Scroll down to find an array of stories showcasing recent research & news of honey bee behavior. Have a story to share? Please click here to contact us!
“Worker bees ‘know’ when to invest in their reproductive future”: 20 Aug 2014, Science Daily
Once a bee colony’s population hits 4000, this number seems to “trigger” building drone comb. Cornell University neurobiologists studied this, noting that “reproduction isn't always a honeybee colony's top priority” – “survival and growth” is, especially early in the colony’s growth. Once the colony reaches a certain threshold, “its workers start investing in reproduction,” with drone comb the first step in that process. The researchers wanted to learn “precisely which colony features kick-start this key process of building drone comb. Is it the number of workers in the colony? Is it the total area of worker comb in the colony? Is it the amount of brood in the colony? Or perhaps it's the size of the colony's honey stores?” The researchers tested each of these factors separately and found “that while every colony built worker comb (non-reproductive comb), not every colony built drone comb (reproductive comb). In fact, only an increase in the number of workers stimulated the workers to start constructing drone comb. This was seen whenever colonies contained 4,000 or more worker bees.”
How, then, would one worker bee “'know' how many other workers there are in its colony”? Possibly feeling crowded in the hive tells them. "Colonies with more workers built a greater proportion of drone comb, but colonies with more comb, more brood, or more honey stores, did not do so . . . we estimate that a colony needs approximately 4,000 workers to invest in building drone comb." The researchers’ next steps will focus on this. To read more, visit: http://www.sciencedaily.com/releases/2014/08/140820091609.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily+%28Latest+Science+News+--+ScienceDaily%29 .
“Venom Gets Good Buzz as Potential Cancer-fighter”: 11 Aug 2014, American Bee Journal
Scientists have found a way that bee, snake, and scorpion venom could be used in “cancer-fighting drugs”: the new method “target[s] venom proteins specifically to malignant cells while sparing healthy ones, which reduces or eliminates side effects that the toxins would otherwise cause.” The venom toxins would be packaged in “tiny nanometer-sized particles to treat breast cancer and melanoma cells in the laboratory." Because these particles are “camouflaged from the immune system, [they can] take the toxin directly to the cancer cells, sparing normal tissue." Melittin, a substance in honey bee venom, stops multiplication of cancer cells, but since bees make very tiny quantities of venom, it must be synthesized. Next, this new method will be tested in rats and pigs, then in human patients within the next 3 to 5 years.
To read more, visit: http://us1.campaign-archive1.com/?u=5fd2b1aa990e63193af2a573d&id=ed92385685&e=e9ff21e0bb . To see a video on this research, visit: http://www.youtube.com/watch?v=GRsUi5UrH7k&feature=youtu.be .
“Vasculature of the hive: How honey bees stay cool”: 23 July 2014, Science Daily
A new Tufts University study has shown that adult honey bees share the work of keeping colony temperatures low enough to prevent brood from being overheated. The worker bees “dissipate excess heat within a hive in process similar to how humans and other mammals cool themselves through their blood vessels and skin.” The study supports the theory that honey bee colonies are “superorganism[s] – entit[ies whose] many members carry out specialized and vital functions to keep the whole functioning as a unit.” The study notes that “[f] or healthy development, the youngsters must be maintained between 32 degrees Celsius, or 89.6 degrees Fahrenheit, and 35 degrees Celsius, or 95 degrees Fahrenheit. In contrast, adults can withstand temperatures as high as 50 degrees Celsius, or 122 degrees Fahrenheit.” Those more heat-tolerant adults work to cool the hive for the developing young.
How do the bees do this? “When temperatures dip, worker bees create heat by contracting their thoracic muscles, similar to shivering in mammals. To protect the vulnerable brood when it's hot, workers fan the comb, spread fluid to induce evaporative cooling, or -- when the heat stress is localized -- absorb heat by pressing themselves against the brood nest wall (a behavior known as heat-shielding).” This was known, but the Tufts study found out how the workers discharged that excess heat: “[T] he worker bees pressed their bodies against the heated surfaces near the brood. Like insect sponges, they absorbed the heat, which lowered temperatures. . . . [U]sing thermal imaging, the scientists observed that temperatures increased peripheral to the heated regions of the hive as the brood nest began to cool. The thermal images clearly showed that the bees had physically moved the absorbed heat in their bodies to previously cooler areas of the hive." The workers did this so efficiently that “[w]ithin 10 minutes of cooling, temperatures in the active hives were down to safe levels.”
