since the phenomenon was discovered in fruit flies 50 years ago. A new study a highlight in the March issue of the journal Genetics provides the latest plot twist.
When male flies make their sperm the SD gene (call it A) manages to rig meiosis--the specialized cell division that makes sex cells
Humans flies all of us have been attacked for millennia by selfish genetic elements that want to make as many copies as possible Reenan said.
Sometimes as in SD flies there are no apparent ill effects but when the selfish genes come in the form of viruses
Over 20 years Robertson recorded visits from 1429 pollinators (including flies beetles and butterflies as well as bees) to 456 plant species. He identified
These pollinators including bees flies butterflies and beetles usually live in natural or semi-natural habitats such as the edges of forests hedgerows or grasslands.
The researchers then put carpenter ants houseflies and German cockroaches to many of the same tests. Although they groom a bit differently than cockroaches--flies
and ants seem to rub their legs over their antennae to remove particulates with ants then ingesting the material off their legs--the tests showed that these insects also accumulated more cuticular hydrocarbons
#24 new species of flower fly have been found in Central and Southern Americaa team of scientists have described twenty four new species of dipterans belonging to Quichuana genus of which only a further 24 species were known.
The researchers including two Spanish biologists have been studying the forests of Central and Southern America for ten years and they have published now their results in the Zoological Journal of the Linnean Society.
A ten-year study in forests of the American continent has resulted in the description of 24 new insect species from the Quichuana genus that are also known as'flower flies'.
#West Nile virus spreading due to mosquitoes in orchards and vineyards, experts warnwashington State university researchers have linked orchards
and vineyards with a greater prevalence of West Nile virus in mosquitoes and the insects'ability to spread the virus to birds horses and people.
Is that because there are more mosquitoes there? That hasn't really been linked together. Crowder working with fellow entomologist Jeb Owen other WSU colleagues and the State department of Health merged data from a variety of sources including West Nile infections in humans horses
and birds surveys of virus-bearing mosquitoes breeding bird surveys and detailed land use maps and climate data from around the Northwest.
and birds also have significantly more mosquitoes--as well as American robins and house sparrows the two bird species implicated the most in the disease's transmission.
These same habitats are also resulting in much higher rates of infection within mosquitoes themselves said Crowder.
and American robins abundance of mosquitoes and the actual prevalence of West Nile in mosquitoes--are increasing in landscapes with a higher proportion of land in orchard habitats.
It's still unclear why the habitats would create such a perfect storm for the virus. The researchers speculate that mosquitoes are drawn to orchards for plant nectar during flowering
and Great depression-era ditches constructed by Works Progress Administration (WPA) in an effort to control mosquitoes.
but squattier Spartina patens) and other high marsh plants dominate The old WPA mosquito ditches also fulfill the crabs'habitat requirements.
Mosquito ditches that can only be reached by a hard slog through undeveloped marshland do not display the striking die off
The revelation of the slumbering menace of the mosquito ditches raises the prospect of other submerged impacts that may surface under the influence of new contemporary pressures.
As land use shifted from agriculture toward tourism the local chamber of commerce funded an effort to draw off standing water through drainage ditches to suppress the mosquito population.
The program was probably not very effective at controlling mosquito-borne disease Coverdale says but it did put a lot of people to work
The Cape cod Mosquito Control Project continues ditch-dredging under the Barnstable County Department of health and the Environment.
The parasite is transmitted through the bite of the tsetse fly a large flying insect found throughout the midcontinent of Africa that survives by drinking blood from human and animal hosts.
or eradicating the tsetse fly which has proven difficult. Even when humans are successful in avoiding the bite of the tsetse fly domesticated animals like cattle
and pigs may fall victim to nagana the animal version of sleeping sickness which when translated from Zulu means depressed in spirit.
By conducting this epidemiological study on a commercial dairy farm in Northern California we were able to demonstrate that the virus overwinters in female midges that had fed on an infected animal during the previous season said lead author Christie Mayo a veterinarian
About bluetonguebluetongue disease first identified during the 1800s in southern Africa is transmitted by the Culicoides biting midge a tiny gnat sometimes referred to as a no-seeum.
when midges are abundant in late summer and fall but there has been speculation over how the virus survives through the winter.
and the biting-midge populations plummet transmission appears to cease for more than six months but the virus reappears
when temperatures warm the following season Findings from California dairythe researchers monitored cows and midges on a Northern California dairy farm for more than a year.
