Plight of the bumblebee: Nature Newsin a bid to curb the rapid decline in 10%of wild North american bumblebee species,
international researchers have agreed on the key scientific priorities that will drive the next steps including the establishment of a body to push forward research.
The United states and Canada are home to about 50 species of native bumblebees (Genus bombus), which are important wild pollinators of fruit and vegetable crops.
Several species have been domesticated and used for commercial pollination in tomato greenhouses. Honeybees tend to perform poorly in tomato pollination.
But in the last three years, researchers have identified five North american species that have undergone a relatively swift population reduction since the 1990s
For example, the Bombus franklini worker bee was widespread in northern California and southern Oregon in 1998,
government agencies and commercial breeders to set future research priorities that might help to stem declines in bumblebee numbers.
such as finding the cause of the bumblebee disease thought to be behind the population crashes.
Some researchers have pinned the die off of native bumblebees on a fungal pathogen, Nosema bombi, which could have been introduced into the United states
when commercial bumblebees introduced into Europe by breeders then brought back escaped into the wild.
A related parasite has been implicated in the well-known decline of honeybees, although the two events seem to be unconnected,
and identify any other diseases possibly infecting the bumblebees. Other attendees concentrated on climate-change impacts that could be exacerbating the decline.
which may mean queen bumblebees find less nectar when they come out of hibernation. This group proposed long-term monitoring projects
In order to check the status of bumblebee populations across the United states conference participants suggested gathering and digitizing information from databases of different agencies,
Scientists at the conference also identified a need for basic research into bumblebee genetic diversity.
Attendees also agreed on a proposal to create an IUCN bumblebee specialist group that can coordinate the necessary research that will help policy-makers counteract the population loss.
many are hopeful that work from the conference will start to stem the bumblebee's decline.
Dengue control The release of male mosquitoes genetically engineered to be sterile can control dengue fever by suppressing the population of the insects that carry the disease, scientists at Oxitec,
They were reporting the results of a field trial of transgenic Aedes aegypti mosquitoes in a town on Grand Cayman
Malaysia will begin field trials of the mosquitoes in the next few months. See go. nature. com/6rxdjp for more.
Sterile moths wipe out cotton pest: Nature Newsbetween May and October for four consecutive years, aeroplanes crisscrossed the morning skies above Arizona's cotton fields, dropping millions of tiny moths onto the croplands below.
The little grey insects are among the world's most notorious agricultural pests: their larvae are the pink bollworms (Pectinophora gossypiella), also known as'pinkies'.
'However, the moths released from the planes were different from those responsible for the caterpillars munching their way through the state's cotton crops.
They were sterile. The moth-drops were part of a programme to wipe the dreaded pinkie off the Arizona map for good.
State officials hoped that the combination of sterile moths and genetically modified cotton crops, engineered to produce a toxin deadly to pinkies,
would put an end to farmers'costly struggle against the caterpillars. The strategy was intended to restrict the spread of toxin-resistant pink bollworms by flooding the population with sterile moths.
When rare resistant moths emerged as they inevitably would, they would probably encounter a sterile partner,
and their genes would be erased from the population. It was a risky approach. To test the plan,
Arizona farmers had to give up the strategies normally used to suppress toxin-resistant bollworms so
if the sterile-moth strategy failed they could be faced with a bigger pinkie problem than ever.
When Bruce Tabashnik, an entomologist at the University of Arizona in Tucson, first heard about the scheme, he was worried.
My gut feeling was that this wouldn't work, he says. But as Tabashnik and his colleagues report today in Nature Biotechnology1
%The pink bollworm was gone all but. Sterile insect releases have already been used to drive down populations of the Mediterranean fruit fly,
or Medfly, in Guatemala, Mexico and the United states; screw-worms in the United states, Central america and Libya;
and tsetse flies on the island of Zanzibar, off the coast of Africa. The technique works best on pests that are not particularly populous.
If you have something like aphids or thrips, where there are thousands on a plant, it's kind of hard to release enough sterile insects to do any good,
says Fred Gould, an entomologist at North carolina State university in Raleigh, who wasn't involved in the study.
But where pinkies were concerned, genetically modified cotton crops had driven already down the population one million-fold,
The idea behind the refuges is to keep a population of non-resistant moths close at hand as potential mates for any resistant moths that arise.
Unfortunately, however, refuges also guarantee a steady local population of pink bollworms. After a while, farmers came to resent the refuges that allowed the bollworm to persist year after year,
costing them millions of dollars annually in crop losses and insecticide sprays. They asked the US Environmental protection agency for permission to dispense with the refuges
and instead begin releasing sterile moths. Still sceptical Tabashnik and his colleagues developed computer simulations to predict the consequences of the farmers'proposed strategy.
and sterile-moth releases could wipe out pest populations and stave off Bt resistance for at least 20 years.