Two new studies express conflicting findings about the healthfulness of feeding honey to bees:
“Scientists Track Gene Activity When Honey Bees Do and Don't Eat Honey” 18 July 2014, American Bee Journal and Bee Culture Magazine
New research shows “significant differences” in bees’ gene activity based on what they eat. The researchers studied “fat body” tissue – which, like our human liver, processes food and filters toxins – in forager bees, chosen because they have “higher metabolic rate and less energy reserves . . . . than their hive-bound nest mates -- making the foragers much more dependent on a carbohydrate-rich diet.”
Bees fed honey – as opposed to high fructose corn syrup (sucrose) – “had a very different profile of gene activity in the fat body than those relying on HFCS or sucrose.” Genes “that were activated differently in the honey-eating bees have been linked to protein metabolism, brain-signaling and immune defense.”
The study supports University of Illinois research May Berenbaum’s 2013 findings that “some substances in honey increase the activity of genes that help the bees break down potentially toxic substances such as pesticides.” Further, these results " parallel suggestive findings in humans . . . in both bees and humans, sugar is not sugar -- different carbohydrate sources can act differently in the body."
To read more, visit: http://home.ezezine.com/1636/1636-2014.07.18.07.47.archive.html and http://us1.campaign archive1.com/?u=5fd2b1aa990e63193af2a573d&id=d031538bf5&e=e9ff21e0bb.
“Feeding Honeybees Honey May Increase Mortality”: 27 June, 2014, BeeInformed.org
The Bee Informed Partnership survey results from 2011-12 and 2012-13 have turned up a surprising suggestion: “Feed your honeybees candy, dry sugar, high fructose corn syrup (HFCS), honey, sugar syrup, wet supers or nothing at all, it doesn’t matter, you get the same colony loss, in this case, about 23%.” The survey data showed that dry modes of feeding – candy boards and dry sugar – had slightly lower losses than those feeding wet modes, including – surprisingly – frames of honey. In 2012-13, the survey – this time sampling about 557,000 colonies – found that “[t] hose who chose to feed their colonies lost about 45% while those that chose not to feed carbohydrates lost 36%.”
It should be noted that these data come from surveys rather than direct experimentation; it should also be noted that the honey feeding results may be connected to feeding bees honey produced by other colonies.
To read more, visit: http://beeinformed.org/wp-content/uploads/2013/08/title-carbohydrate-feed.pdf and http://beeinformed.org/wp-content/uploads/2014/03/6.CarbohydrateFeedSummary.pdf
“Bees have an inbuilt SAT NAV: Insects don't use the sun as a compass, but build a 'mental map' to navigate, study reveals”: 2 June 2014, UK Daily Mail
Bees do not, after all, orient home by the position: researchers at the University of Auckland have found that, instead, bees actually “create a ‘mental map’ like humans and other animals.” Despite their small brains and lack of navigating structures like the human hippocampus, bees can “rely on a built in ‘sat nav’ system to find their way around.” The study set back the body clock of bees by 6 hours and then “fitted them with tiny radar transponders” to see whether they could navigate home from a strange place, reasoning “that if the bees did rely on the sun as a compass, then the alteration to their body clocks would disrupt their ability to find their way home.” However, the bees whose circadian rhythms had been set back “returned with similar speed and accuracy as those that had not been put to sleep.” This led the researchers to conclude that “bees may navigate by a mental terrain map in addition to learned sun-compass directions.” To read more, visit: http://www.dailymail.co.uk/sciencetech/article-2646418/Bees-inbuilt-SAT-NAV-navigate-study-reveals.html#ixzz33ujYsXgu .
“Waggling Bees Give Their Verdict on a Landscape”: 26 May 2014, The New York Times
A research team at the University of Sussex measured bees’ waggle dances to determine whether the $ 56 billion-plus spent over the past 10 years to improve environmentally friendly landscaping worked or not. Since bees from one colony “can cover about 40 square miles of territory,” it was more efficient to analyze over 5000 waggle dances of bees than to try to have people cover the ground. “The bees’ verdict”: nature reserves were superior to tracts of land that had implemented better landscaping practices. The researchers think this was “probably because although they were specially planted with nectar-rich flowers like clover and bird’s-foot trefoil, these tracts were regularly mowed.” To read more, visit: http://www.nytimes.com/2014/05/27/science/waggling-bees-give-their-verdict-on-a-landscape.html?emc=eta1&_r=0 .