They documented for the first time the presence of genetic material for the bluetongue virus in female midges that were collected during two consecutive winter seasons.
The bluetongue virus was widespread in both the dairy cows and the midges from August to November.
Surprisingly however the researchers discovered that the virus was also present in female midges captured in February of both 2013 and 2014.
The researchers concluded that those long-lived female midges had been infected with the bluetongue virus during the previous warm-weather season.
#Mosquito fact and fictionone of Jason Pitts'favorite stories is about mosquitoes and their strange attraction to Limburger cheese.
and other mosquito-borne illnesses by developing new and improved attractants and repellants. In his spare time he collects interesting facts
In the 1990's Dutch biologists put Limburger cheese in a wind tunnel with malaria mosquitoes and were surprised to find that females were drawn to the smell he said.
and that is what attracted the mosquitoes. The researchers used this discovery to develop Limburger-based traps that mosquitoes find two to three times more attractive than humans.
Pitts has found that the story about the mosquitoes and Limburger is a real crowd pleaser.
He has discovered also that two topics almost always come up when people learn that he studies mosquitoes for a living.
People want to know more about the giant mosquitoes in their homes and they wonder why mosquitoes appear to bite some individuals more than others.
Times past counting people have told Pitts that they have giant mosquitoes at home and asked him
if they are the biggest mosquitoes in the world. He responds by asking just how big these giant mosquitoes are.
If the answer is two inches or more Pitts informs them that they aren't mosquitoes at all:
They are called crane flies also mosquito hawks. Crane flies are harmless. They don't bite and they don't eat mosquitoes as some people claim he tells them.
Pitts is certain of his ground because the world's largest mosquitoes have a wingspan of only an inch
and they are found right here in Tennessee. I've caught them in my backyard
but they are very hard to find. You really have to hunt for them Pitts said.
They are called elephant mosquitoes and they don't feed on blood. In fact their larvae feed on other mosquito larvae
so they can potentially help reduce the population size of other harmful mosquitoes. There are more than 3000 species of mosquitoes worldwide
but only 150 of them are found in North america Pitts said. We only know of around 40 species in Tennessee he reported.
The second question Pitts frequently gets is Why am I the one that mosquitoes always bite?
We have a general answer to that question: It has to do with individual variations in body odor
but right now we don't understand the specific combination of odorants that mosquitoes find most attractive Pitts said.
Also different species are attracted to different smells. The source of the aromatic compounds that produce body odor are bacterial colonies that exist on human skin particularly in dark moist areas such as the arm pits and between the toes.
Pitts and his colleagues have discovered that mosquito antennae are filled with hundreds of tiny odor receptors
which are tuned individually to detect specific odors. While they have identified dozens of aromatic compounds that trigger the mosquito's antennae the researchers haven't discovered one that acts as a super-attractant.
The experimental evidence strongly supports the conclusion that mosquitoes are attracted by blends of odors rather than a single odorant he explained.
Individual compounds on the other hand can act as powerful repellants. Natural repellants such as clove oil citronella lemon grass eucalyptus castor oil peppermint lavender and cedar oil all work to a limited extent Pitts said
but almost all of them are less effective than the synthetic repellant DEET and they need to be reapplied more frequently.
Actually odors combined with heat are the basis of the mosquitoes'short-range detection system Pitts said.
The mosquitoes do so in part by sensing the carbon dioxide in human breath. When we exhale our breath contains four to five percent more carbon dioxide than the surrounding air
and mosquitos can detect this difference. As you exhale your breath is carried by air currents as a series of bubbles enriched in CO2 that can persist for some time Pitts said.
Female mosquito flight is activated by CO2 and she can dart upwind from bubble to bubble in pursuit of her target.
According to some studies mosquitoes are attracted more strongly to human breath after a person has downed a beer
Some people claim that mosquitoes can fly between raindrops. This may seem farfetched but actually has an element of truth.
A study using high-speed video has shown that mosquitoes don't exactly fly between drops so much as the raindrops bounce off them.
Surprisingly the mosquitoes'small size and flexible exoskeleton actually reduces the impact of the raindrops on the insects'bodies.
Many experts categorize mosquitoes as specialists. That is different species of mosquitoes prey on specific animal hosts.
For example the malaria mosquito Anopheles gambiae prefers to feed on humans while other species may prefer birds dogs sheep etc.
