Category Archives: Apis mellifera

Science and photography, facts and fiction: learn more about honey bees.

The Perfect Design of Honey Bees

This video is a segment of “Silence of the Bees,” a remarkable documentary mini-series that premiered on PBS in October 2007, when the apiculture community was just beginning to suspect the devastating effects that Colony Collapse Disorder would have on honeybee populations.

As the video explains, and as beekeepers know by their own observations, bees are “just this magnificent little engineered thing, just perfect for all the things they can do”:

An architectural marvel, the honeybee’s design is an elegant fusion of form and function. A proboscis for ferreting out nectar stored deep in a flower’s folds. And powerful mandibles for eating, feeding young, and manipulating wax.

Photo: Bee on lavendar via Flickr

Two compound eyes are comprised of 6,900 lenses and covered with sensory hairs for detecting wind speed. Three additional eyes, called ocelli, receive light signals for orientation.

Four wings clasp together with tiny hooks and beat up to 230 times a second.

For defense, a double-edged, serrated sting, which she can use only once — at the cost of her own life.

Hind legs are broadened into special baskets for carrying heavy cargo of pollen to the hive. Feathery hairs coat the body and build up a static charge as the bee flies. When the bee lands on a flower, pollen literally jumps on to her body.

Nature’s award-winning Silence of the Bees was narrated by American actor F. Murray Abraham, winner of the 1985 Academy Award for Best Actor for his role as Antonio Salieri in Amadeus. It was produced by filmmaker Doug Schultz — and if you’re interested in what went on “behind the scenes” in making the documentary, you can read an interview with Doug Schultz at the PBS program website.

Silence of the Bees is available on DVD (packaged together with an equally interesting documentary, Parrots in the Land of Oz). You can get it direct from PBS online or from in the United States and from in Canada.

Glass is Half Empty to Shaken Honey Bees

When people are depressed or anxious, they tend to see their glass as half empty, not half full — but who would expect  the same to hold true of honey bees? New research out of Newcastle University has shown for the first time that bees, when agitated as they would be when disturbed by a predator, show similar signs of pessimism.

To find out something about how honeybees view the world, the researchers “set them up to make a decision about whether an unfamiliar scent portended good or bad things.”

First, the bees were trained to connect one odour with a sweet reward and another with the bitter taste of quinine. The bees learned the difference between the odours and became more likely to extend their mouthparts to the odour predicting sugar than the one predicting quinine.

Next, the Institute of Neuroscience researchers divided the bees into two groups. One group was shaken violently for one minute to simulate an assault on the hive by a predator such as a honey badger. The other group was left undisturbed. Those bees were then presented with the familiar odours and some new ones created from mixes of the two.

Agitated bees were less likely than the controls to extend their mouthparts to the odour predicting quinine and similar novel odours, they found. In other words, the agitated bees behaved as if they had an increased expectation of a bitter taste, the researchers said, demonstrating a type of pessimistic judgement of the world known as a ‘cognitive bias.’

While it may be too soon to claim that honeybees experience “emotions” the way that we humans do, this seems not to be as big a stretch as once we might have imagined!

“What we have shown is that when a honeybee is subjected to a manipulation of its state that in humans would induce a feeling of anxiety, the bees show a similar suite of changes in physiology, cognition and behaviour to those we would measure in an anxious human,” said Dr Geraldine Wright, one of the study’s authors. “In terms of what we are able to measure, a shaken honeybees is no less ‘anxious’ than a lonely dog or a rat in a barren cage.”

For more information, see also:

Agitated Honeybees Exhibit Pessimistic Cognitive Biases
Melissa Bateson, Suzanne Desire, Sarah E. Gartside, Geraldine A. Wright
Current Biology – 2 June 2011 (Vol. 21, Issue 12, pp. 1070-1073)

For stressed bees, the glass is half empty
Newcastle University: Biomedicine: News – 3 June 2011

Photo:  Baukette aus Bienen by Maja Dumat on Flickr

Bees trained to give early warning of plant disease

Remember, back in school, hearing about Pavlov’s dog that learned to drool when it heard a bell ring? That method of “classical conditioning” is how Dr. Andrew Sutherland, a researcher with the University of California Davis Plant Pathology Department, is training honey bees to detect plant disease in agricultural crops.