In 2005, the Pink bollworm Rearing Facility in Phoenix began cranking out pinkies for the Arizona experiment.
The factory treated the moths with just enough radiation to damage the chromosomes in their reproductive cells without causing injuries that would prevent their survival in the wild.
about 2 billion pink bollworm moths were released into Arizona's cotton fields. By 2009, a survey of 16,600 cotton bolls from conventional crops yielded only two pink bollworm larvae,
and farmers had stopped using insecticide sprays to keep the pinkie population in check. So far, no live pink bollworm caterpillars have been found in bolls of cotton this season,
says Tabashnik. The results are tremendous says entomologist William Hutchison at the University of Minnesota in St paul,
Unfortunately sterile-insect release plans require extensive resources, Hutchison cautions. Plans to eliminate the pink bollworm from the United states and northern Mexico cost $30 million a year between 2006 and 2009.
In Arizona, says Tabashnik, it's conceivable that farmers will someday no longer have a use for Bt cotton at all.
whether pink bollworm is eradicated or not, it's a question of how economically damaging it is,
And in 2009 and 2010, pink bollworm was no longer an economically damaging pest in Arizona.
Mayans converted wetlands to farmland: Nature Newsthe ancient Maya civilization is recognized widely for its awe-inspiring pyramids, sophisticated mathematics and advanced written language.
and it seems that honeybees are no different. Sleep-deprived bees are less proficient than their well-rested hive mates at indicating the location of a food source to other members of the colony by waggle dancing the figure-of-eight dance used to communicate the quality
and location of nectar supplies to the hive according to a study published online this week in the Proceedings of the National Academy of Sciences1.
Like all animals, European honeybees (Apis mellifera) rely on a sleep-like state of inactivity to survive
but sleep in insects and the effects of sleep deprivation on their behaviour are understood poorly. Barrett Klein who led the study as a graduate student at the University of Texas at Austin,
says that sleep deprivation could conceivably affect bees when hives are invaded by predators or parasites,
when apiculturists transport colonies over long distances, or as an everyday consequence of the busy nature of hives.
Bees bustle around, frequently bumping into each other, he says. It's also possible that sleep deprivation could exacerbate colony collapse disorder,
Klein and his colleagues devised a method to keep some bees within a colony awake without disturbing the rest of the hive.
They attached magnetic steel discs to 25 bees that had been trained to visit a feeder of sucrose solution located 1 kilometre away from the hive.
was passed back and forth along one wall of the hive for 12 hours, jostling the steel-tagged bees
and their well-rested copper-tagged hive mates for 48 hours, watching a total of 545 waggle dances.
The team found that steel-tagged bees were less able than those with copper tags to indicate the direction from the hive to the feeder (see videos of waggle dances performed by non-sleep deprived
The 2. 5-metre, mid-infrared telescope is mounted on the back of a Boeing 747 that flies in the stratosphere above much of the atmospheric water vapour that absorbs infrared light.
or a moth's almost perfect mimicry of tree bark. In some snails, however, it's simply down to a poor fit with a snake's jaw.
and will begin to do the same for insects in February. Logging is due to start in the second half of the year, after
such as fungus-farming ants although compared to the ants, which actively feed, nurture and defend their crops,
and insects, would make the wood produced there the most environmentally preferable in the world,
Take the endangered Quino checkerspot butterfly Euphydryas editha quino of Southern California. We do know that climate change is important:
and warm the butterfly's habitat it will cause increased starvation and extinction. But many populations are affected also by an invasive geranium from the Mediterranean
which is out-competing the butterfly's host plant. This is further aided by air pollution from Los angeles and San diego,
placed in areas the butterflies can colonize as climate shifts. So how is climate change affecting Earth's flora and fauna?
Almost two-thirds of species, including many birds, frogs, butterflies, trees and grassland flowers, breed or bloom earlier.
But we cannot be sure that global warming is the reason a local butterfly or wild flower species is becoming extinct or expanding northwards?
Likewise, many terrestrial plants and insects are moving or expanding pole-wards. Are these not clear fingerprints of climate change?
If you have data over a large area like our butterfly study of all of Europe3 then you can definitely say the northward shifts of two-thirds of European butterflies in the UK, France, Sweden,
NASA's other two shuttles are each due to fly once more this year before the agency's shuttle fleet retires.
