesting nexus between science, photography and art to show how bees see different things, like carrots – which are an important part of our diet and which require bees for the efficient production of seeds.

Yellow flower (Gelsemium sempervirens) as it appears to our eye, as taken through a UV sensitive camera, and how it likely appears to a bee. Credit: Sue Williams and Adrian Dyer/RMIT University

Yellow flower (Gelsemium sempervirens) as it appears to our eye, as taken through a UV sensitive camera, and how it likely appears to a bee. Credit: Sue Williams and Adrian Dyer/RMIT University

Understanding bee vision helps us protect bees

Bees need flowers to live, and we need bees to pollinate our crops. Understanding bee vision can help us better support our buzzy friends and the critical pollination services they provide.

In nature, it appears that flowers often bloom in communities, using combined cues like colour and scent to help important pollinators find the area with the best resources.

Having lots of flowers blooming together attracts pollinators in much the same way that boxing day sales attract consumers to a shopping centre. Shops are better together, even though they are in competition – the same may be true for flowers!

This suggests that there is unlikely to be one flower that is "best" for bees. The solution for better supporting bees is to incorporate as many flowers as possible – both native and non native – in the environment. Basically: if you plant it, they will come.

We are only starting to understand how bees see and perceive our shared world – including art styles – and the more we know, the better we can protect and encourage our essential insect partners.

How a bee eye camera works by only passing the constructive rays of light to form an image. Credit: Sue Williams and Adrian Dyer/RMIT University

How a bee eye camera works by only passing the constructive rays of light to form an image. Credit: Sue Williams and Adrian Dyer/RMIT University

Clip from “The Great Australian Bee Challenge, Episode 2.

Looking at the fruits and vegetables of bee pollination; a bee camera eye view of carrots. Credit: Sue Williams and Adrian Dyer/RMIT University

Looking at the fruits and vegetables of bee pollination; a bee camera eye view of carrots. Credit: Sue Williams and Adrian Dyer/RMIT University

Finding An Elusive Mutation That Turns Altruism Into Selfish Behavior Among Honeybees

Phys.org    From Oxford University Press     January 8, 2019

A. m. capensis pseudoqueens  (black bees) among  A. m. scutellata  host workers (yellow bees). Credit: Picture taken by Mike Allsopp

A. m. capensis pseudoqueens (black bees) among A. m. scutellata host workers (yellow bees). Credit: Picture taken by Mike Allsopp

Among the social insects, bees have developed a strong and rich social network, where busy worker bees tend to the queen, who in turn, controls reproduction for the benefit of the hive.

But the South African Cape honey bee (Apis mellifera capensis) can flout these rules. In a process of genetic trickery called thelytoky syndrome, worker bee females ignore the queen's orders and begin to reproduce on their own.

Scientists, in their own altruistic effort to protect the Cape honey bees from a recent devastating blight, transferred the Cape honey bees to a northeastern region—-only to see the Cape bees wreak havoc among colonies of the neighboring honey bee subspecies A. m. scutellata.

The A. capensis bees turned from altruistic workers to the guests who would not leave—-becoming social parasites that forage on their own into foreign colonies, reproducing an army of loyal workers, stealing all the honey, and eventually, dethroning the queen and taking over the host colony.

This type of behavior, despite making for bad neighbors, makes a lot of evolutionary sense. If the queen is lost, then the thelytoky syndrome at one point must have first kicked in as a life raft to save the colony. But if this is the case, why hasn't it become a more widespread phenomenon for other bee species?

Recently, scientists have combed through bee genomes to narrow down the genetics behind thelytoky, and linked these to candidate genes in the past few years—-but to date, the master genetic switch has not been found.

Now, for the first time, a group led by Denise Aumer and Eckart Stolle, working in the lab of Robin Moritz at the Martin-Luther-Universität Halle-Wittenberg's Institute of Biology, have finally found the root cause responsible for thelytoky. The findings were published in the advanced online edition of Molecular Biology and Evolution.

"Uncovering the genetic architecture underlying thelytoky is a big step towards understanding this mode of reproduction, not only in the Cape honeybee, but also in other insect species in general (e.g. many invasive ants reproduce in a very similar fashion)," said Stolle. "After having worked on the topic for so many years with so much efforts by our colleagues and us to add pieces to the puzzle and also with the one or other dead end, it is a huge accomplishment for us to have come to this point."

By comparing the genomes of Cape honeybees which produce diploid female offspring (thelytoky) with those producing haploid male offspring (arrhenotoky, i.e. the expected mode of reproduction), they identified a candidate gene located on chromosome one, LOC409096, and proposed to call it Thelytoky (Th), as the major regulator of the selfish worker bee reproduction. Thelytoky encodes a receptor protein with a transmembrane helix and a signal peptide at the extracellular N-terminus, indicating that it is linked to a secretory pathway.

A. m. capensis pseudoqueen  (bee with white tag on thorax) eliciting retinue behavior in the surrounding  A. m. scutellata  host bees. Credit: Picture taken by Mike Allsopp.

A. m. capensis pseudoqueen (bee with white tag on thorax) eliciting retinue behavior in the surrounding A. m. scutellata host bees. Credit: Picture taken by Mike Allsopp.

Specifically, a single mutational substitution in exon 7 of Thelytoky causes a change from the polar amino acid threonine to the non-polar amino acid isoleucine in the protein sequence, leading to substantial structural modifications and likely functional consequences. In addition, they confirmed their genetic data by showing that RNA levels of Thelytoky were elevated only in the selfish bees. They also performed DNA sequencing of another honey bee population and found the same exact mutation amongst the socially parasitic lineage of the Cape honey bee, but not among workers of other honey bee subspecies.

