For example fragmentation reduces the availability of interior forest habitat that is preferred by many bird species. There are also a number of large predators such as big cats like the tiger
and modeling it in the U s. To better understand UAH graduate student Zirnstein's work you first need to think of Voyager 1 as more like a mole than a hawk best at sensing only its immediate surroundings.
It's the IBEX satellite that's the hawk mapping the whole of space from its Earth orbit based on energetic neutral particles that stream in to it from outer space.
#Pesticide regulation in California is flawedapproximately 30 million pounds of fumigant pesticides are used each year on soil that yields valuable California crops--strawberries tomatoes peppers and the like--in an attempt to control pests.
when a genetically modified trait passes from a crop plant to a closely related weed the weed gains the crop s engineered benefit#resistance to pests for example#only in the presence of the offending insects.
either selectively neutral in wild plants or if they have a benefit it depends on environmental factors like insects diseases
In 2002 she led a study that was the first to show that a gene artificially inserted into crop plants to fend off pests could migrate to weeds in a natural environment
When wood is injured such as by an insect or is being dried like we do dried with kiln lumber the torus
#African caterpillars resistant to GM maizelike many other transgenic crops Bt maize synthesises its own pesticide:
which kills pests in a matter of days. Perfect#Except when insect populations develop resistance to the toxin!
To date management strategies implemented to delay the evolution of resistance have been successful. Notwithstanding the success of these strategies IRD scientists and their South african partners have revealed now that a major pest of maize the moth Busseola fusca has developed an unusual defense mechanism against Bt toxin in South africa.
By contrast with the usual expectations this resistance is inherited as a dominant trait a characteristic that may have contributed to its rapid geographical expansion.
This result recently published in the journal PLOS ONE suggests that insect resistance management should be tuned more finely to local pests
and should go beyond the simple implementation of refuges for Bt-susceptible moths. Bt maize and resistance developmentgenetically engineered maize is created by introducing a gene into the plant genome that expresses a toxic protein from a bacterium i e.
which destroys the gut of any moth larvae eating the plant. The technique is effective and unlike wide spectrum pesticides it only targets larvae of moths.
However sooner or later insect species may be able to develop a mechanism of resistance against any pesticides.
Bt maize is not fundamentally different in this regard and in order to delay the evolution of resistance in pest populations the concept of maintaining refuges for Bt susceptible moths was developed.
Non-Bt maize fields are protecting Bt maize fieldsthe refuge strategy consists of planting a small proportion of land with non-Bt maize;
the aim being to maintain pockets of insects that remain susceptible to the toxin. In line with other known cases of Bt-resistance resistance in Busseola fusca was expected to involve modification of the cells in the gut wall
Since the probability of resistant individuals arising in the field is low any resistant insects surviving on Bt maize will mate with one of the many Bt-susceptible individuals originating from the refuge area
since 1995 with resistance yet to develop among lepidopteran pests. The exception to the rulehowever about seven years after Bt maize was introduced to South africa in the late 1990's scientists observed resistant Busseola fusca caterpillars
and more importantly these resistant insects seemed to reproduce and spread rapidly. To explain this phenomenon scientists in South africa together with IRD researchers crossed resistant South african moths with susceptible moths imported from Kenya where Bt maize is commercialized not yet.
The offspring developed perfectly on Bt maize and were as resistant as the South african resistant parents.
Unlike everything known so far this resistance evolved in the field was inherited as a dominant trait.
The moth does not seem to have followed the expected pattern of adaptation. At this stage there are several hypotheses as to the nature of the mechanism
In the long term new Insect Resistance Management strategies likely more complex should be developed against Busseola fusca.
Such perspectives could include a more diverse array of toxins for the control of pest populations possibly supplemented with a biological component such as pathogenic fungi or parasitic wasps.
and now this demand is being linked to the contamination of Central america's crocodilians. New research published in Environmental Toxicology
and Chemistry analyses blood samples from spectacled caiman in Costa rica and finds that intensive pesticide use in plantations leads to contaminated species in protected conservation areas.
Tortuguero is home to the spectacled caiman (Caiman crocodilus) one of the most common species of crocodilian in Central america.
