which scientists allowed one group of laboratory rats to feast on potato chips. Another group got bland old rat chow.
Scientists then used high-tech magnetic resonance imaging (MRI) devices to peer into the rats'brains seeking differences in activity between the rats-on-chips and the rats-on-chow.
With recent studies showing that two-thirds of Americans are obese or overweight this kind of recreational overeating continues to be a major problem health care officials say.
In the study while rats also were fed the same mixture of fat and carbohydrates found in the chips the animals'brains reacted much more positively to the chips.
The effect of potato chips on brain activity as well as feeding behavior can only partially be explained by its fat
In the study rats were offered one out of three test foods in addition to their standard chow pellets:
powdered standard animal chow a mixture of fat and carbs or potato chips. They ate similar amounts of the chow as well as the chips
and the mixture but the rats more actively pursued the potato chips which can be explained only partly by the high energy content of this snack he said.
And in fact they were most active in general after eating the snack food. Although carbohydrates and fats also were a source of high energy the rats pursued the chips most actively and the standard chow least actively.
This was further evidence that some ingredient in the chips was sparking more interest in the rats than the carbs
and fats mixture Hoch said. Hoch explained that the team mapped the rats'brains using Manganese-Enhanced Magnetic resonance imaging (MEMRI) to monitor brain activity.
They found that the reward and addiction centers in the brain recorded the most activity.
By contrast significant differences in the brain activity comparing the standard chow and the fat carbohydrate group only appeared to a minor degree
and matched only partly with the significant differences in the brain activities of the standard chow and potato chips group he added.
#Self-medication in animals much more widespread than believedit's been known for decades that animals such as chimpanzees seek out medicinal herbs to treat their diseases.
Animals use medications to treat various ailments through both learned and innate behaviors. The fact that moths ants and fruit flies are known now to self-medicate has profound implications for the ecology and evolution of animal hosts and their parasites according to Mark Hunter a professor in the Department of Ecology and Evolutionary Biology and at the School
of Natural resources and Environment. In addition because plants remain the most promising source of future pharmaceuticals studies of animal medication may lead the way in discovering new drugs to relieve human suffering Hunter
and two colleagues wrote in a review article titled Self-Medication in Animals to be published online today in the journal Science.
When we watch animals foraging for food in nature we now have to ask are they visiting the grocery store
We can learn a lot about how to treat parasites and disease by watching other animals.
which animals such as baboons and woolly bear caterpillars medicate themselves. One recent study has suggested that house sparrows and finches add high-nicotine cigarette butts to their nests to reduce mite infestations.
But less attention has been given to the many cases in which animals medicate their offspring or other kin according to Hunter and his colleagues.
Wood ants incorporate an antimicrobial resin from conifer trees into their nests preventing microbial growth in the colony.
Parasite-infected monarch butterflies protect their offspring against high levels of parasite growth by laying their eggs on anti-parasitic milkweed.
Hunter and his colleagues suggest that researchers in the field should deemphasize the'self'in self-medication and base their studies on a more inclusive framework.
Perhaps the biggest surprise for us was that animals like fruit flies and butterflies can choose food for their offspring that minimizes the impacts of disease in the next generation Hunter said.
There are strong parallels with the emerging field of epigenetics in humans where we now understand that dietary choices made by parents influence the long-term health of their children.
The authors argue that animal medication has several major consequences on the ecology and evolution of host-parasite interactions.
For example when gypsy moth caterpillars consume foliage high in certain toxic compounds transmission of viruses between the caterpillars is reduced facilitating moth outbreaks.
Honeybees are known to incorporate antimicrobial resins into their nests. Analysis of the honeybee genome suggests that they lack many of the immune-system genes of other insects raising the possibility that honeybees'use of medicine has been partly responsible
--or has compensated--for a loss of other immune mechanisms. The authors also note that the study of animal medication will have direct relevance for human food production.
when humans interfere with the ability of animals to medicate they point out. For example increases in parasitism and disease in honeybees can be linked to selection by beekeepers for reduced resin deposition by their bees.
A reintroduction of such behavior in managed bee colonies would likely have great benefits for disease management the authors say.
#Fighting disease from within the mosquito: New techniques to help halt the spread of diseasescientists have revealed a new technique to introduce disease-blocking bacteria into mosquitoes with promising results that may halt the spread of diseases such as dengue yellow fever and potentially malaria.
When infected with the bacteria Wolbachia mosquitoes are unable to spread viruses such as dengue a disease
which kills round 40000 people each year with no vaccines or specific treatments currently available. There have been around 2400 cases of dengue infection in Northern Australia in recent years.