However Pitts argues that these insects are opportunists rather than true specialists. For example numerous studies of A. gambiae taken from African huts have found that virtually all the females collected contained human blood:
This strongly suggests that Anopheles females are not specialists that require human blood but instead are opportunists--they may have preferences
Despite all the time and effort that researchers have spent studying mosquitoes there still is a tremendous amount that they don't understand Pitts said.
Mosquitoes have managed to survive for more than 46 million years--more than 100 times longer than man
Each year 700 million people worldwide suffer from mosquito-borne diseases and millions die. Story Source:
The MODIS or Moderate Resolution Imaging Spectroradiometer is an instrument that flies aboard NASA's Terra and Aqua satellites.
For example the crop wild relative of the wheat crop Aegilops tauschii is resistant to Hessian fly
and eventually evolving the ability to glide and fly. He has documented many ways that animals in the wild from lizards
whether oestrus could be stimulated while sows were still feeding their piglets so the sows could be mated before their piglets were weaned.
The research showed that providing sows daily contact with a mature male pig seven days after giving birth is sufficient to stimulate oestrus regardless of
#Genetically engineered fruit flies could save cropsreleasing genetically engineered fruit flies into the wild could prove to be a cheap effective and environmentally friendly way of pest control according to scientists at the University of East Anglia andâ Oxitecâ Ltd.
New research published today reveals how the release of genetically engineered male flies could be used as an effective population suppression method â#saving crops around the world.
The Mediterranean fruit fly is a serious agricultural pest which causes extensive damage to crops. It is controlled currently by a combination of insecticides baited traps biological control
and studied the impact of releasing Oxitec flies. Lead researcher Dr Philip Leftwich from UEAÂ##s school of Biological sciences and Oxitec said:
â#oethe Mediterranean fruit fly infests more than 300 types of cultivated and wild fruits vegetables and nuts.
and causes extreme damage to crops all around the world. â#oeof all of the current techniques used to control these flies SIT is considered the most environmentally friendly as it uses sterile males to interrupt matings between wild males and females.
because the irradiation method used for sterilisation weakens them. â#oeour research looked at whether releasing Oxitec flies
so that only male fly offspring survive could provide a better alternative. â#oethe genetically engineered flies are not sterile
and we have shown they are healthier than the flies traditionally used for SIT. â#oewe simulated a wild environment within secure eight-meter greenhouses containing lemon trees at the University of Crete.
When we tested the release of the genetically modified male flies we found that they were capable of producing rapid population collapse in our closed system. â#oethis method presents a cheap and effective alternative to irradiation.
Similar to a plane honeybees require clean fuel in order to fly. Both fipronil and imidacloprid negatively affected the mitochondrial bioenergetics of the head and thorax of the honeybees.
Their study of fruit flies and honey bees shows a direct causal link between brain metabolism (how the brain generates the energy it needs to function) and aggression.
In separate experiments postdoctoral researcher Hongmei Li-Byarlay and undergraduate student Jonathan Massey found that reduced oxidative phosphorylation in fruit flies also increased aggression.
Because fruit flies and honey bees are separated by 300 million years of evolution this is a very robust and well-conserved mechanism he said.
which folds under the body when the bee flies. Perched at the mouth of a flower the bee unfolds the beaky maxilla
They are docked usually tail without analgesia as a preventative measure to reduce the chances of flies laying eggs on dirty tails
#Dairy farmers keep flies guessing by alternating pesticidesold-fashioned fly swatters may be the most foolproof housefly killer
Flies spread disease and a host of pathogens that cost farms hundreds of millions of dollars in annual losses.
Unfortunately with the repeated use of the same insecticides flies develop resistance through genetic mutations that make these products less effective.
Cornell entomologist Jeff Scott and colleagues analyzed levels of resistance to six insecticides in flies and they have identified the mutations that led to resistance in houseflies and from cattle farms in nine states around the country.
and one mutation lets a fly survive then that mutation is carried forward in the population.
and Physiology and are working to understand three main mutations that confer pesticide resistance in houseflies.