This freshwater predator is known to be highly adaptive feeding on fish crustaceans and in the case of larger specimens wild pigs.
The team collected blood samples from 14 adult caiman and analyzed them for traces of 70 types of pesticide.
Caiman within the high intensity banana crop watershed of Rio Suerte had higher pesticide burdens relative to other more remote locations.
The nine pesticides detected in the caiman blood were identified as insecticides. Of these seven were listed as Persistent Organic Pollutants (POPS) banned under the 2011 Stockholm Convention.
Caiman near banana plantations had higher pesticide burdens and lower body condition said Grant. This suggests that either pesticides pose a health risk to caiman
or that pesticides harm the habitat and food supply of caiman thereby reducing the health of this predator.
As long-lived species atop the food chain crocodilians provide an integrated assessment of the fate of pesticides in tropical areas
and can be indicative of pesticide damage throughout the ecosystem. Caiman and other aquatic species have been exposed to pesticides from upstream banana plantations even in remote areas of a national wilderness area concluded Grant.
Banana plantations may be economically important to Costa rica; however their erosion of aquatic ecosystems highlights the need for a developed regulatory infrastructure and adequate enforcement.
but this cannot be concluded definitively as MRSA can be transferred between the animals during transport. MRSA found in tank milk from dairy cattle Last year was the first year that tank milk was examined for the presence of MRSA.
Staphylococci are bacteria found in humans animals and in our surrounding environment. Staphylococcus aureus is part of the normal nasal and skin flora in approx. 50%of the population.
Animal and meat production in Denmark A large majority of the meat products produced in Denmark come from pigs.
#X-ray science taps bug biology to design better materials and reduce pollutionbug spray citronella candles mosquito netting--most people will do anything they can to stay away from insects during the warmer months.
Researchers using the cutting-edge X-ray technology at the U s. Department of energy's Advanced Photon Source (APS) were able to take an inside look at several insects gathering results that go beyond learning about insect physiology and biology.
What they found could provide a blueprint for a material used for artificial ligaments a chemical-free way to protect crops from insects and a new insight on how human muscles function.
Most people know the caddisfly as the artificial bug on fly fishing lures. But few know that these real caddiesflies spin an adhesive silk underwater to build nets to capture food and build protective shelter.
The chemical structure of the silk allows the substance to adhere to most substances underwater.
and physics at Arizona State university and author of a study in Biomacromolecules that examined caddisfly silk.
They found that at the molecular level caddisfly silk differs greatly from other terrestrial spun silks such as those from spiders or silkworms.
Caddisfly silk is phosphoratelated meaning that after the amino acid chain that makes up the silk is created phosphate molecules bond to the chain.
Putting grasshoppers on a diet Grasshoppers eat up crops but farmers may soon have a chemical-free way to protect their plants from these voracious pests by turning their natural growth cycle against them.
Scott Kirkton associate professor of biology at Union College observed that just before molting a growth process in
which an insect sheds its skin in order to mature to its next life stage a grasshoppers insides become essentially too large for its outer shell.
This compresses the grasshopper's tracheal system and makes it difficult for it to breathe.
As a result the team saw a reduction in the number of jumps per minute for the grasshoppers about to molt
versus those that were not suggesting that a compressed respiratory system causes a reduction in mobility.
From this Kirkton hypothesizes that a lack of oxygen delivery to the grasshopper's body is a trigger for molting.
Storing grains or crops at low oxygen levels would limit the oxygen the insects get
The resulting stunted growth cycle would create petite pests with petite appetites leaving more crops to make their way to supermarket shelves.
and reduce the overall lifespan of the insect Kirkton said. The key to discovering the connection between oxygen
and quantify the functioning respiratory system of an intact living insect in real time. Kirkton published recently in the Journal of Comparative Physiology his look at the respiratory system of the American grasshopper during periods right before molting.
While Kirkton says that more research needs to be done he thinks that this finding is applicable to a wide-range of insects
which means a universal and chemical-free pest control method may be on its way. Muscled mothsalthough few gym rats want to admit it whispery moth wings
and bulging human biceps aren't that different. What we learn from them can teach us more about human muscle mechanics to potentially improve physical therapy treatments
and further understand diseases attacking the muscular system. But logistically looking at the protein structures within a moth's muscle cells is no easy task.