Here’s the story, straight from Dr. Sutherland:

The problem that we face in California and in the world really is that there are many plant pathogens infecting our crops and many times we apply chemical fungicides to combat that. In our lab we hope to teach honey bees to respond to plant pathogens in the field so that we may detect those plant pathogens and reduce the fungicide applications. Insects in general and honey bees included are excellent vapor sensors and have excellent chemo sensors on their antennas so they’re able to detect organic molecules in the air at the low parts per billion. Bees can be taught to associate an odor with a reward through classical conditioning. First, we restrain the honey bees after collection, we restrain the honey bees inside a harness of sorts such that their heads and antenna are protruding then we expose the bees to the smell of an infected grape leaf or grape berry and we feed the bees at the same. So, in time, the bees learn to associate this odor with the sugar reward. So, the next step is actual detection in the field and this is accomplished through some prototype equipment that’s been designed by my collaborators at Los Alamos National Laboratory. The bees that have been trained are placed inside and when they encounter the smell within the box, they respond and this information is relayed to a computer and we were able to see that indeed we have detected the pathogen in the field. The ultimate goal here is to be able to detect plant pathogens in the field earlier than you can do with your eye so that we have an early warning system and we can better plan fungicide applications to be more efficient in time and space.

See also:
Can bees be trained to prevent plant disease? (Smart
Bees can be trained to detect plant diseases by Jeannette E. Warnert at

Are Honey Bees Hooked on Caffeine and Nicotine?

Have you noticed your honeybees buzzing around the coffee grounds in your compost pile on a warm day in early spring? it turns out, there may be a reason for this common behaviour — the bees might be seeking a hit of caffeine!

Researchers at the University of Haifa-Oranim have learned that bees are attracted to nectar with microscopic amounts of caffeine or nicotine. Is this evolution’s way of getting bees addicted to certain plants that contain those substances?

Flowers produce nectar, a sweet substance composed of mostly sugars, as a way of attracting pollinators to the plant. But some species of plants produce nectar that contains very tiny amounts of substances known to be toxic. The garden perennial Nicotiana, also known as “flowering tobacco,” for example, has tiny amounts of nicotine in its nectar, and caffeine is present in small concentrations in the nectar of citrus flowers, especially grapefruit flowers.

Bees are attracted to nectar with microscopic amounts of caffeine or nicotine… Is this evolution’s way of getting bees addicted to certain plants?

The research team at the Department of Environmental and Evolutionary Biology and the Department of Science Education of the University of Haifa-Oranim, headed by Professor Ido Izhaki, have discovered that bees actively prefer the “addictive” nectar over “clean” nectar.

While it’s difficult to know for sure whether the addictive substances in nectar evolved as a way to make pollination more efficient, they say, the study does suggest that “the plants that survived natural selection are those that developed ‘correct’ levels of these addictive substances, enabling them to attract and not repel bees, thereby giving them a significant advantage over other plants.” Whether the bees actually become addicted to nicotine and caffeine, however, is still a matter for future study.

Photo credit: ‘Spring‘ by: David McLeish
Released under an Attribution-ShareAlike License

The Secret of Hive Temperature Control: Heater Bees

It’s long been understood that different bees have a range of different jobs within the colony. We also know that bees fan their wings to move air around in the hive to regulate the temperature and cluster over the brood to keep it warm.

By carefully regulating the temperature of each pupae, they change the way it develops and the likelihood of the role it will fulfill when it emerges as an adult.

Now, bee researchers have learned special “heater bees” act like a “living radiator” to carefully control the brood temperatures to determine what role the mature bees will fill in the colony — and those empty cells aren’t a problem but a necessary part of how the heater bees function.

According to Dr Jurgen Tautz, head of the bee group at Würzburg University in Germany and author of The Buzz About Bees: Biology of a Superorganism, “By carefully regulating the temperature of each pupae, they change the way it develops and the likelihood of the role it will fulfil when it emerges as an adult.”

Developing bees that are kept at 34°C in their sealed cells will grow up to be housekeeping bees, the ones who clean the hive and feed the brood. Just one degree higher in temperature, and the bees will grow up to be foragers, going out into the fields to find nectar and pollen to bring back to the hive. And it is the “heater bees” who fine-tune the temperature for the developing brood, and effectively decide what roles will be filled by each, making sure that enough bees will be available to fill each important job in the colony.

Now we know that these empty cells are important, then bee keepers can try to avoid selecting for queens that don’t leave these cells empty.

“By creeping into empty cells, one heater bee can transmit heat to 70 pupae around them. It is a central heating system for the colony,” Dr Tautz told the UK Telegraph, in a recent article, Honey bees secret world of heat revealed. “Now we know that these empty cells are important, then bee keepers can try to avoid selecting for queens that don’t leave these cells empty. It can help to ensure that colonies can regulate their temperature properly and have the right mix of individuals.”