However the bacteria has been difficult to spread within the mosquito population because it reduces the mosquitoes'ability to lay viable eggs.
Now Professor Hoffmann from the University of Melbourne and Professor Michale Turelli from the University of California have shown that by introducing an insecticide resistance gene alongside the Wolbachia bacteria into the mosquito that the insects pass on the disease-blocking bacteria to other mosquitoes faster.
The results are published today in the journal Proceedings of the Royal Society B. This could mean that the spread of disease can be stopped faster
and less infected mosquitoes would need to be released in a disease control program said Professor Ary Hoffmann from the University of Melbourne's Bio21 Institute and Department of Genetics.
Wolbachia bacteria strains live naturally inside up to 70%of all insects and are known to protect them against viral infection.
The disease-blocking strain of Wolbachia was discovered first in Australian fruit flies in 1988 by Prof Hoffmann
and trials with collaborators at Monash and James Cook Universities in 2011 showed that Wolbachia-infected mosquitoes were unable to spread the dengue virus.
and malaria-prone regions and so this strategy should select for the survival of only the Wolbachia-infected mosquitoes
but then these insects would be unable to pass on a virus to humans. Prof Hoffmann added that insecticide resistance genes would not spread to the uninfected mosquito populations
because a Wolbachia-infected female with a resistance gene will always pass on both the gene and the bacteria to her offspring.
and the strategy can utilize insecticides that are no longer part of active mosquito control programs. Story Source:
#Chimpanzees use botanical skills to discover fruitfruit-eating animals are known to use their spatial memory to relocate fruit yet it is unclear how they manage to find fruit in the first place.
which strategies chimpanzees in the Taã National park in CÃ'te d'Ivoire West Africa use
Chimpanzees know that trees of certain species produce fruit simultaneously and use this botanical knowledge during their daily search for fruit.
To investigate if chimpanzees know that if a tree is carrying fruit then other trees of the same species are likely to carry fruit as well the researchers conducted observations of their inspections
which they saw chimpanzees inspect empty trees when they made mistakes. By analysing these mistakes the researchers were able to exclude that sensory cues of fruit had triggered the inspection
and were the first to learn that chimpanzees had expectations of finding fruit days before feeding on it.
The researchers conclude that chimpanzees know that trees of certain species produce fruit simultaneously and use this information during their daily search for fruit.
and an ability to categorize fruits into distinct species. Our results provide new insights into the variety of food-finding strategies employed by our close relatives the chimpanzees
In a paper published online in Nature Neuroscience the U-M team shows that a particular protein called FIP200 governs this cleaning process in neural stem cells in mice.
If the findings translate from mice to humans the research could open up new avenues to prevention or treatment of neurological conditions.
They were using FIP200-less mice as comparisons in a study when an observant postdoctoral fellow noticed that the mice experienced rapid shrinkage of the brain regions where neural stem cells reside.
That effect was more interesting than what we were actually intending to study says Guan as it suggested that without FIP200 something was causing damage to the home of neural stem cells that normally replace nerve cells during injury or aging.
Only by giving the mice the antioxidant n-acetylcysteine could the scientists counteract the effects.
#Bean leaves can trap bedbugs, researchers findinspired by a traditional Balkan bedbug remedy researchers have documented how microscopic hairs on kidney bean leaves effectively stab
and trap the biting insects according to findings published online today in the Journal of the Royal Society Interface.
Scientists at UC Irvine and the University of Kentucky are now developing materials that mimic the geometry of the leaves.
Bedbugs have made a dramatic comeback in the U s. in recent years infesting everything from homes and hotels to schools movie theaters and hospitals.
Their work was motivated by a centuries-old remedy for bedbugs used in Bulgaria Serbia and other southeast European countries.
The bug-encrusted greenery was burned the next morning to exterminate the insects. Through painstaking detective work the scientists discovered that the creatures are trapped within seconds of stepping on a leaf their legs impaled by microscopic hooked hairs known botanically as trichomes.
The synthetic surfaces snag the bedbugs temporarily but do not yet stop them as effectively as real leaves Loudon said suggesting that crucial mechanics of the trichomes still need to be determined.
Theoretically bean leaves could be used for pest control but they dry out and don't last very long.
Plants exhibit extraordinary abilities to entrap insects said Loudon lead author of the paper. Modern scientific techniques let us fabricate materials at a microscopic level with the potential to'not let the bedbugs bite'without pesticides.