From the study of the genetics, they determined that Cape bee selfishness exhibits a dominant inheritance pattern, which means that only one mutation that needs to be passed down to perform the selfish genetic switch.

But the genetics are a bit more complicated because it turns out that the selfish gene still needs its altruistic partner (known as the social, or arrhenotoky form of the gene).

"The genetic control of the thelytoky syndrome is regulated by a more complex genetic mechanism than previously assumed," said Aumer. "The thelytoky allele (Th) is not recessive, i.e., needing two copies of the mutated gene, but rather a dominant allele. This dominant mutation expresses the phenotype (thelytoky) when one copy of the gene is the mutated variant, and the other copy is the one variant typical for the Cape honey bee."

"But at the same time, it appears that having two copies of the mutated variant is detrimental, perhaps even lethal, while having two copies of the "regular" Cape bee variant of this genes makes them reproduce normally. Any other combination of the mutated variant with another subspecies' variant would be non-matching alleles and would result in either non-functional or fertile normally reproducing (arrhenotokous) phenotypes. Therefore, the Cape bee typical Th variant seems to complement the mutated Th variant in a way that the offspring is fertile and expresses the unique set of phenotypes referred to as thelytoky syndrome."

Because only one gene can get passed on during reproduction, the genetics not only explain why breeders, for the past 150 years, have been mostly unsuccessful with producing thelytokous workers from mating the Cape bees with others, but also why the thelytoky behavior hasn't spread into other bee populations.

Genetically, it turns out you still need a little altruism to be truly selfish. When only one is passed on from interbreeding, the effect is lost without its partner gene.

"On a broader level, the identified genetic architecture of thelytoky in honey bees may serve as a model for other eusocial species with similar thelytokous reproduction, in particular for novel ant model systems, such as Platythyrea punctata and the clonal raider ant Ooceraea biroi," wrote the authors in the Molecular Biology and Evolution publication.

And just like the striking case of malaria and hemoglobin genes in humans, the study shows how just a single change in the DNA can have such a dramatic effect on a species, or in this case, changing the behavior of a bee from a helper to a mercenary.

Read more at: https://phys.org/news/2019-01-elusive-mutation-altruism-selfish-behavior.html#jCp
Journal reference: Molecular Biology and Evolution  
Provided by: Oxford University Press

Here’s How Clumps Of Honeybees May Survive Blowing In The Wind

Science News    By Emily Conover     September 17, 2018

In lab tests, the insects adjust their positions to flatten out the cluster and keep it stable.

BEE BALL Certain types of bees tend to arrange into clusters on tree branches. Bees move around within a clump to maintain its stability, a new study finds.

A stiff breeze is no match for a clump of honeybees, and now scientists are beginning to understand why.

When scouting out a new home, the bees tend to cluster together on tree branches or other surfaces, forming large, hanging clumps which help keep the insects safe from the elements. To keep the clump together, individual honeybees change their positions, fine-tuning the cluster’s shape based on external forces, a new study finds. That could help bees deal with such disturbances as wind shaking the branches.

A team of scientists built a movable platform with a caged queen in the center, around which honeybees clustered in a hanging bunch. When the researchers shook the platform back and forth, bees moved upward, flattening out the clump and lessening its swaying, the team reports September 17 in Nature Physics.

The insects, the scientists hypothesized, might be moving based on the strain — how much each bee is pulled apart from its neighbors as the cluster swings. So the researchers made a computer simulation of a bee cluster to determine how the bees decided where to move.

When the simulated bees were programmed to move to areas of higher strain, the simulation reproduced the observed flattening of the cluster, the researchers found. As a bee moves to a higher-strain region, the insect must bear more of the burden. So by taking one for the team, the bees ensure the clump stays intact.

O. Peleg et al. Collective mechanical adaptation of honeybee swarms. Nature Physics. Published online September 17, 2018. doi:10.1038/s41567-018-0262-1.

https://www.sciencenews.org/article/heres-how-clumps-honeybees-may-survive-blowing-wind

Epigenetic Patterns Determine If Honeybee Larvae Become Queens Or Workers

Science Daily / Queen Mary University of London    August 22, 2018

Scientists at Queen Mary University of London and Australian National University have unravelled how changes in nutrition in the early development of honeybees can result in vastly different adult characteristics.

Queen and worker honeybees are almost genetically identical but are fed a different diet as larvae. The researchers have found that specific protein patterns on their genome play an important role in determining which one they develop into.

These proteins, known as histones, act as switches that control how the larvae develop and the diet determines which switches are activated. They found that the queen develops faster and the worker developmental pathway is actively switched on from a default queen developmental programme.

This change is caused by epigenetics -- a dynamic set of instructions that exist 'on top' of the genetic information, that encode and direct the programme of events that leads to differential gene expression and worker or queen developmental outcome.

The study, published in Genome Research, describes the first genome wide map of histone patterns in the honeybee and the first between any organism of the same sex that differs in reproductive division of labour.

Bees are also very important pollinators -- so it is crucial to understand their molecular biology, how they develop and the mechanisms that regulate this.

Lead author Dr Paul Hurd, from Queen Mary University of London, said: "The ability of an individual larva to become a worker or a queen is due to the way genes are switched on or off in response to the specific diet; this determines such differing outcomes from the same genome."

"We show that queens and workers have specific histone patterns even though their DNAs are the same. These proteins control both structural and functional aspects of the organism's genetic material and have the capacity to determine which part of the genome, and when, has to be activated to respond to both internal and external stimuli."

The histones have small chemical tags, or epigenetic modifications, that allow them to act differently to those that do not, usually by allowing access to the DNA and genes. This enables identical DNA to behave in different ways because it is wrapped around histones with different chemical (epigenetic) tags.

