One, then some: how to count like a bee


Scarlett Howard, Deakin University and Adrian Dyer, RMIT University

If you were a honeybee, how would you choose where to find flowers? Imagine your first flight out of the hive searching for food. What would you do if you saw flower patches with one flower, or three, or twelve, or twenty?

Our new study, published in the Journal of Experimental Biology, tested honeybees on exactly this question. We wanted to understand how honeybees choose where to forage in environments like greenhouses where our food is pollinated, in local parks, or in our own backyards.

Specifically, our research looked at whether honeybees with no specific numerical training could choose a flower patch based on the quantity of flowers it had.

We found the bees could tell the difference between groups of 1 vs 4 flowers – but not between, say, 4 vs 5. Basically, they couldn’t differentiate between groups of 2 or more flowers.

A honeybee pollinating a strawberry plant flower in a greenhouse.
Adrian Dyer/RMIT University

A mathematical matter of life and death

The ability to tell the difference between two quantities can mean life or death for an animal. “Quantity discrimination” can be vital for survival in tasks including:

  • resource comparison: choosing a larger quantity of food

  • aggressive interactions: choosing to avoid conflicts with larger groups of individuals, and

  • avoiding predators: choosing to stay with a larger group of animals of the same species to reduce your chance of being eaten.

We are gaining a better understanding of quantity discrimination across the animal kingdom. Primates and other mammals, amphibians, reptiles, birds and fish all display some form of quantity discrimination in day-to-day tasks. For example, fish use quantity discrimination to stay in larger groups to reduce the chance of being eaten by a predator.

However, little is known about spontaneous number choices by insects.




Read more:
We taught bees a simple number language – and they got it


How do bees choose where to forage?

Honeybees assess the available flowers based on several factors, including scent, colour, shape and size.

Backyard flowers; which patch to choose if you were a bee?
Adrian Dyer/RMIT University

Honeybees typically visit around 150 individual flowers per flight from the hive to collect resources such as nectar or pollen. For a honeybee, a high quantity of flowers in a single area would mean less energy exertion than having to fly to many flower patches with less flowers.

Using different numbers of artificial flowers, we wanted to test whether individual honeybees could discriminate between a range of quantities, and how they might determine the quality of a flower patch.

Our honeybees were shown pairs of flower quantities ranging from easier number comparisons (such as 1 flower vs 12 flowers) to more challenging scenarios (such as 4 flowers vs 5 flowers).

The experimental set-up (left) and the quantity comparisons (right). Honeybees succeeded at spontaneously discriminating between 1 vs 12, 1 vs 4, and 1 vs 3 flowers, but no other comparisons. The honeybees were trained to associate single yellow dots with sugar water before being shown quantity comparisons.
Scarlett Howard

Interestingly, despite previous findings that trained honeybees can discriminate between challenging quantities and can also learn to add and subtract, the bees performed poorly in our spontaneous number task.

We found they were only able to discriminate between 1 vs 3, 1 vs 4, and 1 vs 12 flowers – wherein they preferred the larger quantity. When 1 flower was an option they succeeded, but confused any comparisons between groups of 2 flowers or more.

This result suggests flower patch choice based on numerical-type cues is difficult for honeybees. And this has implications for how flower displays are interpreted.

A honeybee flies towards three flowers.
Scarlett Howard

With today being World Bee Day, why not take the opportunity to discover what bees are doing in gardens near you. Chances are they’re going to any flower patch with more than one flower, rather than paying much attention to absolute numbers.




Read more:
Bees learn better when they can explore. Humans might work the same way


The Conversation


Scarlett Howard, Postdoctoral research fellow, Deakin University and Adrian Dyer, Associate Professor, RMIT University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Aussie scientists need your help keeping track of bees (please)



The Asian honey bee (Apis cerana) has been found in Cairns. It’s just one of the introduced bees buzzing under the radar.
Tobias Smith, Author provided

Manu Saunders, University of New England; Callum McKercher, University of New England; Mark Hall, Western Sydney University; Tanya Latty, University of Sydney, and Tobias Smith, The University of Queensland

Bees get a lot of good press. They pollinate our crops and in some cases, make delicious honey. But bees around the world face serious threats, and the public can help protect them.