Size doesn't always matter for peacocks: Nature Newsthe sight of a feather in a peacock's tail, Charles darwin wrote in 1860,
makes me sick. The seemingly useless, even cumbersome, gaudy plumage did not fit with his theory of natural selection, in
But Darwin eventually made peace with the peacock's train, and its plumage has become the poster child for his theory of sexual selection, in
Research in which peacocks'tails were plucked experimentally, published online this month in Animal Behaviour1, now suggests that the answer is yes but only sometimes.
Dakin and a colleague, Robert Montgomerie, tracked three populations of feral peacocks and peahens during the spring breeding season,
Beginning in the 1980s, Marion Petrie, a behavioural ecologist at Newcastle University, UK, examined the role of the peacock's tail in mating rituals.
I started to work on peacocks because Darwin had suggested it, and nobody had gone out and tested the idea,
I think there's clear evidence that peahens use a peacock's tail in their mate choice,
We propose that the peacock's train is an obsolete signal for which female preference has already been lost
Dakin repeated Petrie's experimental work by plucking the feathers of peacocks. She noticed a drop in their success with peahens.
and peacocks that manage to hold onto their plumes are likely to be the healthiest and fittest.
Nature Newsfor Scott Cornman, the honeybee genome is prized a resource, yet he spends much of his time removing it.
Cornman, a geneticist for the Bee Research Laboratory of the US Department of agriculture (USDA) in Beltsville, Maryland, is trying to characterize the various pathogens that plague the honeybee (Apis mellifera), arguably the world's most important insect.
His strategy is to subtract the honeybee genome from every other stray bit of genetic residue he can find in bee colonies, healthy and diseased.
soon after the honeybee genome was sequenced (Honeybee Genome Sequencing Consortium Nature 443,931-949; 2006), and for many it was a chance to marvel at a field transformed.
There has been made a lot of progress on how disease affects honeybees at the molecular level, says Christina Grozinger, director of Pennsylvania State university's Center for Pollinator Research in University Park, one of the conference organizers.
Around the same time that the genome was published first, honey  bee colonies across much of the Northern hemisphere began to show alarming declines.
A syndrome dubbed colony collapse disorder (CCD) has been causing the insects to die off in large numbers,
leaving well-provisioned hives suddenly empty. Meanwhile other parasites, such as the Varroa mite (Varroa destructor),
as well as potential strategies for protecting the insects from a multitude of threats. At the meeting, Cornman presented data showing that hives affected by CCD have higher levels of microscopic gut fungi called Nosema,
and a greater prevalence of several viruses, two of which had not been detected in bees before. Yet despite having a multitude of enemies
In some insects, double stranded-rna RNA, a hallmark of viral infection, can provoke a specific antiviral immune response.
At the meeting, Michelle Flenniken, a virologist at the University of California, San francisco, presented evidence that, in honeybees, it can also trigger a general immune response that might ward off a variety of threats.
This may be a new viral response that hasn't been characterized well in honeybees, says Flenniken,
The grasshoppers have infested already Saudi arabia's Red sea coast. Special locust squads, guided by satellite data to the breeding grounds,
But international agricultural officials worry that some of the grasshoppers might escape to Yemen, where they often breed.
which carried multiple genes for insect and herbicide resistance, were stable in the field. I would expect that by the end of the decade,
making the plant produce toxins that confer resistance to some insect pests. A Bt cotton variety is being developed for Kenyan farmers at KARI.
Mosquitoes score in chemical war: Nature Newskey weapons in the fight against malaria, pyrethroid insecticides, are losing their edge.
But they have created also intense selection pressure for mosquitoes to develop resistance. Data are coming in thick and fast indicating increasing levels of resistance,
Malaria-control programmes often lack insect-resistance monitoring, and detection of all forms of resistance is not easy.
Quick, cheap tests can pick out gene mutations that help the mosquitoes'nerve cells withstand pyrethroid attack. But other forms of resistance,
which depend on increased levels of mosquito enzymes that can destroy pyrethroids before they reach their target,
so that mosquitoes resistant to one would be killed by the other. In areas where pyrethroid bed nets are used,
Research targeting mosquito control is compared grossly underfunded with that on malaria drugs and vaccines she adds,
which in many regions function as important fruit pollinators. Andrew Cunningham, a wildlife epidemiologist at the Institute of Zoology in London,
says Andrew Dobson, an infectious-disease ecologist at Princeton university in New jersey who commends the project's focus.
which, like humans, flies and sea anemones, have biradial or bilateral symmetry their body plan can be sliced into only two identical pieces.
and reduce the amount of weeds and harmful pests such as the rice planthopper. This invasive insect has the potential to devastate entire rice fields an outbreak in Thailand last year destroyed four per cent of the country's harvest.