Co-author Professor Ryszard Maleszka, from Australian National University, added: "The extent of histone modifications uncovered by this study was remarkable and exceeded our expectations. We were able to identify where the important differences are in the genomes of workers and queen."

Epigenetic information can be altered by environmental factors, including diet. In the case of the honeybee, the queen larvae are fed a diet of royal jelly, a potent substance capable of changing developmental instructions.

Dr Hurd said: "Think of the genome as the instruction book of everything that is possible but the epigenetics is the way in which those instructions are read. Epigenetics is about interpretation and of course there are many different ways to interpret these instructions and when and in response to what."

The authors found that some of the most important epigenetic differences are in regions of the honeybee genome that are not part of genes. For the first time, these caste-specific regulatory DNA regions that are so important in making a queen or a worker have been identified.

Professor Maleszka said: "Our findings are important because a high level of similarity of epigenetic tool kits between honeybees and mammals makes this familiar insect an invaluable system to investigate the sophistications of epigenetic regulation that cannot be addressed in humans or other mammals."


Story Source:

Materials provided by Queen Mary University of London. Note: Content may be edited for style and length.


Journal Reference:

Marek Wojciechowski, Robert Lowe, Joanna Maleszka, Danyal Conn, Ryszard Maleszka, Paul J. Hurd. Phenotypically distinct female castes in honey bees are defined by alternative chromatin states during larval development. Genome Research, 2018; DOI: 10.1101/gr.236497.118

https://www.sciencedaily.com/releases/2018/08/180822130958.htm

Honeybee Hive-Mates Influenced To Fan Wings To Keep Hive Cool

Phys.org  University of Colorado at Boulder  By Kenna Bruner    August 3, 2018

Credit: University of Colorado at Boulder

Rachael Kaspar used to be scared of bees. That was before she studied their behavior as an undergraduate at CU Boulder. Since learning their secret lives and social behaviors, she has developed an appreciation for the complex, hard-working bees.

Honeybees fan their wings to cool down their hives when temperatures rise, but a new study shows that an individual honeybee's fanning behavior influences individual and group fanning behavior in hive-mates.

Kaspar graduated in 2016 with a bachelor's degree in ecology and evolutionary biology, and in environmental studies with a minor in atmospheric and oceanic sciences. While a sophomore, she joined the lab of ecology and evolutionary biology professor Michael Breed to work with then-doctoral student Chelsea Cook and became interested in organized behavior and responses to environmental stress.

She is the lead author of a scientific article in Animal Behaviour based on her undergraduate honors thesis about honeybee behavior, which shows experienced fanner honey bees influence younger, inexperienced bees to fan their colony to cool it down. Her study tested the hypothesis that an individual bee can influence group members to perform thermoregulatory fanning behavior in the western honey bee, Apis mellifera L.

Building upon this behavior is Kaspar's finding that shows young nurse bees are influenced by seeing older, more experienced worker bees fanning their wings—also known as fanners. The younger nurse bees then join in to help regulate the hive's temperature. The fanners influenced the nurses' thermal response threshold and probability to fan, but most notably, fanners had the greatest influence when they were the initiators—the first to fan in the group.

"The older workers are definitely influencing the younger nurse bees," Kaspar said. "I was interested in how different age groups socially interacted, what are the variances between age groups and how are they interacting to have a proper homeostatic response to environmental stressors."

In the paper, she states that the survival of an animal society depends on how individual interactions influence group coordination. Interactions within a group determine coordinated responses to environmental changes. This behavior is exemplified by honeybee worker responses to increasing ambient temperatures by fanning their wings to circulate air through the hive. Their previous research demonstrated that groups of workers are more likely to fan than isolated workers, which suggests a coordinated group response.

Hive temperatures that exceed 96.8 degrees Fahrenheit put larvae at risk of death or developing abnormalities. This is just one reason why it is crucial that individual bees have a coordinated group fanning response to properly regulate the temperature of the hive.

Credit: University of Colorado at BoulderHoneybees divide their tasks among female age groups. Nurses, who are between zero and 10 days old, take care of the larvae and the brood. Middle-aged worker bees, who are 10 to 20 days old, can be found on the front porch, as well as on the inside of the hive guarding and cleaning the hive, and fanning to cool the hive. The more outwardly visible bees are the foragers, which are 20–30 days old and fly from flower to flower collecting nectar and pollen.

Researchers marked bees with water-soluble paint to identify them in the hive. When researchers warmed groups of bees, they would observe the bees' fanning behavior and record the temperature at which individuals and groups began to fan.

"When I was down there with my face right in front of the hive, I could feel the air moving from their wings fanning," she said.

This social and influential behavior, Kaspar says, can be seen in a variety of organisms throughout the biological index, from elephants to chimpanzees to fish. And perhaps not surprisingly, in humans as well.

"You would think that bees as insects wouldn't have the capability to learn, remember or have these social influences. But, in fact, they do. Bees are a great model to use for studying other societies, like us."

Kaspar got the idea of an influencer or an initiator of hive behavior when she observed human behavior unfolding at a cross walk on campus. A group of people were waiting for the light to change so they could cross. Too impatient to wait, one person strode across the street. A second or two later, the rest of the pedestrians crossed too, influenced by the behavior of the first person to cross against the light.

"When I saw that I was shocked," she said. "This is exactly what I was studying in honeybees and there I was seeing it in people on campus."

Kaspar is a professional research assistant in the Department of Anesthesiology at the CU Anschutz Medical Campus. She is working in Eric Clambey's laboratory, where they are identifying unique cell phenotypes and interactions in human lungs and the gastrointestinal tract to better understand the effect of micro-environments on viruses and inflammation. Her goal is to start graduate school in 2020 and continue her studies into how organisms come together to improve their chances of survival.