Of more than 20,400 known bee species in the world, about 1,650 are native to Australia. But not all bees found in Australia are native. A few species have been introduced: some on purpose and others secretly hitchhiking, usually through international trade routes.

As bee researchers, we’ve all experienced seeing a beautiful, fuzzy striped bee buzzing about our gardens, only to realise it’s an exotic species far from home.




Read more:
The farmer wants a hive: inside the world of renting bees


We need the public’s help to identify the bees in Australian backyards. There’s a good chance some are not native, but are unwanted exotic species. Identifying new intruders before they become established will help protect our native species.

The European honey bee (Apis mellifera) fuels a valuable honey industry and contributes to agricultural pollination. Other introduced species are far less welcome.
Tobias Smith

Exotic bees in Australia

The European honey bee (Apis mellifera) is the best-known introduced species, first brought to Australia in the early 1800s. It is now well-established throughout the country, with profitable industries built around managed populations.

Other invasive species in Australia are less well known (or loved). The European bumblebee (Bombus terrestris) is present in high numbers in Tasmania, but isn’t thought to be established on mainland Australia.

This bumblebee has caused major harm to native bees in South America, competing for resources and spreading disease.

In northern Queensland, the Asian honey bee (Apis cerana) is established around Cairns and Mareeba, from a single incursion in 2007. The original founding colony is thought to have been a stowaway on a boat that sailed to Cairns from somewhere in southeast Asia or the Pacific, where this bee is widespread.

New Asian honey bee incursions at Australian ports occur almost annually, most recently in Townsville and Melbourne. But swift biosecurity responses have so far stopped them becoming established.

The European bumble bee (Bombus terrestris) lives in large numbers in Tasmania, but is not established on the mainland.
Tobias Smith, Author provided

Why should we care?

Most insects can spread and establish breeding populations before anyone notices them, so it’s important we pay attention to these small intruders.

Introduced species can bring new parasites or diseases into the country that may harm native insects – including our stingless bees that are so vital to crop pollination – or affect the valuable European honey bee industry.

While bumblebees may help commercial pollination in a handful of Australian crops, they and other introduced species can also compete with native species for resources, or spread weeds.

Most resources go to monitoring invasive species with a more dramatic and understood effect on agriculture and the environment. Bees sneak under the radar – but we’re still curious.

Take the African carder bee (Pseudoanthidium repetitum), which arrived in Australia in the early 2000s. Thanks to citizen scientists, we know they are spreading rapidly. In 2014, they were the third most common bee species found in a survey of Sydney community gardens.

An African carder bee spotted in Lismore. They are the third most common bee species in Sydney community gardens.
Tobias Smith, Author provided

Just recently, we found two invasive African carder bees in a backyard in Armidale in northern New South Wales while testing out a new insect monitoring method. There are no confirmed records of this invasive bee in Armidale, although we have seen a few around town since 2017.




Read more:
Bees: how important are they and what would happen if they went extinct?


Although it’s usually exciting to find a new record for a native species, finding an exotic bee where it’s not supposed to be is worrying. How long have they been there, and how many others are there?

The European bumble bee was recently sighted to global biodiversity.

You don’t have to be totally sure what kind of bee you’ve spotted. Just snap some pictures and upload it to a citizen scientist app like iNaturalist with the date and location.
Jean and Fred/Flickr, CC BY

Will you help us keep track?

Anyone can help keep track of potential new invasive species, simply by learning more about the insects in your local area and sharing observations on citizen science platforms such as iNaturalist, or through targeted projects like the African carder bee monitoring project.

You don’t need to be sure exactly what species you’ve seen. Uploading some clear, high-resolution photos, along with the date and location of your observation, will help naturalists and researchers identify it.




Read more:
Wasps, aphids and ants: the other honey makers


You can also participate in events such as the twice-yearly Wild Pollinator Count or local Bioblitzes.

Your efforts can help us detect emerging threats, and add to our records of both native and non-native bees (and other species). Plus it’s a great excuse to get outdoors and learn more about the insect life in your area.