By regulating the amount of nitrogen in the ecosystem, the practice also minimised the need for applying fertiliser.
And insects attracted to the plants provided extra food for the fish. More from Scidev.
Asteroid fly-by Marshalling everything from major radar facilities to backyard telescopes, astronomers geared up this week for a fantastic view of an asteroid called 2005 YU55.
The third is the potential for global warming to expand the range of insect-borne diseases."
short DNA sequences that uniquely identify a species. Bar-coding makes it possible to distinguish between two species of butterfly, for example,
which genes get turned on and off in insects and fish, but this is the first study to look at nonhuman primates,
A key factor in this progress has been improved control of mosquitoes, which transmit the Plasmodium parasite a potent killer that claimed an estimated 655,000 lives in 2010 alone.
But health officials fear that the spread of insecticide-resistant mosquitoes could bring about a resurgence of the disease.
WHOTHE WHO report says that insecticide-resistant mosquitoes already inhabit 64 Â malaria-ridden countries (see map.
where mosquitoes are frequently resistant to compounds known as pyrethroids and even to the organochloride DDT, venerable tools of mosquito control.
Because they are extremely safe for children, effective against mosquitoes and affordable, pyrethroids are the only insecticides used to treat bed nets,
and other insecticides favours resistant mosquitoes.""In 2004, there were pockets of resistance in Africa, and now there are pockets of susceptibility,
Their spending on mosquito control is already high in 2009,39%of the Global Fund s malaria expenditures went towards insecticide-treated bed nets and household spraying,
It is also one of several companies partnering with the IVCC to create innovative mosquito-control products.
for instance, mosquitoes regained susceptibility to pyrethroids after five years of treatment with an organophosphate. But some African countries lack the surveillance needed to spur such an approach.
Preemptive treatment of children living in regions where the mosquito-transmitted disease is prevalent only during the rainy season could avert 11 million cases and 50,000 deaths a year.
His research has focused on the fundamental nature of the relationships between plants and insects and the development of tools for managing insect pests.
Two months into his new role Ramaswamy chatted with Nature about NIFA research, working with a tight budget,
around 94%of the soya beans and 88%of the maize (corn) grown in the United states is engineered genetically to resist herbicides, insect pests or both, according to the US Department of agriculture.
and insects have evolved resistance to the modified crops3. Seed companies can counter this by engineering new crops that are resistant to additional herbicides such as a new soya bean developed by Dow Agrosciences of Indianapolis,
Job swapping makes its mark on honeybee DNASUBTLE differences in the DNA of honeybees are reflected in the bees'roles within the hive.
All honeybees (Apis mellifera) are born equal, but this situation doesn t last long. Although genetically identical, the bees soon take on the specific roles of queen or worker.
These roles are defined not just by behavioural differences, but by physical ones. Underlying them are minor modifications to their DNA:
Once a bee is a queen or worker, they fulfil that role for life the change is irreversible.
which look after and feed the queen and larvae, and most then go on to become foragers,
which travel out from the hive in search of pollen. Again the two types have very different methylation patterns in their DNA.
and Gro Amdam of Arizona State university in Tempe, the researchers coaxed forager bees back into nursing roles by removing all the nurses from the hive
But Amdam says that the fact that honeybees can revert to a previous role indicates that there is a kind of epigenetic roadmap."
The development of new countermeasures, from diagnostics to antibiotics and antivirals to respirators, will help protect human lives in the face of new bugs and superbugs.
The teeth have provided enough information for palaeontologists to say that the animals ate insects and plants but have yielded little information on where the creatures lived.
show that low-level exposure to a combination of two pesticides is more harmful to bumblebee colonies than either pesticide on its own.
and stalks when insects drilled into the plant, creating a convenient landing pad of dying tissue for the fungus.
Fungus that controls zombie-ants has own fungal stalkeran article by Scientific American. An unsuspecting worker ant in Brazil's rainforest leaves its nest one morning.
But instead of following the well-worn treetop paths of its nest mates, this ant stumbles along clumsily,
Within days the stem of a fungus sprouts from the dead ant's head. After growing a stalk,
where they can be picked up by other passing ants. This strange cycle of undead life and death has been documented well
and the Camponotini carpenter ants that it infects. Fossil evidence implies that this zombifying infection might have been happening for at least 48 million years.
Recent research also suggests that different species of the fungus might specialize to infect different groups of ants across the globe.