“Bee Biodiversity Boosts Crop Yields”: 9 MAY 2014, American Bee Journal
When different kinds of bee species pollinate blueberries, the result is more seeds, bigger berries, and substantially higher fruit production, according to a new study from North Carolina State University. Dr. Hannah Burrack says the study shows "the functional role of [bio]diversity." Burrack and colleagues studied “honey bees, bumble bees, southeastern blueberry bees, carpenter bees and a functionally similar collection of species that they termed small native bees.” For each added bee species, “farmers saw an increase of $311 worth of yield per acre. . . . For North Carolina blueberries as a whole . . . the benefit of each group [is estimated at] approximately $1.42 million worth of yield each year."
Co-author Dr. David Tarpy suggests that different bees’ behavior, partly in response to weather, leads to these benefits: blueberry bees don’t mind the rain, but honey bees work best in the sun. More bee species means fewer days in which no pollination takes place. Next steps will explore “what role crop management can play in fostering bee diversity at crop sites.”
To read more, visit: http://us1.campaign-archive2.com/?u=5fd2b1aa990e63193af2a573d&id=4151881f82&e=e9ff21e0bb
“A Queen Bee’s Secret, Pinpointed”: 20 Jan 2014, The New York Times
It’s not only bees whose queens suppress other females in their colonies – wasps and ants do this, too. A Belgian study has shown that “pheromones . . . specific to queen wasps, bumblebees and desert ants keep workers sterile while in their presence.” These pheromones stop worker insects from developing ovaries, and stop them from laying if they do manage to develop ovaries. The researchers found that queens “overproduced certain chemicals” which then were “administered . . . to workers in the absence of a queen. Those insects remained sterile, while workers separated from their queen and not given the chemicals regenerated their ability to reproduce.” To read more, visit: http://www.nytimes.com/2014/01/21/science/a-queen-bees-secret-pinpointed.html?emc=eta1
“Molecular evolution of genetic sex-determination switch in honey bees: 5 amino acid differences separate males from females”: 12 Dec 2013, American Bee Journal E-zine
How did honey bees evolve their system of haplodiploid sex determination - by which the queen does not fertilize drone eggs? Studying 76 genotypes of honey bees, researchers found that in bees, there is just one “gene locus responsible for sex determination,” and that bees recombine their genetic material in the course of reproduction more than other animals examined. In trying to determine which genetic alleles drove sex determination, they had to re-examine what alleles are, and how exactly alleles must match up when recombined. Just “five amino acid differences” drive the entire process of “creat[ing] femaleness through the complementary sex determiner (csd) gene – the control switch.” Further, the researchers learned that just “three amino acid differences spanned the balance between lethality and induced femaleness,” and that “incomplete penetrance may be the mechanism by which new molecular switches can gradually and adaptively evolve.” The original study, "Gradual molecular evolution of a sex determination switch in honeybees through incomplete penetrance of femaleness," was published in the December issue of Current Biology. To read more, visit: http://us1.campaign-archive2.com/?u=5fd2b1aa990e63193af2a573d&id=76c13cbb8b&e=e9ff21e0bb
“Secrets of bee honeycombs revealed”: 25 July, 2013; Phys.org
The astonishing mechanical perfection of honey bee comb has, literally for millennia, made people wonder whether bees need “uncanny ability - "forethought," according to Pappus of Alexandria in 4 AD – to perform mathematical calculations or the magical quality to measure lengths and angles.” The Cardiff University School of Engineering has found the mechanism by which bees make these characteristic shapes: “cells in a natural honeybee comb have a circular shape at "birth" but quickly transform into the familiar rounded hexagonal shape while the comb is being built.” The “heater” bees inside the hive make the wax “semi-molten”: at 45 degrees Centigrade, the wax begins “to flow slowly as an elastic liquid,” and “then gets pulled into hexagonal cells by surface tension at the junctions where three walls meet.” The engineers commented: "We cannot... ignore, nor can we not marvel at the role played by the bees in this process by heating, kneading and thinning the wax exactly where needed."