"I love bees, though," she said. "I would very much like to continue studying honeybees in some way."

Explore further: Honeybees more likely to regulate hive's 'thermostat' during rapid temperature increases

More information: Rachael E. Kaspar et al. Experienced individuals influence the thermoregulatory fanning behaviour in honey bee colonies, Animal Behaviour (2018). DOI: 10.1016/j.anbehav.2018.06.004

Read more at: https://phys.org/news/2018-08-honeybee-hive-mates-fan-wings-hive.html#jCp

Drift

      By Dan Wyns     June 12, 2018

     Drift




Bees have incredible navigation abilities that allow them to fly miles away from the colony to forage and return home with enough precision to locate the entrance to their colony, even when there are dozens of nearly identical hives within a small apiary site. The current understanding of navigation is that a combination of position relative to the sun and landmarks across the landscape get them close and then a combination of visual cues and pheromones to precisely locate the colony entrance. When a returning forager ends up returning to the wrong colony, she is typically not attacked as a robbing bee but accepted into the colony due to the pollen or nectar she carries. This process, known as drift, can lead to significant variations in colony strength over time and increase the potential for the spread of diseases and parasites within an apiary. Drift is generally not viewed as a huge problem, but there are some steps beekeepers can take to mitigate the amount of drift happening in their apiaries.

When colonies are aggregated in large numbers and placed in rows of pallets, as is common in a commercial setting, there is potential for excessive drift. Many beekeepers elect to paint all of their woodware white, and this decision may be based on tradition, aesthetic, or other considerations. Others use a variety of colors, which creates a more vibrant apiary and may also help returning forages with orientation. While bees do not see the same spectrum of colors as humans, they are able to distinguish between different shades, assisting them in orientation. In general dark colors should be avoided, particularly in excessively warm and sunny locations, so colonies will not become excessively hot. However, a mix of pastel colors and tones can provide some variation to help bees distinguish individual colonies without adding the potential for thermal stress.

In addition to variations in color, placement relative to other colonies and objects in the landscape can offer navigational aids that limit drift. Many beekeepers have observed that when a number of colonies are placed in a long line the colonies at the downwind end of the line accumulate more bees and yield greater honey harvests while those at the upwind end of the line are often short on bees and lighter in honey stores. By placing an array of hives in circles or arcs, with entrances pointed in different directions, the downwind drift effect can be lessened.  Prominent landscape features can also be helpful in providing orientation assistance. In addition to potentially providing a windbreak, a structure, tree line, or hedgerow close to hives can reduce drift. Orientation landmarks can be particularly important when setting up yards for mating nucs. It is essential that queens return to the correct nuc after orientation and mating flights so extra consideration should be given to visual cues in order to minimize drift in mating yards.

Drift is not something that most beekeepers give a lot of thought and it is certainly not among the most critical factors impacting colony health. Nevertheless, there is a growing understanding of the impacts of horizontal transmission of varroa mites between colonies and the ability to control varroa levels within and between apiaries. Phoretic varroa on drifting foragers are one way that ‘clean’ colonies may become reinfested. Given the ever-increasing number of challenges to bee management, reducing drift represents one area where beekeepers can potentially reduce colony stress for a minimal amount of effort.

https://beeinformed.org/2018/06/11/drift/

 

 

Bee Research May Redefine Understanding Of Intelligence

The Japan Times     By Rowan Hooper    November 28, 2017

Honeybees have the ability to tell other bees in the hive where flowers bearing nectar and pollen are located. | ISTOCKThe brain of a honeybee is tiny — the size of a pin head — and contains less than a million neurons, compared to the 85 billion in our own brains. Yet with that sliver of brain, bees can do some extraordinary things. They can count and interpret abstract patterns. Most famously, bees have the ability to communicate the location of flowers to other bees in the hive.

When a foraging bee has found a source of nectar and pollen, it can let others in the hive know by performing a peculiar figure-of-eight dance called the waggle dance. The information contained in the waggle dance was first decoded by Austrian biologist Karl von Frisch, who picked up a Nobel Prize for his discovery in 1973. The dance in itself is not as complex as true language, but it’s remarkable in that it’s a symbolic form of communication.

Recently, Hiroyuki Ai at Fukuoka University has made another breakthrough in our understanding of this extraordinary behavior, by investigating the neurons that allow bees to process the dance information. Bees get information from hearing the dance, as well as seeing it. During the dance, bees vibrate their abdomens as they run in a figure-of-eight pattern. These vibrations send out pulses that are picked up by an organ on the antennae called Johnston’s organ. Johnston’s organs are equivalent to our ears.

Ai maintains hives of honeybees on the campus of Fukuoka University. (Incidentally, he says they have monthly meetings to discuss their research with students, after which they have tea parties and eat the honey produced by their bees.) Until recently, there has been very little understanding of how the bee brain deciphers the information encoded in the waggle dance. The reason, he says, is that bees only perform the dance in the hive, and it’s difficult to get them to do it in the laboratory.

It makes sense that the bees pay attention to sound. “In a dark hive, they can’t see the dance,” Ai says. “Honeybees hear the dance.” Honeybees are very sensitive to vibration, so mimicking the noise of a waggle dance can cause bees to journey to the same place indicated by a real dance.

Ai and his team recorded the vibrations made by the waggle dance, simulated the noises and applied the vibrations to the antennae of bees in the lab. This allowed them to track which neurons fired in response to the waggle dance, and follow their route in the insect brain.

The team discovered three different types of “interneurons.” These are connecting neurons that allow communication between different parts of the brain. Ai, along with team members that include Thomas Wachtler at Ludwig-Maximilians University in Munich, Germany, and Hidetoshi Ikeno of the University of Hyogo in Himeji, traced the path of interneurons in the part of the brain concerned with processing sound. They found that the way the interneurons turn on and off is key to encoding information contained in the waggle dance about distance.