And close examination of the infected ant corpses has revealed an even newer level of spooky savagery other fungi often parasitize the zombie-ant fungus parasite itself.
Deadly infection This clever Ophiocordyceps fungus depends on ants to reproduce and spread, but it has found an abundant host animal.
As Hughes notes, ants have been incredibly successful, currently comprising an estimated half of all insect biomass worldwide.
One of the first clues that a tropical carpenter ant has become infected with Ophiocordyceps is that it will leave the dry tree canopy
and descend to the humid forest floor, staggering over debris and plants. Infected ants behave as zombies,
Hughes and his colleagues wrote in a 2011 BMC Ecology paper describing some of the latest findings.
The ant will walk randomly, displaying convulsions that make them fall down and thus preclude them from returning to the canopy,
however, be blamed on the ant. While the manipulated individual may look like an ant, it represents a fungal genome expressing fungal behavior through the body of an ant,
the researchers noted in the paper. Hence the zombie designation. More from Scientific American. Evans suggests that a nerve toxin spurred on by the fungus is at least partly to blame
judging from the uncoordinated movements and hyperactivity of the ants infected, he says. Ants that have been dissected at this stage of infection reveal heads already full of fungal cells.
Eventually, an affected ant will stop on the underside of one leaf, roughly 25 centimeters from the forest floor,
and clamp down on the leaf's main vein. This position appears to be optimal for the fungus's later stage in
which it ejects spores onto the soil directly below.)Biting leaves is not normal ant behavior.
when the infected ant bites onto the leaf vein in it's so-called death grip this atrophy causes it to have lockjaw,
the ant would fall to the ground, destroying the launching point for the fungus's spores.
By that stage, cells from the fungus have grown even more numerous in the ant's body.
They have proliferated around the ant's brain and between surrounding muscle fibers but have not entered the brain,
Ants appear to die within six hours after their final bite. About two to three days later a fungal stalk will start to emerge from the back of the ant's head.
After maturing over the course of weeks the stalk's head will shoot spores onto the soil below.
Foraging worker ants can unwittingly pick up spores as they pass by. The death of an ant outside of its colony and subsequent growth of the fungal stalk might be key adaptations of the fungus,
Ants quickly remove dead nest mates so that dying in the nest would not allow sufficient time for stalk development
and spore release before the dead host ant was ejected, Hughes and his colleagues noted in their BMC Ecology paper.
The doomed ants do not wander too far afield, often ending up within meters of their familiar territory.
And large groups of dead ants are commonly found near colonies. These graveyards can contain anywhere from 50 to hundreds of corpses,
Ants'complex and large social groups are thought to be one of the keys to their global abundance.
The fungus has capitalized on ants'social behavior. Sociality can be thought of as evolution's winning lottery ticket
however, cannot live without the winning ants'continued success. It appears to be an obligate parasite,
local species of ant for it to inhabit, grow and propagate its spores. A specialized but global threat The ants best known for getting zombified by the Ophiocordyceps fungus are tree-dwelling carpenter ants found in Brazil and Thailand,
but the fungus is thought to be distributed broadly in tropical areas around the globe. In fact, the full range of strange behavior observed in Sulawesi
Although many ants in different areas are infected similarly and dispatched in this strange way, the species of fungus infecting them is not at all the same.
Each of these species was associated with a different Camponotus ant species, denoting a high degree of specialization.
Ancient scourge The zombifying fungus's vast geographic distribution also hints at the possibility that it has been possessing ants at least
Research published in Biology Letters in 2010 describes a 48-million-year-old fossilized leaf from Germany that bears the distinctive scars of a bite from an ant's mandible on its main vein.
which depends, in turn, on the carpenter ant colony. Once you're very successful, something else will take advantage of it,
The zombie-ant fungus's doom, of course, is little consolation for the infected ant. But the castration of the ant-killing fungus means that it will not go on to turn other local ants into zombies.
This hobble might, in fact, be one of the reasons the zombie-ant fungus has been so successful over the long term.
as long as there are ants nearby to infect. In addition to the fungicidal fungi scientists have seen also small bugs laying their eggs in the infected ant corpse,
where their larvae can then eat the growing fungus. These bugs include specialized gall midges (in the Cecidomyiidae family)
and a species that appears to be new to science, Hughes says. It seems their entire nutrition comes from eating the fungus that manipulates ant behavior.
Evans is collecting more zombie ants in Brazil, as part of what he and Hughes have dubbed unofficially the World Ant Tour.
When Evans returned to a field site in Ghana where he had found different genera of possessed ants in the 1970s
and the challenges farmers in tropical countries face from insects and fungi that infect their crops,
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