To read more, visit: http://phys.org/news/2013-07-secrets-bee-honeycombs-revealed.html
“Do You Have a Sweet Tooth? Honey Bees Have a Sweet Claw”: 4 Feb 2014, American Bee Journal Ezine
A new French study shows how honey bees process information that they taste using claws on their forelegs. Sensilla, “hair-like structures . . . that contain receptor nerve cells,” help many insects taste. Honey bees have sensilla on their mouth parts, antennae, and the last joints of their legs, called tarsi. The study found that bees assess what they learn from their front tarsi when choosing whether or not to feed. The double claw at the end of the honey bee tarsus targets sugary tastes, whereas the tarsomeres, the segments before the claws, target saline solutions. Given that bees’ mouth parts and antennae contain more sensilla than their tarsus, tarsal sensitivity is “impressive,” according to the researchers: “The claw's sense of taste allows workers to detect nectar immediately when they land on flowers. Also, bees hovering over water ponds can promptly detect the presence of salts in water through the tarsomeres of their hanging legs." When the bees get clashing signals from their forelegs – say, a nice hit of sucrose from the left, but something noxious from the right, then first impressions prevail: bees “weigh” both, but their response – to feed or to move on - tends to be governed by information they process first.
To read more, visit: http://us1.campaign-archive2.com/?u=5fd2b1aa990e63193af2a573d&id=1c86064c4b&e=e9ff21e0bb
“Honey bees demonstrate decision making process to avoid difficult choices”: 8 Jan. 2014, Bee Culture’s Catch the Buzz E-zine
When faced with tough choices, but not given enough information to make a good decision, honey bees act like people – they “opt out” of making commitments, according to a recent Australian study. Researchers made bees “learn a rule to match a combination of shapes with nectar”: if they identified the target correctly, they got nectar as a reward, but wrong identifications got a punishment of a “bitter tasting solution.” The added condition: the bees could refuse to make an identification at all - like students avoiding a negative score on an ambiguous SAT question – and thus forgo the possibility of the sweet reward, but avoid the threat of the bitter punishment. The tougher the challenge, the more often the bees “opted out.” Whether non-humans could weigh “their level of certainty about a choice before taking action” has long been argued: dolphins, dogs, and rats have been tested, but “this study is the first to demonstrate that even insects are capable of making complex and adaptive decisions.”
To read more, visit: http://home.ezezine.com/1636/1636-2014.01.08.11.14.archive.html
“Can bees be trained to sniff out cancer? Designer Susana Soares has created a glass apparatus that harnesses bees' sense of smell to detect disease”: 14 Dec 2013, Smithsonian.com
A honey bee’s keen sense of smell can home in on an odor generated by just a few molecules: bees can learn to sniff out chemicals “from methamphetamines to ingredients in explosives.” Now scientists have shown that bees can sniff out tuberculosis, diabetes, and possibly even cancer. Certain diseases – lung cancer is one – generate “odorous compounds” that manifest in blood and urine – and breath. A British product designer has invented a glass chamber into which a patient could exhale: bees taught “to associate a specific chemical odor with a food reward” will gather around that exhalation if it contains that target odor. Some studies have trained mice or dogs to sniff out cancers, but bees’ antennae make them even more sensitive to target odors, especially when there are many competing signals, as there are in human breath. Dogs, with their legendary sniffers, only got it right in 71% of tests – but bees scored 98%. Not only that, the bees were trained inside ten minutes.
Soares’ glass chamber has been field tested and turned up a diagnosis of diabetes later confirmed by doctors. Sadly, though, no medical companies see enough profitability in honey bee cancer or other disease screening to try making it more widely accessible. For now, the project remains a “purely academic exercise” that shows a “symbiotic relationship” between people and bees. A similar project was conducted with wasps, who proved able to sniff out bedbugs.
To read more, visit: http://www.salon.com/2013/12/14/can_bees_be_trained_to_sniff_out_cancer_this_designer_says_yes_partner/?source=newsletter
“Who’s Best At What, When and Where Finally Gets Measured,” 10 Dec 2013, “Catch the Buzz”Bee Culture e-zine
Scientists at North Carolina State University have suggested guidelines “for assessing the performance of pollinator species in order to determine which species are most important and should be prioritized for protection.” Their goal has been creating “a set of metrics” that allow researchers to compare apples to apples when they evaluate pollinator efficiency across crop types and agricultural regions.