We think it is due to fitness costs where a mutation allows the fly to survive insecticides
Mosquitoes and ticks are the two pests you primarily want to avoid because they potentially carry infectious diseases says Jennifer Layden MD infectious disease specialist at Loyola University Health System.
and Rocky mountain spotted fever and mosquitoes can spread West Nile Virus. Insect repellents are used to avoid exposure to pests that can bite attach
and cattle and is spread by biting midges. In sheep the bluetongue virus can cause abortion congenital abnormalities
If the disease reproduction number for the cattle-midge-bluetongue system with or without sheep is greater than one bluetongue persists in cattle
and midges even though it may eradicate the sheep relying on cattle as a reservoir. In the second situation where the reproduction number of all host and vector species coexisting is greater than one
while the reproduction number for the cattle-midge-bluetongue system (without sheep) is less than one bluetongue
because it cannot persist on midges and cattle alone. The authors use different approaches of dynamical systems persistence theory to analyze the two situations.
and New zealand--by making female flies dependent upon a common antibiotic to survive. Dr. Max Scott professor of entomology at NC State and his research team genetically modified lines of female Australian sheep blowflies (Lucilia cuprina) so that they required doses of tetracycline in order to live.
Female blowflies that did not receive the antibiotic died in the late larval or pupal stages before reaching adulthood.
Several genetically modified lines lacking tetracycline showed 100 percent female deaths. Scott says that the gene construct responsible for lethality in antibiotic-free diets is female-specific Interestingly
This is essential for a male-only genetic control program to reduce blowfly populations Scott says as fertile males would pass the lethality construct on to female offspring
In the study the researchers showed that the tetracycline gene construct also works in Drosophila the fruit fly lab rat of the insect world that is a distant cousin of the sheep blowfly.
and Old world screwworm two major livestock pests that are close relatives of the sheep blowfly.
and Central america by releasing sterilized male and female flies Scott says. However a male-only strain offers several advantages including potentially more efficient population suppression for the ongoing program.
In addition by guarding their existing crops during the night farmers are exposed increasingly to malaria carried by mosquitos and soil-based worms
#Mosquito control pesticide use in coastal areas poses low risk to juvenile oysters, hard clamsfour of the most common mosquito pesticides used along the east and Gulf coasts show little risk to juvenile hard clams and oysters according to a NOAA study.
However the study published in the on-line journal Archives of Environmental Contamination and Toxicology also determined that lower oxygen levels in the water known as hypoxia
and environmental resource agencies as they manage the use of mosquito control pesticides near their coastal ecosystems.
This is compounded by a lack of data on the toxicity of mosquito insecticides for these shellfish.
and food sources for other estuarine species. Approximately 200 mosquito species live in the United states . In addition to causing painful itchy bumps to people mosquito bites can transmit serious diseases such as malaria dengue fever
and West Nile virus. One approach to controlling mosquitoes is to apply pesticides by spraying from planes or trucks over a large area.
However to effectively control mosquitoes the pesticides must target species which live in aquatic habitats that are also home to sensitive estuarine species This may pose a risk to coastal environments.
The study sought to address a lack of toxicity data for mosquito control pesticide effects on shellfish early life stages.
The research team examined the toxicity of four mosquito control pesticides (naled resmethrin permethrin and methoprene) to larval and juvenile life stages of hard clams (Mercenaria mercenaria) and Eastern oysters (Crassostrea virginica.
Overall clams were more susceptible to mosquito control pesticides than oysters. Naled an organophosphate chemical was the most toxic compound in oyster larvae
which compared the toxicity thresholds to concentrations expected in the environment the researchers calculated a low-level of risk to clams and oysters from application of these pesticides for mosquito control.
and launch a couple drones that fly out over his farms and collect imagery that's sent wirelessly to his office Bowman said.
Brazil for example has dengue fever--a viral infection that is transmitted to humans by Aedes mosquitoes which can cause life-threatening illness.
and misconceptions about how to repel mosquitoes and other biting insects which can leave people at risk of harm to their health.
Jumping plant lice that fly towards the source of the odor are duped: they will not find enough food there as the bacterium has lowered drastically the nutritional quality of infected leaves.
It may give flies wasps and other predators greater opportunities to attack undefended eggs and larvae.
and illnesses transmitted by food water and disease carriers such as mosquitoes and ticks. Some of these health impacts are already underway in the United states. Climate change will absent other changes amplify some of the existing health threats the Nation now faces.
Clayton says the parasitic nest fly may have invaded Ecuador's Galapagos islands via ships and boats from the mainland at an unknown time and showed up in large numbers in the 1990s.