Nature is a hard act to follow but the benefits could be said enormous Potter. Imagine if every bedbug inadvertently brought into a dwelling was captured before it had a chance to bite
and multiply. Funding for the study was provided by the National Science Foundation. Story Source: The above story is provided based on materials by University of California-Irvine.
To address the major challenges in managing the growing amounts of animal and human waste water pollution; protecting water resources and restoring an economically vital coastline we will need to invest in the characterization of our water microbiological communities and shift the pollution science paradigm toward an understanding of risk and resilience under global change.
either crystalline or amorphous but these categories were probably more reflec tive of the limitations of imaging methods than the underlying structural organization of the cellulose says Jerome Fox lead author of the Nature Chemical Biology paper
The new PALM-based technique should allow enzyme cock tails to be matched optimally to the structural organizations of particular biomass substrates such as grass
and Fox other co-authors of the paper A single-molecule analysis reveals morphological targets for cellulase synergy were Phillip Jess Rakesh Jambusaria and Genny Moo.
Solazyme's patented microalgae strains have become the workhorses of a growing industry focused on producing commercial quantities of microalgal oil for energy and food applications.
petroleum plants and animals. Producing custom-tailored oils starts with optimizing the algae to produce the right kind of oil
That waste can occur due to spoilage from improper storage of grain during transportation or from pests.
Rats and mice alone eat or spoil 20 percent of the world's food supply due to contamination with their urine and feces.
Developed countries have much more efficient systems for preserving storing transporting and protecting food from spoilage and pests.
Cows horses and termites can digest the cellulose in grass hay and wood. Most cellulose consists of wood fibers and cell wall remains.
#Researchers help unlock pine beetles Pandoras boxtwenty researchers--more than half of them Simon Fraser University graduates
A paper detailing their newly created sequencing of the mountain pine beetle's (MPB) genome will be gold in the hands of scientists trying to stem the beetle's invasion into eastern forests.
just as the mountain pine beetle has been doing to B c.'s lodgepole pines says Christopher Keeling the paper's lead author.
It's the beetle's genome that will help us figure out exactly how it does its damage
As the beetles'range expands and as they head into jack pine forests where the defensive compounds may be different this variation could allow them to be more successful in new environments explains Keeling.
The rice grain-sized insect has already wiped out an area of B c. lodgepole pine forest five times larger than the size of Vancouver Island.
The MPB genome allows us to examine the population differences for beetles at various parts of an outbreak.
The genome sequencing of the first North american pest bark beetle species in the Genus dendroctonus also uncovers a bacterial gene that has jumped into the MPB genome.
and/or microorganisms that grow in the beetle's tunnels beneath the bark of a tree explains Keeling.
Audiences influence future status of quails following fights between rivalsfor animals prevailing in a fight affects their likelihood of winning future conflicts.
This treatment seriously influenced the birds'aggressive behaviour: the losers were chasing the subordinate male in the group to a greater extent
Although through the blocker the testosterone had no effect on these birds temporarily the winners were still able to maintain their social status.
which already include human specimens mice the model plant Arabidopsis thaliana cell lines genes and microorganisms.
because they floated away says Traggis a master's student from Buzzards Bay Mass. While no negative effects have been reported on New england's shellfish industry the researchers note that the region's oyster industry is valued at $117. 6 million The researchers
#Let me introduce myself--leafcutter bee Megachile chomskyi from Texasthe Genus megachile is a cosmopolitan group of solitary bees often called leafcutter bees.
A new species Megachile chomskyi has been found only in Texas US. What is specific and interesting about this bee is the fact that it is among those insects
which exhibit a narrow specialized preference for pollen sources. Presumably the irreplaceable host of M. chomskyi are the beautiful flowers of the widespread Onagraceae or the so-called Evening-primrose family.
Chomsky had inspired the name of another animal the chimpanzee Nim Chimpsky who was a part of an extended study of animal language acquisition at Columbia University.
Unlike the other representatives of the family that chew leaves or flower petals many species of Megachile neatly cut circular pieces of leaves or petals for nest construction.
Nests of Megachile are constructed often within hollow twigs or other similarly constricted natural cavities but some species including members of the subgenus Megachiloides excavate burrows in the ground.
The subgenus Megachiloides still remains one of the most problematic Megachile groups in North america partially due to males
#Bumblebees use logic to find the best flowersscientists at Queen Mary University of London and the Zoological Society of London (ZSL) have discovered why bees copy each other
but it's something that almost any animal could do in the right circumstances says Dr Elli Leadbeater from ZSL's Institute for Zoology.
and joins Queen Mary's School of Biological and Chemical sciences later this year. Most worker bees visit thousands of flowers every day in their search for nectar to feed their queen's brood.