These metrics are: “First, single-visit efficiency, which measures the number of seeds produced when one bee visits one flower. Second is abundance, which measures the number of each type of bee observed in a study area. Third is inclement weather behavior, which tracks how active a bee species is during cool, cloudy and/or windy weather. Fourth is visitation rate, or the number of flowers that a bee visits while foraging, and the amount of time it spends at each flower.” Lead researcher Hannah Burrack commented, “The perfect bee would produce a lot of seeds and visit a lot of flowers, even in poor weather – and there would be a lot of them. But as far as we know, the perfect bee doesn't exist."
Blueberry bushes were the target crop for the pilot study: it found that though native bees “had extremely high single-visit efficiency rates and were active during inclement weather,” their visitation rates were relatively low, as was their abundance. NC State Entomology professor David Tarpy notes, "This highlights the importance of incorporating multiple metrics. Because researchers looking only at visitation rates or abundance may think the small native species are unimportant, when they actually appear to be important pollinators for blueberry growers."
The paper is titled "Multiple Criteria for Evaluating Pollinator Performance in Highbush Blueberry (Ericales: Ericaceae) Agroecosystems," published online Nov. 25 in the journal Environmental Entomology.
To read more, visit: http://home.ezezine.com/1636/1636-2013.12.10.09.12.archive.html
“Queen Bee's Honesty Is the Best Policy for Reproduction Signals”: Science Daily, 13 Nov 2013:
Nationwide, beekeepers have observed that their queens don’t last as long as they used to – weeks or months, not years. A new study by scientists from Penn State, North Carolina State, and Tel Aviv University may have found out why: pheromonal signals that queens send to workers give “an honest message about their reproductive status and quality.” Through pheromones, queens tell workers not only whether they have been mated, but how well – meaning with how many drones. As earlier studies have shown, “promiscuous” queens bring greater genetic diversity to their colony, making the colony healthier. If bees can tell that a queen is poorly mated, they can supersede her – and that could explain high queen turnover.
The researchers artificially inseminated queens with varying amounts of semen or saline. Workers responded much more strongly to pheromone extracts from queens that had been inseminated with more semen than less, and even preferred extracts with low semen to those that had saline instead. According to the research team, "these results suggest that queens are signaling detailed and honest information about their mating state and reproductive quality to workers, and workers are capable of adjusting their behavior accordingly.” That behavior adjustment can include supersedure, which sets back the colony’s development: weeks will pass before a new, laying queen can replenish the forager population, and that assumes that the new queen survives her mating flight.
The study also showed that queen pheromones regulate the rate at which workers mature from nurse to forager: this suggests that if the quality of the queen’s pheromones is weaker, the entire colony could be affected, perhaps leading to smaller forager populations. The next step in the study will be to explore “effects of viruses, pesticides and poor nutrition on queen pheromone quality to see if the queen also is providing workers with information about her health . . . the more we know about what affects the queen's health the better chance we will have of creating high-quality queens and disease-resistant stocks of honey bees," the researchers said.
To read more, visit: http://www.sciencedaily.com/releases/2013/11/131113182549.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily+%28ScienceDaily%3A+Latest+Science+News%29. Also, see “Queen bees tell the whole hive about their sexual flings,” 14 Nov. 2013, Los Angeles Times: http://www.latimes.com/science/sciencenow/la-sci-sn-queen-bees-sex-20131113,0,5798275.story#axzz2kjKtaKXU
“Sneaky breeders make sons,” 15 Aug 2013, Nature:
Australian entomologists have observed an exception to the rule that worker bees don’t reproduce. We’re familiar with the phenomenon of the “laying worker,” a problem that signals a queenless hive, but the researchers found that workers actually lay 4.2% of drones – 40 times more than had been thought up till now – and that workers increase this production to 6% when queen cells are present in the hive, either prior to supersedure or swarming. The researchers hypothesize that workers may increase their rate of laying to improve the odds that there will be sufficient drones to mate new queens.
To read more, visit: http://www.nature.com/nature/journal/v500/n7462/full/500257e.html . Original study published in Molecular Ecology, Vol. 22, pp 4298-4306. Nature reference: Nature 500, 257 (15 August 2013) doi:10.1038/500257e. Published online 14 August 2013.