So the birds have no history with these flies which is why they are sitting ducks.
From the perspective of the birds these things are from Mars. Knutie says the flies now infest all land birds there including most of the 14 species of Darwin's finches two
Nest flies have been implicated in population declines of Darwin's finches including the two endangered species. Clayton says the pesticide--permethrin--is safe for the birds:
whether the flies will evolve resistance as human head lice have done. Clayton believes that will not happen
Hawaiian honeycreepers infested with feather lice birds in Puerto rico afflicted by Philornis flies and the endangered Florida scrub jay parasitized by fleas.
Parasitic nest flies lay their eggs in finch nests which have shaped dome roofs of woven plant fibers.
After birds in a given nest finished breeding (within three weeks) and left the nest the scientists collected the nest dissected it counted the number of parasitic fly maggots
De la Rosa is a specialist in the biology of non-biting midges and a natural historian with his eyes always open to new discoveries.
#Insects represent link for antibiotic resistance traitsthose pesky house flies buzzing around your home or invading your springtime picnic could be doing more harm to human health than you realize.
There are a number of insects that are associated commonly with animals such as house flies and cockroaches said Ludek Zurek K-State professor of microbial ecology
House flies are common where animal manure is produced including in cattle poultry and swine operations.
Zurek and his colleagues collected house flies and cockroaches from food animal production locations including swine
and again we found house flies with multi-drug resistant bacteria. The house flies collected from the wastewater treatment plants likewise carried the same bacteria found in the waste itself he said.
House flies collected several miles from the wastewater treatment plants in surrounding urban areas had a lower prevalence of the antibiotic-resistant bacteria than those examined from the facilities themselves
but the bacteria still existed in those urban house flies. The study led the researchers to conclude that insects primarily house flies can pick up antibiotic-resistant bacteria
and disseminate them to surrounding areas. How serious that link is still needs to be investigated
Cockroaches and house flies are highly mobile and they are attracted to residential areas he said. They are attracted to our food and drinks.
The resistant strains multiply in the fly and can be left behind on food by fly regurgitation or spitting and defecation.
House flies aren't just a nuisance. They can carry antibiotic resistant bacteria so they should be taken seriously as a vector.
Olsen studies rice and cassava and is interested currently in rice mimics weeds that look enough like rice that they fly under the radar even
West Nile virus is spread by infected mosquitoes and targets the central nervous system. It can be a serious life-altering
#Secret of multiple insecticide resistance in mosquitoesresearchers at LSTM have discovered how unprecedented multiple and extreme-level resistance is generated in mosquitoes found in the rice fields of Tiassalã in southern CÃ'te d'Ivoire.
The paper CYP6 P450 enzymes and ACE-1 duplication produce extreme and multiple insecticide resistance in the malaria mosquito Anopheles gambiae published in PLOS Genetics today highlights the combination of stringently-replicated whole genome transcription
when the Anopheles gambiae larvae sampled from the rice paddies of Tiassalã were raised to adults and tested using WHO tube bioassays.
They proved to be resistant to all four of the insecticide classes available for mosquito control (Edi et al.
This is the first wild Anopheles population to display such complete multiple resistance which is a serious concern
In addition to many of the mosquitoes surviving a standard one-hour insecticide exposure (used as THE WHO standard to monitor the prevalence of resistance) the levels of resistance displayed in Tiassalã were very high with 50%of mosquitoes tested surviving for longer
The new work reveals that two members of the P450 gene superfamily in particular are expressed highly in resistant Tiassalã mosquitoes:
When these genes were transplanted into Drosophila resistance to pyrethroids and carbamates was generated in otherwise susceptible fly strains..
These genes are familiar candidates to LSTM researchers who have documented previously their links with pyrethroid and DDT resistance.
whereas carbamates and organophosphates target the neurotransmitter Acetylcholinesterase encoded by the gene ACE-1. This is where Tiassalã mosquitoes yielded another surprise contributing to their exceptionally high carbamate resistance.
This combination of distinct mechanisms provides the Anopheles population of Tiassalã with high levels of resistance and resistance across insecticides.
which mosquitoes can become resistant to the available arsenal of insecticides. Controlling populations like Tiassalã will be particularly challenging
which often are larger and stronger than the spiders themselves fly just above the tops of scrub vegetation said Mark Deyrup senior research biologist for the Archbold Biological Station who co-authored the study.
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