This article was co-written with Karen Retra.The Conversation

Manu Saunders, Research fellow, University of New England; Callum McKercher, PhD Student, University of New England; Mark Hall, Research fellow, Western Sydney University; Tanya Latty, Associate professor, University of Sydney, and Tobias Smith, Ecologist, bee researcher and stingless bee keeper, The University of Queensland

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Bees seeking blood, sweat and tears is more common than you think



File 20190412 76837 1czhl8p.jpg?ixlib=rb 1.1
Known sweat-collecting stingless bees, Tetragonula sp., from the bee family Apidae.
Tobias Smith, Author provided

Manu Saunders, University of New England and Tobias Smith, The University of Queensland

The recent story of four live bees pulled from inside a woman’s eye quickly grabbed people’s attention. News reports claimed the bees were “sweat bees”, the common name for species in the bee family Halictidae.

There are some contradictory and unlikely statements in the many news reports covering this story, so it’s hard to know what actually happened. The images accompanying many reports, which some reporters captioned as the live sweat bees in the Taiwanese woman’s eye, are actually uncredited images from a completely unrelated story – this report by Hans Bänzinger of a stingless bee species (Lisotrigona cacciae) collecting tears from his eye in Thailand.


The Guardian/ Bees (Hymenoptera: Apidae) That Drink Human Tears, in Journal of the Kansas Entomological Society.

All in all, we would consider it extremely unlikely for multiple adult insects to survive inside a human eye for very long. Most halictid bees are too large to get trapped in your eye unnoticed. Female sweat bees also have stingers so you would definitely know straight away!

But whether this story is accurate or not, there are bees who would happily feast on human tears – and blood, sweat and even dead animals. Flower-loving insects like bees and butterflies often seek out other food sources that are at odds with their pretty public image.




Read more:
Can bees do maths? Yes – new research shows they can add and subtract


Un-bee-lievable

So why would bees hang around someone’s eye in the first place? It’s a bit of a myth that all bees only collect pollen and nectar for food. There are bee species all over the world that also feed on the bodily fluids of living and dead animals, including animal honeydew, blood, dead meat, dung, sweat, faeces, urine and tears. This is a source of important nutrients they can’t get from flowers, like sodium, or protein and sugar when floral resources are scarce.




Read more:
Wasps, aphids and ants: the other honey makers


The term “sweat bee” is used colloquially for bees that ingest human sweat as a nutritional resource.

Many people think the term only refers to bees in the Halictidae family. But not all halictid bee species are known to collect sweat, while many species in the Apidae family, particularly stingless bees, are common sweat-collectors in tropical areas around the world. Swarms of sweat-seeking stingless bees can be a nuisance to sweaty humans in tropical places.

And it’s not just sweat; stingless bees have quite diverse tastes and collect many non-floral resources. There are also a few neotropical Trigona species that collect animal tissue as their main protein source, instead of pollen. These species collect floral nectar and make honey, like other stingless bees, but predominantly scavenge on carrion (they are technically know as obligate necrophages).

Vulture bees feed on rotting meat rather than pollen or nectar.
Wikipedia/José Reynaldo da Fonseca, CC BY-SA

Regardless of taxonomy, bees that are attracted to sweat often use other bodily fluids too, like tears. Tear-feeding is such a common behaviour among insects, it has an official name: lachryphagy. Some stingless bees from south Asia, such as the Lisotrigona species mentioned above, are well-known lachryphagous insects, often seen congregating in groups around animal eyes (including humans) to harvest fluids. They don’t harm the animal in the process, although their activity might be a nuisance to some.

In South America, Centris bees are large, solitary apid bees, in the same family as stingless bees and honey bees. These bees are often observed drinking tears from animal eyes; published observations include interactions with caimans and turtles.

Bees aren’t the only insects that regularly drink from animal eyes. Our world-famous hand gesture, the Aussie salute, is designed to deter the common bush flies (Musca species) that hang around our faces on hot days, looking for a quick drink of sweat, saliva or tears. These flies are also commonly seen clustered around livestock eyes on farms.

The feeding habits of butterflies would shock many people who think they are dainty, angelic flower-frequenting creatures. Butterflies are common feeders on dung, carrion, mud and various other secretions, including animal tears. Moths are also well-known nocturnal feeders on animal tears, even while they are sleeping.