“Diesel Exhaust Stops Honeybees from Finding the Flowers They Want to Forage,” 3 Oct. 2013, ScienceDaily.com; “Bees' Foraging for Flowers 'Hampered by Diesel Exhaust,'” 3 Oct, BBC News:
We’re used to hearing about the negative effects of pesticides on honey bees, but we don’t often consider how common pollutants like car exhaust may affect them. A new study by the University of Southhampton has found that when exposed to chemicals in diesel exhaust, bees’ capacity to identify floral odors diminishes significantly. When pollution stops bees from recognizing floral odors, their ability to forage efficiently may be affected and, by extension, pollination and “global food security.”
The researchers mixed 8 chemicals from rapeseed flowers with – in one condition – clean air, and - in the other condition - with air mixed with diesel exhaust, including NOX gases (nitrogen dioxide). 2 of those floral chemicals disappeared within 60 seconds of exposure to diesel exhaust; the other 6 dropped substantially in volume. Honey bees could not recognize the floral odor in this mixture; in contrast, clean air did not affect the floral odor or change normal bee behavior.
The study taught bees to link individual chemical smells with a food reward of sugar syrup. Bees stick out their tongues in response to tasting the sugar – what they do when they find nectar on a flower. Once bees are trained to respond to a particular scent, scientists can use this “proboscis extension reflex (PER) test” to determine how they respond to that scent when “depleted by exposure to NOx [the reactive chemical in diesel exhaust].” Bees exposed to the air mixed with diesel exhaust did not stick out their tongues, thus showing no recognition of the floral odor.
According to Dr. Tracey Newman, lead neuroscientist on the project, "Honeybees have a sensitive sense of smell and an exceptional ability to learn and memorize new odours. NOx gases represent some of the most reactive gases produced from diesel combustion and other fossil fuels, but the emissions limits for nitrogen dioxide are regularly exceeded, especially in urban areas. Our results suggest that that diesel exhaust pollution alters the components of a synthetic floral odour blend, which affects the honeybee's recognition of the odour. This could have serious detrimental effects on the number of honeybee colonies and pollination activity."
To read more, visit: http://www.sciencedaily.com/releases/2013/10/131003093035.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily+%28ScienceDaily%3A+Latest+Science+News%29
Unraveling the Pollinating Secrets of a Bee’s Buzz (11 July 2013, The New York Times)
Bumblebees are “buzz pollinators”: they deploy their buzz literally to vibrate pollen right out of a flower. Fertilization, to a bumble, is just a side effect of dinner. Scientists have been investigating how buzz pollination got its start, and why some plants evolved to depend on it rather than wind or more direct insect pollination. It’s more usual for plants to secrete nectar that attracts pollinators, who then pick up pollen and leave it behind, fertilizing other individual plants. Cranberries, tomatoes, potatoes, and some 20,000 others have only pollen to attract pollinators. Fortunately for these plants, bumblebees and other pollinators that need pollen will seize the flower “with its jaws and start [ ] vibrating hundreds of times a second,” thus accessing the pollen “tucked deep inside.”
“It has to hold on, because the vibrations are so strong that otherwise it could come flying off the flower,” according to one of the project scientists. The bees also make a striking sound as they buzz pollinate: “It sounds like a bee is giving you a raspberry,” in the words of one of the other researchers, Stephen Buchmann of the University of Arizona. Buchmann comments, “The bees are turning themselves into living tuning forks,” to release the pollen, which gets enough momentum to “blast out in a cloud that coats the bee.” Though the bees’ goal is to feed their larvae back at the nest, the resulting mess means that excess pollen sticking to the bees’ hairs can still fertilize plants.
Many questions remain – how plants evolved this mechanism for fertilization, and why honey bees can’t buzz-pollinate, though bumbles can. Since bumblebees are declining like honey bees and other pollinators, scientists want to learn more. “‘We could live just on wind-pollinated plants like wheat and barley and millet,” said Dr. Buchmann, wearily listing each food, “but it would be a pretty bland, nasty diet.’”
To read more, click here; complete URL: http://www.nytimes.com/2013/07/11/science/unraveling-the-pollinating-secrets-of-a-bees-buzz.html?emc=eta1&_r=0
“What is it about bees and hexagons?” (Robert Krulwich, NPR, May 16, 2013)
Why do bees build comb exclusively in the shape of hexagons? Scientists have been asking this question since, literally, ancient Rome, when the scholar Varro proposed the “Honeybee Conjecture," suggesting that bees have a reason: perhaps hexagons can hold more honey, or cost less wax to construct than other shapes.