This mechanism of turning on and off — in neuroscience it is called “disinhibition” — is similar to one used in other insects. For example, it’s how crickets listen to the songs of other crickets as well as how moths assess the distance from the source of a smell their antennae have picked up. Ai and his team suggest there is a common neural basis in the way these different species do things.

Communication is the key to forming complex societies. It’s what allows the honeybee to perform such extraordinary behaviors. And, naturally, language is a key factor in human success. Intelligence is required for both these things, so does this mean honeybees, with a minuscule brain, are intelligent? It’s a tricky quality to define. One attempt, from the American Psychological Association Task Force on Intelligence, defines it as the ability “to adapt efficiently to the environment and to learn from experience.” Bees are able to do this.

There are six different kinds of dance, for example, and bees are able to learn and change their behavior accordingly. If bees encounter a dead bee at a flower, they change the pattern of dancing they perform back at the hive, suggesting they can perform a risk/benefit analysis.

Both bee and human language are a consequence of intelligence, and research such as Ai’s forces us to rethink what we mean by intelligence. “There might be a common brain mechanism between humans and honeybees,” he says.

What it certainly shows is that you don’t need a big brain to be smart. As with many things, Charles Darwin realized this, writing in 1871: “The brain of an ant is one of the most marvellous atoms of matter in the world, perhaps more so than the brain of man.”

https://www.japantimes.co.jp/news/2017/11/28/national/science-health/bee-research-may-redefine-understanding-intelligence/#.WiydclWnHIU

Honey Bees Fill ‘Saddlebags’ With Pollen. Here’s How They Keep Them Gripped Tight

ScienceMagazine.org     By Katherine Kornei     November 27, 2017

Heidi and Hans-Juergen Koch/Minden PicturesBees don’t just transport pollen between plants, they also bring balls of it back to the hive for food. These “pollen pellets,” which also include nectar and can account for 30% of a bee’s weight, hang off their hind legs like overstuffed saddlebags (pictured). Now, researchers have investigated just how securely bees carry their precious cargo. The team caught roughly 20 of the insects returning to their hives and examined their legs and pollen pellets using both high-resolution imaging and a technique similar to an x-ray. Long hairs on the bees’ legs helped hold the pollen pellets in place as the animals flew, the team reported last week at the 70th Annual Meeting of the American Physical Society Division of Fluid Dynamics in Denver. The researchers then tugged on some of the pollen pellets using elastic string. They found that the pellets, though seemingly precarious, were firmly attached: The force necessary to dislodge a pellet was about 20 times more than the force a bee typically experiences while flying. These findings can help scientists design artificial pollinators in the future, the team suggests.

http://www.sciencemag.org/news/2017/11/honey-bees-fill-saddlebags-pollen-here-s-how-they-keep-them-gripped-tight

Mаn Investigаtes If Honeybees Reаlly Hаve To Die When They Sting

Animal Planet Life

Do honey bees reаlly hаve to die when they sting? This video from Аrvin Pierce аbout bees sets out to find out.

The beekeeper explаins thаt if bees sting other insects, they’ll likely survive, but if they sting аn аnimаl with “elаstic skin” (like people), yes, they аre likely to die аs their innаrds аre pulled out when they try to retrieve their stingers.

 

But there аre exceptions, аs Pierce shows in the video.

Pierce lets the bees sting him аnd, insteаd of swаtting them, he gives them time to get loose. Within 25-30 seconds severаl of the bees mаnаge to retrieve their stinger аnd fly off – surviving the experience!

He explаins thаt stinging is the lаst thing honey bees wаnt to do. They do it аs defense, not аggression. So if you wаnt to sаve а bee’s life “don’t slаp thаt bee, just give them time to get free,” sаys Pierce.

The beekeeper аdmits, thаt no one will probаbly wаnt to wаit the seconds needed for the bees to retrieve their stingers, but it’s а “nice to know”.

Pierce’s key tаke-аwаy is to help people understаnd thаt bees don’t leаve their hive looking for somebody to s t i n g. Their mаin goаl is to seek out food sources аnd bring them bаck to their hive.

But this is аn increаsing chаllenge for honey bees. So Pierce wаnts people to help them by providing а “secure, cleаn environment with heаlthy food sources”.

Thаt sounds like а good ideа for everyone, don’t you think?

http://www.reshareworthy.com/honeybees-sting/

(Cautionary note: Make sure if you're working with your bees in areas with Africanized Honey Bees to wear protective clothing.)

Honey Bees Inspire Crime-Fighting Algorithm

UPI / Science News     By Brooks Hayes    April 17, 2017

The research could help police target the bad actors most important to a crime network's functionality and efficiency.

By studying the social network within a bee colony, scientists hope to bolster the crime-fighting abilities of law enforcement officials. Photo by University of GranadaScientists at the University of Granada, in Spain, have created a new algorithm to help law enforcement dismantle problematic social networks, including criminal and terror networks. The researchers inspiration: honey bees.

The bio-inspired algorithm can be used to analyze the connections and relationships among a social network and identify the most dangerous nodes or individuals. Analysis provided by the algorithm could help law enforcement dismantle crime networks or terror cells more effectively and efficiently.

Bee colonies feature highly efficient social structures. They are composed of an organized workforce with well-defined tasks, and their organization and efficiency is reliant upon effective communication.

"Bees form fairly well organized societies, in which each member has a specific role," Manuel Lozano Márquez, a computer scientist at Granada, said in a news release. "There are three main types: scout bees, which are looking for food sources; worker bees, who collect food; and supervisor bees, who wait in the colony."