Copying flower colour choices may be a shortcut to success bypassing the exhausting process of exploring each flower to see
Erika Dawson a Phd student at Queen Mary University of London adds: Our study shows how bees use past associations to make decisions about
but almost all other animals including humans are also capable of forming associations. For example we might associate Easter with chocolate or injections with fear.
The above story is provided based on materials by Queen Mary University of London. Note: Materials may be edited for content and length.
#NASA flies radar south on wide-ranging expeditiona versatile NASA airborne imaging radar system is showcasing its broad scientific prowess for studying our home planet during a month-long
#New dual resistant tomatoes fight lethal pests with one-two punchin the battle against thrips Cornell breeder Martha Mutschler-Chu has developed a new weapon:
a tomato that packs a powerful one-two punch to deter the pests and counter the killer viruses they transmit.
The dual resistant insect and virus varieties may reduce or even eliminate the need for pesticides in several regions.
Thrips are tiny insects that pierce and suck fluids from hundreds of species of plants including tomatoes grapes strawberries and soybeans.
Adapting a novel form of insect resistance discovered in a wild plant native to Peru Mutschler-Chu professor of plant breeding and genetics first isolated the resistance.
The acylsugars don't kill the insects but deter them from feeding or laying eggs on the plants.
If some thrips get through with the virus the virus resistance genes are there to mop it up Mutschler-Chu said.
The Cornell thrips-resistant tomato lines with and without the virus resistance genes will be used by Mutschler-Chu
and an interdisciplinary team of eight other scientists from seven other institutions nationwide as part of a new five-year $3. 75 million project to control thrips and TOSPO viruses in tomatoes.
or tweaking virus resistance Mutschler-Chu wants to discover the best package for insect and virus control.
The observations and experiments of the research show that the green crab has filled the void left by the decline of native predators of sesarma crabs the authors said.
In previous research they showed that predator decline has come about because of recreational fishing. Humans have had far-reaching impacts on ecosystems said author Tyler Coverdale a researcher in the lab of lead author Mark Bertness chair of the Department of Ecology and Evolutionary Biology.
The other is that ecologists should account for the power of a predator's threat not just its actual attacks.
Metals in flowers may play role in bumblebee declinebeekeepers and researchers nationally are reporting growing evidence that a powerful new class of pesticides may be killing off bumblebees.
Now research at the University of Pittsburgh points toward another potential cause: metal pollution from aluminum and nickel.
Published in the journal Environmental Pollution the Pitt study finds that bumblebees are at risk of ingesting toxic amounts of metals like aluminum
The Pitt study finds that bumblebees have the ability to taste --and later ignore--certain metals such as nickel
Therefore the insects are exposed to toxins before they even sense the presence of metals. Although many metals are required by living organisms in small amounts they can be toxic to both plants
and animals when found in moderate to high concentrations said Tia-Lynn Ashman principal investigator of the study and professor and associate chair in Pitt's Department of Biological sciences in the Kenneth P. Dietrich School of arts and Sciences.
Beyond leading to mortality these metals can interfere with insect taste perception agility and working memory--all necessary attributes for busy bumblebee workers.
Ashman and George Meindl coauthor of the study and a Phd candidate in Ashman's lab studied bumblebee behavior using the Impatiens capensis a North american flower that blooms in summer.
Its flowers are large producing a high volume of sugar-rich nectar each day--an ideal place for bumblebees to forage.
and aluminum in the flowers'nectar influenced bumblebee behavior Ashman and Meindl used two groups of uncontaminated flowers one group of flowers contaminated by nickel and another contaminated by aluminum.
When a bumblebee visited a flower in an array the entire visitation was recorded as well as the time spent (in seconds) foraging on each individual flower.
However once bumblebees arrive at flowers and sample the nectar they are able to discriminate against certain metals.
and won't pose threats to local animals that pollinate. The paper The effects of aluminum and nickel in nectar on the foraging behavior of bumblebees first appeared online March 6 in Environmental Pollution.
Funding was provided by the Carnegie Museum of Natural history's Powdermill Nature Reserve in Rector Pa. a Botany-In-Action Fellowship from the Phipps Botanical garden and Conservatory in Pittsburgh an Ivey Mcmanus Predoctoral Fellowship
and economically important species. Crustaceans are tiny to very large shelled animals that include crab shrimp and lobster.
The researchers found that these plant-eating animals feast on the nuisance algae that grow on seagrass ultimately helping maintain the seagrass that provides nurseries for seafood.