Physicist/writer Alan Lightman has run with Varro’s conjecture, positing that the way bees build comb – simultaneously, with no workers taking down time – they chose a shape that fits together with maximum efficiency, leaving no gaps. Lightman notes that “only three geometrical figures with equal sides . . . can fit together on a flat surface without leaving gaps: equilateral triangles, squares and hexagons."
Why the hexagon, then? Varro argued that bees choose it for its compactness – and since it costs bees “8 ounces of honey to produce a single ounce of wax . . . compactness matters.” In 1999, Thomas Hales, a professor of mathematics at the University of Michigan, made a mathematical proof that the hexagon actually is more compact in construction than either squares or equilateral triangles. So . . . now we know what bees were born knowing.
To read more, click here; complete URL: http://www.kplu.org/post/what-it-about-bees-and-hexagons
New study shows that bees’ “jobs” in hives can be changed by chemical signals when colonies must adapt to new conditions: Popular Science, 10 Apr 2013:
New research has shown that the different “jobs” bees do in the hive are determined by “chemical tags attached to the bees’ DNA.” These tags can either instigate or reverse specific bee behaviors. The capacity of nurse bees to change a larva’s destiny by feeding royal jelly, making her into a queen instead of a worker, is well known, but now Arizona State scientists have found that chemical tags can activate other substantial changes. For example, foragers make up about a third of the colony’s workforce, but if there is a sudden nectar flow, “young bees that would normally become nurses immediately develop into foragers, a switch reflected by changes in their epigenetic tags.” Another example was discovered in swarming behavior, when “some foragers and free-agent bees will . . . shift to nursing.”
However, there are limits to how far the chemical commands can change bee behavior: “[i]n a lab experiment, after half of a hive’s population was taken away, only 10 percent of foragers became nurses. Scientists say that fragility may keep many foragers from making the switch. Foragers are programmed to be frail in order to protect the colony: Rather than bring infections or toxins back to the hive, they typically die out in the field.” The researchers aren’t sure what activates the chemical tags to spark these epigenetic changes, but one speculation is that “pheromones exuded by the forager bees might play a role.”
To read more, click here, or visit: http://www.popsci.com/science/article/2013-03/honeybee-society
“Bees gravitate to caffeine in nectar” (7 Mar 2013, New York Times):
While it’s not news that plants use sugars, fragrances, and other chemicals to attract pollinators, new research shows that some plants have nectar that is naturally infused with caffeine, which “enhances the learning process for bees,” making them more likely to pay those plants a repeat visit. “‘The plant is using this as a drug to change a pollinator’s behavior for its own benefit,’” according to researchers at Newcastle University in England.
Although some types of citrus and coffee plants contain caffeine in “toxic concentrations” in leaves – a feature that deters predators – their nectar contains lower amounts, like a weak cup of coffee. The scientists tested to see whether bees could connect an odor and a reward (sugar water plus caffeine) and found that“[i]f you put a low dose of caffeine in the reward when you teach them this task, and the amount is similar to what we drink when we have weak coffee, they just don’t forget that the odor is associated with the reward.” Whether bees are attracted to beekeepers who are serious coffee drinkers was not addressed in the study.
To read more, click here, or visit: http://www.nytimes.com/2013/03/08/science/plants-use-caffeine-to-lure-bees-scientists-find.html?emc=eta1&_r=0
“Honey, It's Electric: Bees Sense Charge On Flowers” (NPR.org, 22 Feb 2013):
As Michael Pollan noted in The Botany of Desire, vibrant floral colors and scents that delight our senses do a more important job: attracting pollinators. A new study has discovered another way that flowers flag down bees: their electric field. Working with bumblebees, scientists discovered that “flowers have a slight negative charge relative to the air around them,” and that “when bees are flying through the air, just the friction of the air and the friction of the body parts on one another cause the bee to become positively charged. . . . When a positively charged bee lands on a flower, the negatively charged pollen grains naturally stick to it.”