The experiment setup involved gluing a moth by its thorax to a support structure attaching a series of electrodes to its flight muscles to trigger its wings to beat at a rapid pace
and then using one of the world's most powerful light sources to examine the molecular structure of its muscle movement in real time.
The results shed light on more than the mechanics of moth flight--it may redefine our understanding of how our own muscles function.
and author of a study in Science that examined the cross bridge cycling in the muscles of moths had to seek out Thomas Irving.
and experience hooking up insects to gizmos--that helped Daniel pull together this experiment. What they found was that
when a moth flaps its wings a bit of a tug of war is happening at a molecular level.
and his team observed that the top of the moth's thorax which is the muscle that makes the wings move was cooler on top than on the bottom.
This energy transfer process allows the moth to fly without expending a large amount of energy. Daniel says that the presence of elastic energy was not a surprise.
and no insect would be able to maintain that kind of energy output. However this study uncovers a new mechanism for this elastic energy storage one based on temperature differences.
At a molecular level a moth's muscle is not very different than a human's meaning that elastic energy may serve a much larger role in human muscle function than researchers previously thought.
and shirts to prevent skin irritation while keeping allergy-causing stinging insects away. Choose Wisely--The worst allergy offenders might be in your own yard.
Through carbon credit sales from avoided deforestation the Makira REDD+Project will finance the long-term conservation of one of Madagascar's most pristine remaining rainforest ecosystems harboring rare and threatened plants and animals
which contains an estimated one percent of the world's biodiversity including 20 lemur species hundreds of species of birds
'Only by viewing forest sites along a gradient of logging disturbance ranging from pristine to heavily degraded were the team able to detect a gradual decline of some key bat species. The research confirmed the most vulnerable bats were those that tend to live in the cavities of old growth trees.
By linking bat captures with vegetation measurements from nearby plots the researchers were able to reveal how these animals declined as successive rounds of logging took their toll on forest structure and crucially the availability of tree cavities.
'For biodiversity simple measures such as setting artificial nest boxes for bats and birds may if guided by research help bring some species back to the numbers found in unlogged areas'he said.
and ancestral genetic toolkit that enabled animals and fungi to evolve into diverse multicellular life forms.
Jeffrey Silberman a professor of biological sciences isolated a new unicellular anaerobic eukaryote and worked with former graduate student Matt Brown and others in the lab of Andrew Roger at Dalhousie University in Halifax Nova scotia Cananda on the genomics and description of this organism
and proteins that most people think are specific to being multicellular in animals are already present in their unicellular relatives.
and modified bit by bit in the single-cell lineages that share a common ancestry with animals.
Silberman and Brown study the origins and relationships among single-celled eukaryotes which have nucleus amoebae and flagellates some
of which are parasites. Animals plants and fungi are all eukaryotes; that is they have complex cells with organelles such as a nucleus and mitochondria.
Eukaryotes and humans have more in common than most people realize Silberman said. Silberman and Brown perform comparative DNA sequence analyses of a type of eukaryote called protists to help find their particular placement or branch on the tree of life.
By isolating formerly unexamined anaerobic protists--a diverse group of unicellular microorganisms --and looking at the independent ways they have formed different types of mitochondria the researchers hope to reveal essential commonalities among all eukaryotes perhaps even clues that explain their origin.
Genomic analyses of single cell organisms that are specifically related to multicellular lineages often provide clues to understanding the molecular mechanisms involved in the evolution of multicellular life.
To characterize the new organism which was collected from brackish sediment in Prince Cove in Marstons Mills Mass. the researchers described the morphology
and sequenced the protein-coding genes of the organism to construct a 159-protein matrix for phylogenetic analyses.
which is a unicellular eukaryote but distinguished itself with its conspicuous long flagella. Most importantly the phylogenetic tree established the organism as a distant
but unequivocal relative to a supergroup of eukaryotes that include fungi and animals. It provides a glimpse of the various components of cell-to-cell adhesion
which in animals plays a key role in cell-to-cell signaling and adhesion to the extracellular matrix.