Julia butterflies drinking the tears of Arrau turtles in Ecuador.
Wikimedia/amalavida.tv, CC BY-SA

Although most of us wouldn’t like the idea of an insect drinking out of our eyelid, this isn’t the stuff of nightmares. It’s just another fascinating, but little-known, story of how animals interact with each other. From a bee’s perspective, an animal’s eye is just another food source.




Read more:
Catch the buzz: how a tropical holiday led us to find the world’s biggest bee


It produces secretions that provide important nutrients, just like a flower produces nectar and pollen. Although entomologists know this behaviour occurs, we still don’t fully understand how common it is, or how reliant pollinating insects are on different animals in their local environment.

But, while tear-collecting behaviour is normal for many insects, the odds of live bees crawling inside your eye to live are extremely low.The Conversation

Manu Saunders, Research fellow, University of New England and Tobias Smith, Ecologist, bee researcher and stingless bee keeper, The University of Queensland

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Can bees do maths? Yes – new research shows they can add and subtract



File 20181211 76962 cfh85r.jpg?ixlib=rb 1.1
Can we have a count of all the honeycomb cells please?
from www.shutterstock.com

Scarlett Howard, RMIT University; Adrian Dyer, RMIT University, and Jair Garcia, RMIT University

The humble honeybee can use symbols to perform basic maths including addition and subtraction, shows new research published today in the journal Science Advances.

Bee have miniature brains – but they can learn basic arithmetic.

Despite having a brain containing less than one million neurons, the honeybee has recently shown it can manage complex problems – like understanding the concept of zero.

Honeybees are a high value model for exploring questions about neuroscience. In our latest study we decided to test if they could learn to perform simple arithmetical operations such as addition and subtraction.




Read more:
Which square is bigger? Honeybees see visual illusions like humans do


Addition and subtraction operations

As children, we learn that a plus symbol (+) means we have to add two or more quantities, while a minus symbol (-) means we have to subtract quantities from each other.

To solve these problems, we need both long-term and short-term memory. We use working (short-term) memory to manage the numerical values while performing the operation, and we store the rules for adding or subtracting in long-term memory.

Although the ability to perform arithmetic like adding and subtracting is not simple, it is vital in human societies. The Egyptians and Babylonians show evidence of using arithmetic around 2000BCE, which would have been useful – for example – to count live stock and calculate new numbers when cattle were sold off.

This scene depicts a cattle count (copied by the Egyptologist Lepsius). In the middle register we see 835 horned cattle on the left, right behind them are some 220 animals and on the right 2,235 goats. In the bottom register we see 760 donkeys on the left and 974 goats on the right.
Wikimedia commons, CC BY

But does the development of arithmetical thinking require a large primate brain, or do other animals face similar problems that enable them to process arithmetic operations? We explored this using the honeybee.

How to train a bee

Honeybees are central place foragers – which means that a forager bee will return to a place if the location provides a good source of food.

We provide bees with a high concentration of sugar water during experiments, so individual bees (all female) continue to return to the experiment to collect nutrition for the hive.

In our setup, when a bee chooses a correct number (see below) she receives a reward of sugar water. If she makes an incorrect choice, she will receive a bitter tasting quinine solution.

We use this method to teach individual bees to learn the task of addition or subtraction over four to seven hours. Each time the bee became full she returned to the hive, then came back to the experiment to continue learning.




Read more:
Are they watching you? The tiny brains of bees and wasps can recognise faces


Addition and subtraction in bees

Honeybees were individually trained to visit a Y-maze shaped apparatus.

The bee would fly into the entrance of the Y-maze and view an array of elements consisting of between one to five shapes. The shapes (for example: square shapes, but many shape options were employed in actual experiments) would be one of two colours. Blue meant the bee had to perform an addition operation (+ 1). If the shapes were yellow, the bee would have to perform a subtraction operation (- 1).

For the task of either plus or minus one, one side would contain an incorrect answer and the other side would contain the correct answer. The side of stimuli was changed randomly throughout the experiment, so that the bee would not learn to only visit one side of the Y-maze.

After viewing the initial number, each bee would fly through a hole into a decision chamber where it could either choose to fly to the left or right side of the Y-maze depending on operation to which she had been trained for.