The grazers also serve as food themselves for animals higher on the food chain. Drifting seaweed usually thought of as a nuisance also plays a part in this process providing an important habitat for the grazing animals that keep the seagrass clean.
Inconspicuous creatures often play big roles in supporting productive ecosystems said Matt Whalen the study's lead author who conducted this work
while at VIMS and is now at the University of California Davis. Think of how vital honeybees are for pollinating tree crops or
if we did not have earthworms. In seagrass systems tiny grazers promote healthy seagrasses by ensuring algae is consumed quickly rather than overgrowing the seagrass.
And by providing additional refuge from predators fleshy seaweeds that drift in and out of seagrass beds can maintain larger grazer populations
These tiny animals by going about their daily business of grazing are integral to keeping healthy seagrass beds healthy.
Our results provide convincing field evidence that grazing by small animals can be just as important as good water quality in preventing nuisance algae blooms and keeping seagrass beds healthy.
or more toxins to fend off insect pests rests on assumptions that don't always apply UA researchers have discovered.
Their study helps explain why one major pest is evolving resistance much faster than predicted
and offers ideas for more sustainable pest control. A strategy widely used to prevent pests from quickly adapting to crop-protecting toxins may fail in some cases
unless better preventive actions are taken suggests new research by University of Arizona entomologists published in the Proceedings of the National Academy of Sciences.
Corn and cotton have been modified genetically to produce pest-killing proteins from the bacterium Bacillus thuringiensis or Bt for short.
if pests adapt rapidly said Bruce Tabashnik a co-author of the study and head of the UA department of entomology.
Our goal is to understand how insects evolve resistance so we can develop and implement more sustainable environmentally friendly pest management he said.
Tabashnik and Carriã re are both members of the UA's BIO5 Institute. Bt crops were grown first widely in 1996 and several pests have already become resistant to plants that produce a single Bt toxin.
To thwart further evolution of pest resistance to Bt crops farmers have shifted recently to the pyramid strategy:
each plant produces two or more toxins that kill the same pest. As reported in the study the pyramid strategy has been adopted extensively with two-toxin Bt cotton completely replacing one-toxin Bt cotton
since 2011 in the U s. Most scientists agree that two-toxin plants will be more durable than one-toxin plants.
and analysis of published experimental data the new results help explain why one major pest has started to become resistant faster than anticipated.
We tested the underlying assumptions of the models in lab experiments with a major pest of corn and cotton.
Redundant killing can be achieved by plants producing two toxins that act in different ways to kill the same pest he said so
if an individual pest has resistance to one toxin the other toxin will kill it.
His home institution the Center for Agricultural Research for Development or CIRAD is interested keenly in factors that could affect pest resistance to Bt crops in Africa.
We obviously can't release resistant insects into the field so we breed them in the lab
For their experiments the group collected cotton bollworm--also known as corn earworm or Helicoverpa zea-a species of moth that is a major agricultural pest and selected it for resistance against one of the Bt toxins Cry1ac.
As expected the resistant caterpillars survived after munching on cotton plants producing only that toxin. The surprise came
If the assumption of redundant killing is correct caterpillars resistant to the first toxin should survive on one-toxin plants
But on the two-toxin plants the caterpillars selected for resistance to one toxin survived significantly better than caterpillars from a susceptible strain.
and may also explain the reports indicating some field populations of cotton bollworm rapidly evolved resistance to both toxins.
Moreover the team's analysis of published data from eight species of pests reveals that some degree of cross-resistance between Cry1
Carriã re explained that this is especially problematic with cotton bollworm and some other pests that are not highly susceptible to Bt toxins to begin with.
The team found violations of other assumptions required for optimal success of the pyramid strategy.
and thus allow survival of susceptible pests Under ideal conditions inheritance of resistance is not dominant
and the susceptible pests emerging from refuges greatly outnumber the resistant pests. If so the matings between two resistant pests needed to produce resistant offspring are unlikely.
But if inheritance of resistance is seen dominant as with cotton bollworm matings between a resistant moth
and a susceptible moth can produce resistant offspring which hastens resistance. According to Tabashnik overly optimistic assumptions have led the EPA to greatly reduce requirements for planting refuges to slow evolution of pest resistance to two-toxin Bt crops.
The new results should come as a wakeup call to consider larger refuges to push resistance further into the future Carriã re pointed out.
Our simulations tell us that with 10 percent of acreage set aside for refuges resistance evolves quite fast
Our main message is to be more cautious especially with a pest like the cotton bollworm Carriã re said.
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