Lack of water makes plants less capable of fending off pathogens and insects. After the 2003 heatwave, caterpillars devastated Mediterranean oak forests near Montpellier in France.
Researchers have presumed that this triggered a large carbon release but such responses are hard to predict.
Around half the country is affected already by the pests (pictured), which threaten large swaths of the island s rice production
Should the virus become established in birds or other animals regular human infections might then occur providing opportunities for the virus to adapt better to humans,
two that encode the haemagglutinin (H) and neuraminidase (N) proteins that stud the surface of the virus,
In the three human cases, the genes coding for the internal proteins seem to come from H9n2 viruses a class that is endemic in birds,
seems to be similar to avian H11n9 viruses that were found in South korea in 2011;
In other words, the new virus seems to stem from a reassortment of three virus strains that infect only birds.
which was a mix of viruses that infect birds, pigs and humans. Most of the genetic analyses are still being carried out confidentially within THE WHO's global flu-research networks.
A striking feature of the novel virus is that its H protein is structurally similar to that of viruses that don t cause severe sickness in birds,
Flu viruses that don t sicken birds can, however, cause severe disease in humans simply because we lack any immunity to them.
scientists say that it seems clear from the sequence that the novel virus has acquired key mutations that permit the H protein to latch onto receptors on mammalian cells in the airways instead of onto avian receptors.
The virus also contains several other genetic variations that are known from past studies in mice and other animals to cause severe disease.
The fact that the virus does not seem to cause serious disease in birds has potential epidemiological and public-health implications,
But it might be almost impossible to control a virus in birds that generates few visible symptoms
China has reported not any recent H7 flu infections in birds, perhaps because such infections would not show up as serious disease,
is to track down which birds or animals the affected humans caught the virus from. H7 viruses are common in wild birds but much less so in poultry.
It therefore seems unlikely that three human cases in such a short space of time could result from contact with wild birds
says Peiris. Domestic fowl are the most likely alternative source of the virus . But given that H7n9 has mutations that enable it to infect mammals,
pigs might be another source, says Tashiro. Flu experts say that other urgent requirements include testing any human cases of serious pneumonia for traces of the virus
and tracking down people who have come into contact with new cases. Among researchers and public-health officials, says Peiris,
Mutant mosquitoes lose lust for human scentmosquitoes that are modified genetically to lack some of their sense of smell cannot tell humans from other animals
and no longer avoid approaching people who are slathered in bug spray. These findings, published online today in Nature1, could help scientists to design insect repellents to combat malaria, dengue and agricultural pests.
Some mosquito species will feed on most animals that they encounter. Aedes aegypti, the mosquito that carries dengue and yellow fever,
and Anopheles gambiae, which hosts the malaria parasites, are choosier: they prefer humans.""They love everything about us,
says Leslie Vosshall, a neurobiologist at The Rockefeller University in New york, who led the latest study."
"They love our beautiful body odour, they love thecarbon dioxide we exhale and they love our body heat.
Mosquitoes have specialized sensing systems for detecting carbon dioxide and body heat, but body odour is the only one of these features that distinguishes humans from other warm-blooded animals.
Leslie Vosshall tells Ewen Callaway what makes humans so yummy for mosquitoes. Vosshall s team genetically engineered A. aegypti mosquitoes to lack the gene orco,
which makes a protein that helps build the receptor molecules that sense many smells. A series of experiments showed that without the Orco protein
the mosquitoes struggled to distinguish the smell of honey from that of glycerol (an odourless liquid of similar consistency),
and humans from other animals.""It s sort of like a game show where the mosquitoes are released into a box
and we ask them to choose door number one, where there s a human arm, or door number two, where there are our beloved guinea pigs,
says Vosshall. The mutant mosquitoes that did pick the scent of the human arm, however, did not hesitate to approach it.
Vosshall says that orco and the smell receptors that it produces are important for picking between hosts,
but not for finding and feeding on them. The engineered mosquitoes were also unable to smell the insect repellent DEET (N
N-diethyl-meta-toluamide) from a distance. A normal mosquito would avoid DEET, but the mutants were shown to land on a human arm slathered in the repellent.
But on landing, instead of settling in for a blood meal, they fled, suggesting that DEET can deter mosquitoes not just via its smell but also via direct contact.
Vosshall s team is now trying to work out which other sensations repel mosquitoes.""It s unbelievable to me that people have been spraying DEET on skin for upwards of 60 years.
We don t have any clear idea of how or why it works, and that as a scientist just drives me crazy,
she says. Laurence Zwiebel, a molecular entomologist at Vanderbilt University in Nashville, Tennessee, says that Vosshall's study shows that DEET does not work by simply blocking the smells that are conveyed by Orco,
because mosquitoes without the gene are attracted still to humans. A more probable scenario is that DEET jams a mosquito s sensory system
he says.""We all know being in a room with too much sensory stimulation is pretty aversive.