The Y-maze apparatus used for training honeybees.
Scarlett Howard

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, bees learnt that blue meant +1 while yellow meant -1. Bees could then apply the rules to new numbers.

During testing with a novel number, bees were correct in addition and subtraction of one element 64-72% of the time. The bee’s performance on tests was significantly different than what we would expect if bees were choosing randomly, called chance level performance (50% correct/incorrect)

Thus, our “bee school” within the Y-maze allowed the bees to learn how to use arithmetic operators to add or subtract.

Why is this a complex question for bees?

Numerical operations such as addition and subtraction are complex questions because they require two levels of processing. The first level requires a bee to comprehend the value of numerical attributes. The second level requires the bee to mentally manipulate numerical attributes in working memory.

In addition to these two processes, bees also had to perform the arithmetic operations in working memory – the number “one” to be added or subtracted was not visually present. Rather, the idea of plus one or minus “one” was an abstract concept which bees had to resolve over the course of the training.

Showing that a bee can combine simple arithmetic and symbolic learning has identified numerous areas of research to expand into, such as whether other animals can add and subtract.




Read more:
Bees get stressed at work too (and it might be causing colony collapse)


Implications for AI and neurobiology

There is a lot of interest in AI, and how well computers can enable self learning of novel problems.

Our new findings show that learning symbolic arithmetic operators to enable addition and subtraction is possible with a miniature brain. This suggests there may be new ways to incorporate interactions of both long-term rules and working memory into designs to improve rapid AI learning of new problems.

Also, our findings show that the understanding of maths symbols as a language with operators is something that many brains can probably achieve, and helps explain how many human cultures independently developed numeracy skills.


This article has been published simultaneously in Spanish on The Conversation Espana.The Conversation

Scarlett Howard, PhD candidate, RMIT University; Adrian Dyer, Associate Professor, RMIT University, and Jair Garcia, Research fellow, RMIT University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Our ‘bee-eye camera’ helps us support bees, grow food and protect the environment



File 20190204 193220 127qf8i.jpg?ixlib=rb 1.1
To help draw bees’ attention, flowers that are pollinated by bees have typically evolved to send very strong colour signals.
Shutterstock

Adrian Dyer, RMIT University and Tanya Latty, University of Sydney

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.

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



Read more:
Bees get stressed at work too (and it might be causing colony collapse)


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.

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.

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

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.

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.
Sue Williams and Adrian Dyer/RMIT University



Read more:
Bees can learn the difference between European and Australian Indigenous art styles in a single afternoon


Building a bee eye camera

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

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.

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

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.

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



Read more:
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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.The Conversation

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

Adrian Dyer, Associate Professor, RMIT University and Tanya Latty, Senior Lecturer, School of Life and Environmental Sciences, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Plants use advertising-like strategies to attract bees with colour and scent


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A honeybee (left), a scarab beetle (middle), and a fly (right) feeding on flowers of the white rock rose in a Mediterranean scrubland.
Aphrodite Kantsa., Author provided

Aphrodite Kantsa, University of the Aegean and Adrian Dyer, RMIT University

Watching plants and pollinators such as bees can teach us a lot about how complex networks work in nature.

There are thousands of species of bees around the world, and they all share a common visual system: their eyes are sensitive to ultraviolet, blue and green wavelengths of the light spectrum.

This ancient colour visual system predates the evolution of flowers, and so flowers from around the world have typically evolved colourful blooms that are easily seen by bees.

For example, flowers as perceived by ultraviolet-sensitive visual systems look completely different than what humans can see.

However, we know that flowers also produce a variety of complex, captivating scents. So in complex natural environments, what signal should best enable a bee to find flowers: colour or scent?

Our latest research uncovered a surprising outcome. It seems that rather that trying to out-compete each other in colour and scent for bee attention, flowers may work together to attract pollinators en masse. It’s the sort of approach that also works in the world of advertising.




Read more:
Want a better camera? Just copy bees and their extra light-sensing eyes


Daunting amount of field work

Classic thinking would suggest that flowers of a particular species should have reasonably unique flower signatures. It makes sense that this should promote the capacity of a bee to constantly find the same rewarding species of flower, promoting efficient transfer of pollen.