Scientists at Granada decided to study bee colony organization and behavior -- and the flow of information among different types of bees -- as a model for understanding harmful social networks.

Their analysis showed the traditional method for combating pernicious social networks can be improved upon. Traditionally, law enforcement officials attack crime networks by targeting the most active or dangerous individuals. But removing most important players doesn't ensure the cell or network falls apart.

"In order to find the most effective way of dismantling a network, it is necessary to develop and put into action an optimization process that analyzes a multitude of situations and selects the best option in the shortest time possible," said Humberto Trujillo Mendoza, a behavioral scientist at Granada. "It's similar to what a chess program does when identifying, predicting and checking the possible steps or paths that may occur in a game of chess from a given moment and movement."

The latest research -- detailed in the Journal Information Sciences -- can help officials identify not just the most active or dangerous links within a harmful network, but the nodes or actors most important to the network's functionality and efficiency.

http://www.upi.com/Science_News/2017/04/17/Honey-bees-inspire-crime-fighting-algorithm/6591492434124/

The Threat of Robbing

Perfect Bee Facebook Page    April 11, 2017

The following is from the Perfect Bee Facebook Page: "At this time of year beekeepers install new hives and overwintered colonies start exploring again, after the winter cluster has worked its magic. In the next few weeks there will be a focused effort by our bees to build up their numbers.

But for the smaller or weaker colony there is another challenge. A good example is the installation of a package of bees. A common and effective way for new beekeepers to establish their first hives, a package results in around 10,000 starting out in a new home.

But 10,000 still represents a small colony. While the numbers expand, there's always the chance of robbing. A colony may not have the capability to successfully defend the hive.

Our article "The Threat of Robbing" looks at why and how robbing occurs and what steps you, as a beekeeper, can take to help your bees protect their space."

Read text and view videos at Perfet Bee's Blog post by Mark Williams: "The Threat of Robbing."

Honey Bees Have Keen Eyesight

Morning AgClips    By Dr. Elisa Rigosi, Lund University/University of Adelaide    April 9, 2017

A western honey bee, also known as a European honey bee (Apis mellifera). Researchers at Lund University, Sweden, and the University of Adelaide, Australia, have shown that honey bees have much sharper eyesight than previously known. (Dr Elisa Rigosi, Lund University) - See more at: https://www.morningagclips.com/honey-bees-have-keen-eyesight. (Dr. Elisa Rigosi, Lund University)WASHINGTON — Research conducted at the University of Adelaide has discovered that bees have much better vision than was previously known, offering new insights into the lives of honey bees, and new opportunities for translating this knowledge into fields such as robot vision.

The findings come from “eye tests” given to western honey bees (also known as European honey bees, Apis mellifera) by postdoctoral researcher Dr Elisa Rigosi (Department of Biology, Lund University, Sweden) in the Adelaide Medical School, under the supervision of Dr Steven Wiederman (Adelaide Medical School, University of Adelaide) and Professor David O’Carroll (Department of Biology, Lund University, Sweden).

The results of their work are published today in the Nature journal Scientific Reports.

Bee vision has been studied ever since the pioneering research of Dr Karl von Frisch in 1914, which reported bees’ ability to see colours through a clever set of training experiments.

“Today, honey bees are still a fascinating model among scientists, in particular neuroscientists,” Dr Rigosi says.

“Among other things, honey bees help to answer questions such as: how can a tiny brain of less than a million neurons achieve complex processes, and what are its utmost limits? In the last few decades it has been shown that bees can see and categorise objects and learn concepts through vision, such as the concept of ‘symmetric’ and ‘above and below’.

“But one basic question that has only been partially addressed is: what actually is the visual acuity of the honey bee eye? Just how good is a bee’s eyesight?”

Dr Wiederman says: “Previous researchers have measured the visual acuity of bees, but most of these experiments have been conducted in the dark. Bright daylight and dark laboratories are two completely different environments, resulting in anatomical and physiological changes in the resolution of the eye.

“Photoreceptors in the visual system detect variations in light intensity. There are eight photoreceptors beyond each hexagonal facet of a bee’s compound eye, and their eyes are made out of thousands of facets! Naturally, we expected some differences in the quality of bees’ eyesight from being tested in brightly lit conditions compared with dim light,” he says.

Dr Rigosi, Dr Wiederman and Professor O’Carroll set out to answer two specific questions: first, what is the smallest well-defined object that a bee can see? (ie, its object resolution); and second, how far away can a bee see an object, even if it can’t see that object clearly? (ie, maximum detectability limit).

To do so, the researchers took electrophysiological recordings of the neural responses occurring in single photoreceptors in a bee’s eyes. The photoreceptors are detectors of light in the retina, and each time an object passes into the field of vision, it registers a neural response.

Dr Rigosi says: “We found that in the frontal part of the eye, where the resolution is maximised, honey bees can clearly see objects that are as small as 1.9° – that’s approximately the width of your thumb when you stretch your arm out in front of you.

“This is 30% better eyesight than has been previously recorded,” she says.

“In terms of the smallest object a bee can detect, but not clearly, this works out to be about 0.6° – that’s one third of your thumb width at arm’s length. This is about one third of what bees can clearly see and five times smaller than what has so far been detected in behavioural experiments.

“These new results suggest that bees have the chance to see a potential predator, and thus escape, far earlier than what we thought previously, or perceive landmarks in the environment better than we expected, which is useful for navigation and thus for survival,” Dr Rigosi says.

Dr Wiederman says this research offers new and useful information about insect vision more broadly as well as for honey bees.

“We’ve shown that the honey bee has higher visual acuity than previously reported. They can resolve finer details than we originally thought, which has important implications in interpreting their responses to a range of cognitive experiments scientists have been conducting with bees for years.