Researchers tested this by designing a field of fake steel flowers – some filled with sugar water, some with quinine, then tested how bees responded to a charge placed on the sweet ones. The bumblebees adapted, preferring the charged flowers. But why? The study showed that the “plant's electric field is changed by the proximity of that positively charged bee. And once the bee leaves, the field stays changed for 100 seconds or so. That's long enough for the altered field to serve as a warning for the next bee that buzzes by. She won't stop to investigate a flower that's already been visited.” This marvelous efficiency serves both flowers and bees brilliantly.
To read more details, visit: http://www.kqed.org/news/story/2013/02/22/116796/honey_its_electric_bees_sense_charge_on_flowers?source=npr&category=science. To read the complete study in Science – which notes that an older study shows honey bees, too, carrying a charge, and that follow-up research focused on honey bees is starting - click here.
“Honey bees are more effective at pollinating almonds when other species of bees are present”:
On 11 Jan 2013, Phys.org reported that new research from central California shows that honey ees do a better job pollinating the almonds if they have help from native bees like blue orchard bees, bumblebees, carpenter bees, and sweat bees. Entomologists from UC Davis report that "[i]n orchards with non-Apis (non-honey bees), the foraging behavior of honey bees changed and the pollination effectiveness of a single honey bee visit was greater than in orchards where non-Apis bees were absent," suggesting that more pollinators make better pollinators, thus highlighting how important preserving diversity among pollinator species is.
Next steps: "Now that we know about bee behavior—that they move more between orchard rows when non-Apis bees are around—we need to study the reason why they move . . . One route we will be exploring is the chemical footprints that the bees are leaving on the flowers." To read the full study, "Synergistic Effects of Non-Apis Bees and Honey Bees for Pollination Services," visit: http://phys.org/news/2013-01-honey-bees-effective-pollinating-almonds.html#jCp. To see their video - "Can Wild Pollinators Contribute, Augment and Complement Almond Pollination in California" - visit: admin.na4.acrobat.com/_a841422360/p37649788/
“Researchers identify new components of the epigenetic 'code' for honey bee development”
11 Dec 2012: British and Australian scientists have new evidence that may explain why honey bees respond so sensitively to changes in their environment – including pesticides. They’ve discovered bees’ “histone codes,” markings on proteins underlying DNA, which can be triggered by “nutrition and environmental factors.” These codes essentially turn genes on or off: for example, when nurse bees feed royal jelly to a larva, the jelly may activate a histone code that “turns on” the genes and makes that larva a queen rather than a worker. Though scientists have known that people have these histone codes, they’ve never before been found in bees.
Next, researchers will try to find out just how this triggering works to morph a larva into a queen in waiting, but the repercussions of the histone code discovery could go far beyond this. Potentially, they could explain how pesticides in a bee’s diet change bee physiology and behavior: according to Dr. Paul Hurd, "Indirect dietary-mediated effects are also of particular relevance to insect pollinators. Prime examples are from systemic pesticides used on agricultural crops, which accumulate inside nectar and pollen and therefore enter honey bee diet, in some cases with detrimental effect. By studying the impact of diet and particular chemicals on the histone code during honey bee development and behaviour, we may be able to identify how certain pesticides contribute to the decline of some colonies." This, in turn, could help us understand the interactions between genes that lead to bee diseases, including, potentially, the CCD phenomenon.
To read more, visit: http://phys.org/news/2012-12-components-epigenetic-code-honey-bee.html#jCp
“Honey-bees found to have bite that stuns,” BBC News, Oct. 26: Biologists in Greece have discovered that honey bees actually bite pests like Varroa mites and wax moths, which are too small for bees to sting. When bees bite, they secrete a chemical called 2-heptanone which stuns these pests, giving the bees a window of opportunity to kick the mites or moths out of the hive. 2-heptanone is now being studied for possible use as a local anaesthetic for human beings. For more information, click here. Complete URL: http://www.bbc.co.uk/news/technology-20080389. To read the complete research study, "The Bite of the Honeybee: 2-Heptanone Secreted from Honeybee Mandibles during a Bite Acts as a Local Anaesthetic in Insects and Mammals," click here.
Hygenic Bee Breeding on the Olympic Peninsula
This February 2012 article from Onearth Magazine profiles Dan Harvey and his work breeding disease-resistant bees at the Olympic Wilderness Apiary. Very interesting overview of the challenges of breeding bees to meet disease and environmental challenges. Complete URL: http://www.onearth.org/article/the-green-beret-beekeeper