We increasingly recognize the fact that we share a common environment with the animals we keep
and of the concept of'One Health'in action--controlling infections in animals can have a major impact on public health.
and about 75 percent of the antibiotics consumed by the animals. For the study researchers utilized Geisinger's sophisticated electronic health record system to identify patients with MRSA infections and skin and soft tissue infections.
Patients received an exposure score based on their distance from the production the number of animals at livestock operations the amount of manure spread on crop fields and the size of the field.
#Model of dangerous bee disease in Jersey provides tool in fight against honeybee infectionsscientists at the University of Warwick have modelled an outbreak of the bee infection American foulbrood in Jersey using a technique
which could be applied to other honeybee diseases such as European foulbrood and the Varroa parasite. As well as modelling how bee infections spread the method also allows scientists to simulate various disease control interventions in order to measure their efficacy.
which affects the larval stage of honeybees. It can cause the death of an entire hive within a matter of monthsthe Jersey data covered 450 honeybee hives their location
and their owners from which the researchers built a computer simulation which modelled the speed at
Honeybees are one of the most important bee species in the world in terms of their contribution to food production through pollination.
which can wipe out a hive within a few months. By understanding how it is spreads from hive to hive we then have a good basis to formulate interventions.
This is the first rigorous statistical analysis carried out on a honeybee disease epidemic that we are aware of.
The model suggests that just under half of the 2010 Jersey infection spread was attributed to transmission by owners between their own hives.
The researchers suggest that distance between colonies was another important factor in the spread of the disease with the disease mostly spreading between hives less than 2km apart.
The model also simulated the impact of different control strategies on controlling the epidemic and found that the measures taken by authorities in Jersey at the time--to inspect
These benefits may include for example reduced pollution outflow and erosion and better wind protection pest control and pollination.
This is what happened with the soil-living social amoeba Dictyostelium discoideum or Dicty. The single-celled amoebas crawl through the soil eating bacteria until food becomes scarce.
Then the amoebas gather by the tens of thousands to form a multicellular slug which transforms itself into a fruiting body:
a sterile stalk that holds aloft a sorus a tiny sphere that releases spores that become single amoebae again.
but some clones (genetically identical amoebas) also farm them --or at any rate they gather up the bacteria carry them to new sites and harvest them prudently.
Amoebas carrying seed corna lot of work has been done on this organism said Debra Brock a research scientist in the Queller/Strassmann lab
It looked like the amoebas were carrying the bacteria around to make sure they would always have food.
After all the amoebas are grown on bacteria in the lab; perhaps they had picked just up these bacteria by accident.
Amoebas carrying chemical weaponsbut the situation was actually more complex than this. Brock quickly realized that some of the bacteria found in association with the Dicty weren't edible.
Were these bacteria parasites on the amoebas? Were they free riders the amoebas picked up accidentally
when they picked up the food bacteria? Were they pathogens that were making the amoebas sick?
But the amoebas carrying these bacteria seemed to be thriving rather than sick. And she also knew that in other systems farmers carry defensive symbionts.
Leafcutter ants for example carry bacteria that help prevent other fungi from contaminating their fungal gardens.
Could the inedible bacteria on the Dicty be defensive symbionts? Sure enough assays showed that when farmers carried certain nonedible strains nonfarmer spore production was reduced in some cases by more than half.
Brock suspects the amoebas and the bacteria are cross feeding. They're probably providing something for those bacteria
--if the amoebas are dispersed to a site without a good source--farmers produce more spores than nonfarmers
These results suggest that social amoebas make farming pay much as human farmers all over the world have done by privatizing their crops.
which are more acutely toxic to birds and mammals with uses that include home insect control insect-repellant clothing dog and cat flea shampoos mosquito control and agriculture.
The growing use led Ohlinger and colleagues to check on the effectiveness of advanced sewage treatment processes in removing pyrethroids from wastewater from a sewage treatment plant.
Old bicycle wheel and lab motor used in experiment Fish school primarily for protection from predators
A profusion of tree and plant species as well as one third of Peru's mammal bird and frog species make their home in these perennially wet regions located along the eastern slopes of the Andes mountains.
#Australian tarantula venom contains novel insecticide against agricultural pestsspider venoms are usually toxic when injected into prey
but a new protein discovered in the venom of Australian tarantulas can also kill prey insects that consume the venom orally.