So a competition view of flower evolution for different flower species with the same colour – for example purple – would suggest that each flowering plant species should benefit from having different scents to enable pollinator constancy and flower fidelity. By the same logic, flowers with the same scents should have different colours so they’re easily distinguished.

To know for sure what happens requires a daunting amount of field work. The challenges include measuring flower colours using a spectrophotometer (a very sensitive instrument that detects subtle colour differences) and also capturing live flower scent emissions with special pumps and chemical traps.

A wild bee of the genus Anthophora upon making the decision to visit the flowers of purple viper’s bugloss, in a Mediterranean scrubland in Greece.
Aphrodite Kantsa.

At the same time, in order to record the actual pollinator “clientele” of the flowers, detailed recordings of visits are required. These data are then built into models for bee perception. Statistical analyses allow us to understand the complex interactions that are present in a real world evolved system.

Not what we thought

And what we found was unexpected. In two new papers, published in Nature Ecology & Evolution and in Nature Communications, we found the opposite to competition happens: flowers have evolved signals that work together to facilitate visits by bees.

So flowers of different, completely unrelated species might “smell like purple”, whilst red coloured species share another scent. This is not what is expected at all by competition, so why in a highly evolved classical signal receiver has this happened?

The data suggests that flowers do better by attracting more pollinators to a set of reliable signals, rather than trying to use unique signals to maximise individual species.

By having reliable multimodal signals that act in concert to allow for easy finding of rewarding flowers, even of different species, more pollinators must be facilitated to transfer pollen between flowers of the same species.




Read more:
Which square is bigger? Honeybees see visual illusions like humans do


Lessons for advertising

A lot of research on advertising and marketing is concerned with consumer behaviour: how we make choices. What drives our decision-making when foraging in a complex environment?

While a lot of modern marketing emphasises product differentiation and competition to promote sales, our new research suggests that nature can favour facilitation. It appears that by sharing desirable characteristics, a system can be more efficient.

This facilitation mechanism is sometimes favoured by industry bodies, for example Australian avocados and Australian honey. En masse promotion of the desirable characteristics of similar products can grow supporter base and build sales. Our research suggests evolution has favoured this solution, which may hold important lessons for other complex market based systems.

A successful colour–scent combination targeted at attracting bees can be adopted by several different plant species in the same community, implying that natural ecosystems can function as a “buyers markets”.




Read more:
Curious Kids: Do bees ever accidentally sting other bees?


We also know from research that flowers can evolve and change colours to suit the local pollinators. Colours can thus be changed by flowers if instead of bees pollinating flowers, flies, with different colour perception and preferences, dominate the community.

These findings can also prove useful for identifying those colour-scent combinations that are the most influential for the community. This way, the restoration of damaged or disrupted plant-pollinator communities can become better managed to be more efficient in the future.

The ConversationWhen next enjoying a walk in a blooming meadow, remember plants’ strategies. The colourful flowers and the mesmerising scents you experience may have evolved to cleverly allure the efficient pollinators of the region.

Aphrodite Kantsa, Postdoctoral Researcher, University of the Aegean and Adrian Dyer, Associate Professor, RMIT University

This article was originally published on The Conversation. Read the original article.

Pesticide bans might give us a buzz, but they won’t necessarily save the bees


Caroline Hauxwell, Queensland University of Technology

Public pressure is growing in Australia to ban the sale of pesticides called neonicotinoids because of their harmful effects on bees.

The retail chain Bunnings will stop selling the Confidor pesticide brand for homes and gardens by the end of 2018.




Read more:
Ten years after the crisis, what is happening to the world’s bees?


Neonicotinoids along with fipronil, another systemic insecticide that has also been blamed for bee deaths, are widely used in Australia on major crops such as maize, canola and cotton.

Between them they account for up to 30% of global insecticide sales. Will banning these insecticides stop the decline of bees worldwide?

Mites and disease

Insects are in trouble. A recent study found an 80% decline in flying insects, including butterflies, moths and wild bees, in German nature reserves. This has prompted questions about the impact of large-scale intensive agriculture.

Colony collapse disorder, in which worker bees dramatically disappear from honey bee hives, increased hugely in the decade up to 2013, particularly in the United States and Europe. This caused international concern and led to a ban on neonicotinoids and fipronil by the European Union in 2013.