Male mosquitoes genetically engineered to produce unviable offspring have shown promise in field trials in reducing populations of A. aegypti.
But Vosshall and Zwiebel dismiss the idea of releasing mosquitoes that cannot discriminate between humans and other animals.
whether it scrambles insects'sense of smell. Almost all insects have orco so a chemical that targets the gene could help to keep pests away from economically important crops."
"We re not looking to kill these insects, per se, we just want them to feed on something else,
says Zwiebel
Long-lived insects raise prime riddledrivers who end up behind John Cooley this week will quickly lose their patience.
Cruising around the eastern United states with his car window open, he slows down or stops every few hundred metres,
cocks an ear and taps on a data-logger strapped into the passenger seat. Since last week, Cooley, an evolutionary biologist at the University of Connecticut in Storrs, has been on the road mapping populations of periodical cicadas (Magicicada.
These loud, red-eyed insects have spent the past 17 Â years maturing underground, only to emerge this month by the billions for a few weeks of singing
and sex before they die. Like a handful of other cicada researchers on the prowl from North carolina to New york, Cooley knows that he has to work quickly."
"Time is the real enemy here, for both the cicadas and the researchers, he says."
"If you miss this opportunity, you have a hole in your map and you have to wait for another 17 years.
The insect genus with the longest known life cycles, Magicicada has confounded scientists for centuries. In 1665, the first volume of Philosophical Transactions of the Royal Society included a report from New england concerning"swarms of strange insects,
and the mischiefs done by them. Charles darwin also puzzled over them. Even now, entomologists are trying to understand how the insects peculiar life cycles evolved,
how they count the years underground and how they synchronize their schedules.""They are one of the big ecological mysteries out there,
says Walt Koenig, a behavioural ecologist at the Cornell University Lab of Ornithology in Ithaca,
Of the thousands of cicada species known around the world, only the seven Magicicada species,
At the southern end of their range, Magicicada populations have split into three mixed-species broods that emerge every 13 Â years.
Brood II cicadas have grown through five larval stages underground, where they survived by sucking fluids from tree roots.
With the warm weather this month, the nymphs have been crawling out of the ground before moulting for one last time and taking wing.
the cicadas can chorus at more than 95 decibels loud enough to harm human hearing as the males woo the females.
The new generations of nymphs will fall to the ground, burrow into the soil and remain there until 2030.
Biologists generally agree that the giant synchronized emergence of periodical cicadas overwhelms potential predators, allowing some of the relatively defenceless insects to reproduce.
And some researchers have proposed that the cicadas have evolved life cycles around prime numbers of years because that arrangement limits the chances that predators will synchronize with the cicadas.
But these ideas do not address why the generations specifically last for 13 Â or 17 Â years.
Koenig suggests that the answer may involve interactions with birds. He and Andrew Liebhold of the US Forest Service in Morgantown, West virginia, analysed 45 years of data from the North american Breeding Bird Survey (W. D. Koenig and A m. Liebhold Am.
Nat. 181,145-149; 2013) and found that bird populations tend to fall during the years in
which periodical cicadas emerge. Birds feed on cicadas, so Koenig expected to find the opposite pattern. He proposes that the masses of cicadas trigger long-term changes in the forest that end up causing bird populations to crash after 13 or 17 Â years.
The mechanism remains a mystery, but Koenig notes that one factor could be the flood of dead cicadas,
whose bodies are 10%nitrogen. The die off sends a pulse of fertilizer into the forest that temporarily enhances plant growth
but could later lead to unfavourable conditions for birds.""It s a pretty weird hypothesis, he admits.
Ron Edmonds/AP Photoa cicada moults for the last time before taking wing. To synchronize their emergence, the nymphs must somehow keep track of how long they have been underground.
Gene Kritsky, an entomologist at the College of Mount St joseph in Cincinnati, Ohio, says that nymphs seem to count the number of times that trees set their leaves in the spring;
in 2007, some Brood XIV cicadas emerged a year early, following a strong winter thaw during which trees produced leaves,
then dropped them and grew new ones in the subsequent spring. But no one knows how cicadas remember the number of years
since they last emerged. Researchers are making more progress in probing the biological mechanisms that allow cicadas to switch their life cycles.
In an analysis of DNA markers published this year (T.  Sota et  al.
Proc. Natl Acad. Sci. USA 110,6919-6924; 2013), a team including Cooley developed an evolutionary tree for Magicicada
and found that the major species groups had repeatedly split into 13-year and 17-year cohorts.