“Importantly, these findings could also be useful in our work on designing bio-inspired robotics and robot vision, and for basic research on bee biology,” he says.

This research has been supported with funding from the Australian Research Council (ARC), the Swedish Research Council, and the Swedish Foundation for International Cooperation in Research and Higher Education.

https://www.morningagclips.com/honey-bees-have-keen-eyesight/

University of Adelaide

Bees Learn While They Sleep, And That Means They Might Dream

 A new study suggests that bees can store information in long-term memory 
while they sleep, just like humans do when we dream

For all our obvious differences, humans and honeybees share some common threads within the fabric of life.

We are both social species. While humans speak and write to communicate, honeybees dance to one another; waggling their bodies for specific durations at angles that indicate where the best pockets of nectar or pollen are to be found outside the hustle and bustle of the nest.

But only forager bees – the eldest of several types of honeybee castes – do this. Just like in human populations, the honeybee colony is divided into different sectors of work. There are cleaners, nurses, security guards, not to mention collection bees whose sole job is to cache nectar in comb. 

Different honeybees do different jobs in the colony (Credit:Pete Oxford/naturepl.com) 

Different honeybees do different jobs in the colony (Credit:Pete Oxford/naturepl.com)

 

As they age, honeybees are promoted through a diverse career, from waste disposal to the more familiar forager.

But it is not all work, work, work. Busy bees have to sleep, too.

Similar to our circadian rhythm, honeybees sleep between five and eight hours a day. And, in the case of forager bees, this occurs in day-night cycles, with more rest at night when darkness prevents their excursions for pollen and nectar.

But, given that a hive's primary purpose is productivity and yield, why should a large portion of the population seemingly waste up to a third of the day resting? What are the benefits of sleep?

Over the last few years, a handful of scientists have started to uncover why honeybees need to rest; their findings adding to the list of threads that we share. 

What goes on inside that head? (Credit: Kim Taylor/naturepl.com) 

What goes on inside that head? (Credit: Kim Taylor/naturepl.com) 

Ever since Aristotle studied the monarchy of the honeybee colony in the 3rd Century BC, the species Apis mellifera has been studied by generations of dedicated scientists, each able to discover something entirely new.

"The bee's life is like a magic well: the more you draw from it, the more it fills with water," wrote Karl von Frisch, the German Nobel laureate who decoded their waggle dances, in 1950.

It was in 1983 that a researcher called Walter Kaiser made a new discovery: that honeybees slept. As he watched through his observation hive, Kaiser noted how a bee's legs would first start to flex, bringing its head to the floor. Its antennae would stop moving. In some cases, a bee would fall over sideways, as if intoxicated by tiredness. Many bees held each other's legs as they slept.

Kaiser's study was the first record of sleep in an invertebrate. But it was far from the last. The scuttle of cockroaches, the flutter of fruit flies, and the rhythmic undulations of jellyfishes all have temporary periods of quiescence. 

Even jellyfish seem to sleep (Credit: Aflo/naturepl.com) 

Even jellyfish seem to sleep (Credit: Aflo/naturepl.com)  

"The evidence appears to align with this idea that sleep is shared across all animals," says Barrett Klein, a sleep biologist from the University of Wisconsin Wisconsin–La Crosse. "There's no universally-accepted exception."

Being so prevalent, sleep seems to be a very important part of complex life. To understand why honeybees sleep, a long line of scientists has been keeping forager bees up at night. How do they function sans sleep? Not well, it seems.

For one, they cannot communicate properly. Instead of performing their waggle dances with incredible accuracy, sleepy bees become sloppy. Their interpretive dances fail to translate the direction of a profitable food source.

And since their nest mates use this information as a guide for their foraging trips, they are likely to be sent slightly astray, wasting time and energy on the wing. The whole colony suffers. 

It's not all work, work, work (Credit: MD Kern Palo Alto JR Museum/naturepl.com) 

It's not all work, work, work (Credit: MD Kern Palo Alto JR Museum/naturepl.com) 

Further, sleep-deprived honeybees find it difficult to return to the hive when visiting fresh flower patches, spending more time reorienting themselves with the sky and surrounding landmarks as their compass. Many even get lost and never return, so their rest becomes much more permanent.

Without a good night's sleep, then, honeybees start to forget the activities that should be second nature to them. And in a study released in 2015, Randolf Menzel and his colleagues from the Free University of Berlin provided a possible explanation as to why this might be.

As is well-documented in humans, deep sleep (known as slow-wave sleep) consolidates memories, transferring them from short-term to long-term memory. Menzel and his team wanted to know whether the same was true for the humble honeybee.

First, they had to teach them something new; only then could they test the quality of their short-term to long-term memory transfer. They chose a tried-and-tested protocol, developed by Menzel himself in 1983.

When feeding, honeybees exhibit a stereotyped behaviour: sticking out their long tubular mouthparts, or proboscis, to slurp up dinner. But, by presenting honeybees with a specific odour and burst of heat as they feed, this proboscis extension response (PER) can be elicited even when there is no food available.

 

Bees have busy lives (Credit: Kim Taylor/naturepl.com) 

Bees have busy lives (Credit: Kim Taylor/naturepl.com) 

It is the honeybee equivalent of the famous Pavlov's dog response. Rather than a bell, the bees associate the odour-heat combo with food and try to feed.

Only it is much easier to condition bees than dogs. Honeybees are quick learners, associating the odour and heat with food after one to three trials. After that, PER happened without the need for a reward.

"If you work with them, you realise very quickly that they are very smart," says Hanna Zwaka, one of the study's authors. "They are also very sweet to watch while they are learning."