The protein is strongly insecticidal to the cotton bollworm an important agricultural pest according to research published September 11 in the open access journal PLOS ONE by Glenn King and Maggie Hardy from the Institute of Molecular
The small protein named orally active insecticidal peptide-1 (OAIP-1) was found to be highly toxic to insects that consumed it with potency similar to that of the synthetic insecticide imidacloprid.
Cotton bollworm a pest that attacks crop plants was more sensitive to OAIP-1 than termites and mealworms
These and other insect pests reduce global crop yields by 10-14%annually and damage 9-20%of stored food crops
Isolated peptides from the venom of spiders or other venomous insectivorous animals such as centipedes and scorpions may have the potential to serve as bioinsecticides.
Alternately the authors suggest the genes encoding these peptides could be used to engineer insect-resistant plants
or enhance the efficacy of microbes that attack insect pests. King elaborates The breakthrough discovery that spider toxins can have oral activity has implications not only for their use as bioinsecticides
but also for spider-venom peptides that are being considered for therapeutic use. Story Source: The above story is provided based on materials by Public library of Science.
Note: Materials may be edited for content and length. Journal Reference e
#Crop-raiding elephants flee tiger growlswild Asian elephants slink quietly away at the sound of a growling tiger
but trumpet and growl before retreating from leopard growls researchers at the University of California Davis have found.
The work published Sept. 11 in the journal Biology Letters could help Indian farmers protect their crops from marauding elephants and save the lives of both people and animals.
We noticed that the elephants were scared more of tigers than of leopards said Vivek Thuppil who carried out the work with Richard Coss professor of psychology at UC Davis as part of his Ph d. in animal behavior.
Thuppil and Coss studied the elephants'behavior in an effort to prevent conflicts between human farmers
and elephant herds that raid their fields by night. It's the first study of nighttime antipredator behavior in elephants.
Crop raiding by elephants is a serious problem in India Thuppil said. Farmers use drums firecrackers
and electrified fences to try to keep them out of their crops. About 400 people a year are killed during these encounters
and some hundred elephants are killed through poisoning electrocution or other means according to an Indian government report.
The researchers set up equipment to play back leopard or tiger growls triggered when the elephants crossed infrared beams across paths leading to crop fields
and captured the events on video. Leopards aren't known to prey on elephants but tigers will sometimes attack a young elephant that becomes separated from the herd.
Although their initial reactions were very different the elephants ultimately retreated from growls of both cats.
The elephants might be confused by the leopard growl Thuppil said. A real leopard would most likely retreat from a group of elephants.
Still there's probably no benefit to the elephants in risking an encounter with a leopard
even if it is known not a predator. You don't want to mess with something with claws and teeth Thuppil said.
They're acting in a very intelligent way Coss said. Wild elephant populations are stable
or even increasing in forest areas Thuppil said. While the forest itself is protected human settlement increasingly has moved into the buffer areas surrounding the forest
which elephants pass through while foraging or visiting different patches of forest. The work was supported by the U s. Fish and Wildlife Service Asian Elephant Conservation Fund and the Rufford Small Grants Foundation.
Story Source: The above story is provided based on materials by University of California-Davis. Note: Materials may be edited for content and length h
#Climate change may speed up forests life cyclesmany climate studies have predicted that tree species will respond to global warming by migrating via seed dispersal to cooler climates.
But a new study of 65 different species in 31 eastern states finds evidence of a different unexpected response.
Nearly 80 percent of the species aren't yet shifting their geographic distributions to higher latitudes.
Instead they're staying in place --but speeding up their life cycles. The Duke university-led study published online Wednesday in the peer-reviewed journal Global Change Biology is the first to show that a changing climate may have dual impacts on forests.
It adds to a growing body of evidence including a 2011 study by the same Duke team that climate-driven migration is occurring much more slowly than predicted and most plant species may not be able to migrate fast enough to stay one step ahead of rising temperatures.
Contrary to prior assumptions based on examples in mammals and yeast the new research suggests that in plants GÎ
and mammals GÎ interacts with GPCRS of the type that pass through the membrane seven times--7tm receptors.
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