Read more:
Sometimes science can’t see the wood for the bees


However, there are no reports of colony collapse disorder in Australia, according to the Australian Pesticides and Veterinary Medicines Authority, which regulates the use of pesticides and monitors the effect of insecticides on bees. Why not?

We don’t fully understand the causes of colony collapse in honey bees, but it appears that a likely culprit is the Varroa mite and the lethal viruses it transmits. This parasite feeds on both larvae and adult bees, and has been blamed for infecting vast numbers of bees with several viruses including deformed wing virus.




Read more:
Explainer: Varroa mite, the tiny killer threatening Australia’s bees


Australia’s honey bees, in contrast to the rest of the world, are still free of Varroa mites. A CSIRO survey of 1,240 hives across Australia found that deformed wing virus is also not present. The absence of both the mite and the viruses it carries may help to explain why colony collapse has not (yet) been observed in Australia.

Pesticide and fungicides, oh my!

While there is clear evidence of harm to bees from the use of neonicotinoids and fipronil, particularly from drift during application, their role as the direct cause of colony collapse is not proven.

And while they can be harmful, neonicotinoids are not necessarily the biggest chemical threat to bees. Perhaps surprisingly, fungicides appear to be at least as significant.

One study found that bees that eat pollen with high levels of fungicide are more likely to be infected with a pathogen called Nosema. Other research showed that presence of the fungicide chlorothalonil was the best predictor of incidence of Nosema in four declining species of bumblebees. What’s more, the toxicity of neonicotinoids to honey bees doubles in the presence of common fungicides.

This is not to say that Australian bees are safe, or that neonicotinoids are not harmful. Australia has more than 5,000 native bee species, and studies suggest that the main impacts of neonicotinoids are on wild bees rather than honey bees in hives. The combination of widescale use of multiple agrochemicals, loss of plant and habitat diversity, and climate change is a significant threat to both wild and domesticated bees.

And if the Varroa mite and the viruses it carries were to arrive on our shores, the impact on Australia’s honey bees could be catastrophic.

Banning pesticides affects farmers

The EU insecticide ban left Europe’s farmers with few alternatives. Surveys of 800 farms across the EU suggest that farmers have adapted by increasing the use of other insecticides, particularly synthetic pyrethroids, as well altering planting schedules to avoid pests, and increasing planting rates to compensate for losses. Most farmers reported an overall increase in crop losses, in costs of crop protection and in time needed to manage pests.

A ban on fipronil and neonicotinoids would create similarly significant problems for Australian farmers, increasing costs and reducing the efficacy of crop protection. As in Europe, they would potentially increase use of synthetic pyrethroids, organophosphates and carbamates, many of which are even more harmful to bees and other insects.




Read more:
Give bees a chance: the ancient art of beekeeping could save our honey (and us too)


Reliance on a more limited range of insecticides could also worsen the incidence of insecticide resistance and destabilise Australia’s efforts to balance resistance management and pest control with preserving beneficial insects.

Further development of these sophisticated pest management strategies, with emphasis on the use of less harmful alternatives such as microbial and biological controls, offers a route to a more effective, long-term solution to the decline in insects and bee health.

The ConversationA ban on neonicotinoids might give campaigners a buzz, but it might not save the bees.

Caroline Hauxwell, Associate Professor, Queensland University of Technology

This article was originally published on The Conversation. Read the original article.

Ten years after the crisis, what is happening to the world’s bees?



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Bees have been living with the mysterious Colony Collapse Disorder for a decade.
Simon Klein, Author provided

Simon Klein, Université de Toulouse 3 Paul Sabatier and Andrew Barron, Macquarie University

Ten years ago, beekeepers in the United States raised the alarm that thousands of their hives were mysteriously empty of bees. What followed was global concern over a new phenomenon: Colony Collapse Disorder. The Conversation

Since then we have realised that it was not just the US that was losing its honey bees; similar problems have manifested all over the world. To make things worse, we are also losing many of our populations of wild bees too.

Losing bees can have tragic consequences, for us as well as them. Bees are pollinators for about one-third of the plants we eat, a service that has been valued at €153 billion (US$168 billion) per year worldwide.