Once conditioned, the bees were allowed a full night's sleep within their own personalised plastic tube. As they slept in solitude, the team exposed some of the honeybees to the conditioned odour-heat combo during different sleep stages, ranging from light sleep to deep sleep, allowing any activity in their brains to be further stimulated.

As a control, a separate group of bees were exposed to a neutral odour – paraffin oil – that would not reactivate any conditioned responses.

When the honeybees woke the next day, the memory tests could begin. Did the bees with the night-time reminders hold on to their conditioned response – sticking out their proboscis – for longer than those without? 

When honeybees wake, do they remember? (Credit: Phil Savoie/naturepl.com) 

When honeybees wake, do they remember? (Credit: Phil Savoie/naturepl.com) 

Yes, but only when the odour and heat were presented in the deep-sleep stage, just like we would expect for a sleep-reinforced memory in humans. Presenting the odour and heat during other, lighter stages of sleep offered no advantage in memory retention.

Although their bodies might be inactive during deep-sleep, honeybee brains do not seem to be. The previous day's activities are reactivated, stabilising fragile memories and converting them into a more permanent form that can be accessed the next day – or perhaps even further in the future.

In sleeping rats, memory consolidation has been shown to work like replaying a tape: any learned responses, such as completing a complex maze, are repeated over and over again in the same sequence that they occurred; right turn by wrong turn, neuron by neuron in the brain. 

Sleeping rats are still learning (Credit BonkersAboutScience/Alamy) (Credit: Credit BonkersAboutScience/Alamy) 

Sleeping rats are still learning (Credit BonkersAboutScience/Alamy) 

Menzel and colleagues' study adds some tantalising evidence that the same might be occurring in bees.

"It's a beautifully conducted study with regard to memory," says Klein. But he has some caveats: "Whether or not the results relate to deep sleep is up for discussion." No study has yet clearly demonstrated stages or depth of sleep in insects, he says; only promising hints and suggestions.

Both labs hope to replicate these results with more streamlined, and telling, methods.

With the possibility of memory reactivation in the bees' sleepy heads, Menzel's work begs the question of whether honeybees dream.  

Do bees dream of these? (Credit: Sunny_mjx/CC by 2.0) 

Do bees dream of these? (Credit: Sunny_mjx/CC by 2.0)  

In humans, dreams were thought to be a phenomenon of REM sleep, thus limiting the possibility of dreaming to mammals, birds, and (more recently) reptiles; animal groups that exhibit similar eye-fluttering stages of sleep. 

But this is not the case. Over recent decades, studies have revealed that dreaming can also occur during slow-wave sleep, the analogue of honeybees' deep-sleep.

When woken from slow-wave sleep, people often recall basic non-narrative dreams such as a house, faces, or a pet. "[Therefore], if bees dream at all, it would be very basic dreaming," says Zwaka. "A special odour, for example. Or a colour of flowers, like yellow or blue."

The magic well of bee biology is still nowhere near empty.

http://www.bbc.com/earth/story/20160621-do-bees-dream

(NOTE: Even though this article by Alex Riley is dated June 25, 2016, it came through our LACBA Facebook feed today from the Western Apiculture Society and the American Beekeeping Federation - it is too amazing, informative, and has such beautiful images of bees, I simply had to share it with all of you.)

Bees Use a Variety of Senses and Memory of Previous Experiences to Forage for Pollen, Research Suggests

CATCH THE BUZZ-Bee Culture    By Elizabeth Nicholls    November 28, 2016

A honey bee foraging for pollen. Credit: Dr. Elizabeth NichollsBees use a variety of senses and memory of previous experiences when deciding where to forage for pollen, research by the University of Exeter suggests.

The researchers believe pollen-collecting bees do not base their foraging decisions on taste alone, but instead make an “overall sensory assessment” of their experience at a particular flower.

Bees typically do not eat pollen when they collect it from flowers, but carry it back to the nest via special “sacs” on their legs or hairs on their body.

This makes it difficult to understand how bees judge whether the pollen a flower produces is nutritious enough for their young.

Indeed, researchers have been puzzled for a long time as to what exactly bees look for when they collect pollen from flowers.

Co-author Dr Natalie Hempel de Ibarra, expert in insect neuroethology at Exeter’s Center for Research in Animal Behavior, said: “It seems that bees don’t just respond to a single nutritional compound in pollen, such as crude protein content, but to a range of sensory cues in pollen and flowers.

“They also form memories for locations and types of flowers that they have visited which affect their foraging decisions.

“We need more research that considers the behavior and neurobiology of bees to understand when and why they prefer some plants and some pollen over others.

“A breakthrough in this area could advance our efforts in both biodiversity conservation and crop production.”

The review, published in the journal Functional Ecology, examines existing evidence on how bees use their senses, previous experience and — in the case of social bees — feedback from the nest to decide where to gather pollen.

First author Dr Elizabeth Nicholls, a former PhD student at the University of Exeter and now a Postdoctoral Research Fellow at the University of Sussex, said: “Our review is unique in considering pollen foraging from an individual bee’s perspective, asking which senses bees use to decide which flowers are worth visiting.

“In our review we suggest that although bees may taste pollen during collection and use this nutritional information to guide their choices, they are also likely to pay attention to the strong odor and visual appearance of both pollen and the flower itself.

“For bees that live together in colonies, information passed on from the other bees in the nest, either via chemical cues or even special ‘dances’, may also be important in influencing their pollen-collecting behavior.”

The University of Exeter is a major hub for bee and pollination research and currently advertising several postgraduate research projects.

http://www.beeculture.com/catch-buzz-bees-use-variety-senses-memory-previous-experiences-deciding-forage-pollen-research-suggests/#.WDzh_flfTH8.facebook