Ten years after the initial alarm, what is the current status of the world’s bee populations, and how far have we come towards understanding what has happened?

The current status of bees worldwide

Since the alarm was first raised, many countries have created new monitoring methods to judge the status of their bee stocks. As a result we have much more data on bee populations, although coverage is still patchy and differences in survey methods make it hard to compare between continents.

It is clear that bees in the United States are still struggling. Beekeepers can tolerate up to 15% losses of colonies over winter, but the US is massively above this threshold, having lost 28.1% of colonies over the 2015-16 winter.

Canada, by contrast, reported 16.8% losses. This is better, but still above the level of losses at which beekeepers can easily restock.

Only recently have we had data from central Europe. There, honey bees seem to be doing better: 11.9% losses in 2015-16. Meanwhile, in New Zealand surveys only began in the last year and have reported winter loss of 10.7%. Australia does not yet have a countrywide survey of the state of bee colonies.

Fortunes are mixed for bees around the world.
Simon Klein, Author provided

Honey bees are not the only bees that we should care about: wild bees are vital pollinators too. Some plants are pollinated by only one wild bee species, such as the macropis bees that forage on the loosetrife plant.

Unsurprisingly, we have much less data on wild bees than honey bees, and those data we do have point to bigger concerns. For our wild bees we only really have good data for populations that are endangered or that have completely disappeared. Between 2008 and 2013, wild bee diversity in the US dropped by 23%, and a previously common bumblebee species was recently listed as endangered.

Do we understand why?

The good news is that the past decade has seen plenty of progress in understanding the mystery of Colony Collapse Disorder. The bad news is that we now recognise it as a complex problem with many causes, although that doesn’t mean it is unsolvable.

For all bees, foraging on flowers is a hard life. It is energetically and cognitively demanding; bees have to travel large distances to collect pollen and nectar from sometimes hard-to-find flowers, and return it all to the nest. To do this they need finely tuned senses, spatial awareness, learning and memory.

Anything that damages such skills can make bees struggle to find food, or even get lost while trying to forage. A bee that cannot find food and make it home again is as good as dead.

Because of this, bee populations are very vulnerable to what we call “sublethal stressors” – factors that don’t kill the bees directly but can hamper their behaviour.

For solitary species such as the blue-banded bee, difficulty foraging can be a very serious problem.
Simon Klein, Author provided

In a recently published review, we argue that modern agriculture and industry have created a host of sublethal stressors that damage bees’ cognition. For example, diesel fumes and neonicotinoid pesticides both reduce bees’ foraging efficiency by disturbing chemical communications in their brains. Modern intensive agriculture disturbs bee nutrition, which impairs their brain. Climate change interferes with the relationship between bees and the plants on which they feed.

In addition, managed honey bees are afflicted by a range of pests, viruses and predators that have been spread around the world as a side-effect of international trade. The worst is the ominously named Varroa destructor mite, which causes brain development disorders.

What can we do?

At the global level, to preserve our bees we have to improve the environments in which they collect food. Every small action can make a difference. Planting flower borders with bee-friendly flowers in your garden can provide food for both wild and domestic bees. You can reduce or eliminate the use of herbicides or pesticides when gardening. Even mowing the lawn less often can help bees out.

You could install a native bee hive or insect hotel. Another tempting option is to buy local honey, which often has a more distinctive flavour than mass-produced versions.

In Australia, we are fortunate in that our bees seem to be doing better than many other parts of the world. The Varroa mite has not yet invaded our shores, and in many areas bees can access pesticide-free bushland (although unlike Europe, Australia has not yet banned use of neonicotinoids in agriculture).

Australia also has an incredibly rich diversity of wild native bees: up to 1,600 different species, including our emblematic stingless bees. Even so, to protect this diversity we need better surveys of how these species are doing.

Ten years on from the alarm over disappearing bees, it is fair to say we now know the nature of the problem and what can be done to fix it. It’s up to us to take the steps needed to sustain these precious pollinators of our food for the future.

Simon Klein, Doctorant, Université de Toulouse 3 Paul Sabatier and Andrew Barron, Associate Professor, Macquarie University

This article was originally published on The Conversation. Read the original article.