The researchers suggest that those splits are explained by a common genetic mechanism across the species. Chris Simon,
a co-author and evolutionary biologist at the University of Connecticut, plans to follow up those results with several genetic studies, including sequencing the RNA transcripts of genes that are active at different stages in the cicada life cycle.
She is interested particularly in probing the occasional tendency of periodical cicadas to emerge 4 Â years early or late.
These stragglers are easy prey so do not usually survive but Simon and others suggest that the timing mistakes might have given rise to new broods in the past."
Kritsky documented thousands of cicadas appearing last week in a spot where he saw stragglers in 2000,
four years before the city was inundated with the expected 17-year cicadas of Brood X. The arrival of cicadas in the same place this year might mean that an environmental change such as global warming is causing them to emerge early,
The long generations of the periodical cicadas makes studying them difficult, he says.""You would think we d have a lot of answers
Seafood diet killing Arctic foxes on Russian islandan isolated population of Arctic foxes that dines only on marine animals seems to be slowly succumbing to mercury poisoning.
The foxes on Mednyi Island one of Russia s Commander Islands in the Bering sea are a subspecies of Arctic fox (Vulpes lagopus) that may have remained isolated for thousands of years.
the fox population began to crash, falling from more than 1, 000 animals to fewer than 100 individuals today.
Researchers at Moscow State university wanted to find out if the population crash was caused by diseases introduced by the hunters
and their dogs so they teamed up with Alex Greenwood, head of the wildlife diseases department at the Leibniz Institute for Zoo and Wildlife Research in Berlin,
They screened for four common canine pathogens in foxes captured on Mednyi Island and in the pelts of museum specimens of Commander Island foxes.
So the researchers looked at the foxes diet. Mednyi Island foxes subsist by hunting sea birds and scavenging seal carcasses.
Because pollutants such as mercury are known to accumulate in marine animals particularly in the Arctic, they tested the foxes for the heavy metal
and found high levels of it. The foxes'hair had 10 milligrams of mercury per kilogram on average, with peaks of 30 mg kg-1. By comparison,
inland foxes in Iceland had lower levels, of about 3. 5 mg kg-1. Greenwood s team also compared mercury levels in the Mednyi foxes to those in the population on the neighbouring Bering Island,
and in coastal fox populations in Iceland. Levels of mercury were high there, too. But the Bering Island population
and the coastal Icelandic foxes had experienced not the same population crash as their relatives on Mednyi.
The results were published on 7 may in the journal PLOS ONE1. The difference, the researchers think,
is that the Mednyi foxes have no other options for food. Bering Island is bigger than Mednyi, with small mammals such lemmings and voles,
as well as a human population that creates rubbish that the foxes can eat. The Icelandic coastal foxes, likewise, have the option of moving inland to vary their diet."
"It s not so much what they are eating, as where they are eating, says Greenwood."
"The Mednyi foxes may be more susceptible to increasing global mercury levels. But Dominique Berteaux, an Arctic ecologist at the University of Quebec in Rimouski, Canada, cautions that the team has not definitively proved a link between mercury contamination
and the population decline in this study.""It s always been a hypothesis, but it s very difficult to prove,
he says. Study co-author Ester Rut Unnsteinsd  ttir of the University of Iceland in Reykjavik,
who is director of the Arctic fox Center in S Â Ë av  k, Iceland,
Primate pull out Harvard Medical school announced on 23 Â April that it will close its 47-year-old New england Primate Research center in Southborough, Massachusetts.
860 nonhuman primates   mostly macaques   will close by 2015 owing to a cash shortage.
The animals will be transferred to other primate research centres or be maintained on site, say medical-school officials.
Inspections by the US Department of agriculture found that the centre had violated the Animal Welfare Act several times,
with four primate deaths occurring between June 2010 and February 2012. See go. nature. com/zsavjr for more.
barbed wire and guard dogs, swim the world s most expensive and scrutinized fish. These swift-growing salmon have been at the centre of a 18-year,
US$60-million battle to bring the first genetically modified (GM) animal to US dinner tables   a struggle that may be nearing its end.
The fish would be the first GM animal authorized for human consumption. 1989 â Canadian researchers engineer wild Atlantic salmon to overexpress growth hormone. 1995 Aquabounty files an Investigational New Animal
Drug application with the FDA. 2001 â Aquabounty submits its first regulatory study to the FDA. 2009 â The FDA releases guidance for its evaluation of genetically engineered animals as veterinary drugs;
Aquabounty s long struggle has discouraged other US companies from producing GM animals for food. Mark Walton, chief marketing officer at Recombinetics, an animal-biotechnology company in St paul, Minnesota, says that his company will focus initially on medical applications   using modified farm animals as disease models
"I think we will end up eating genetically modified animals of a variety of species, says Stotish."
Pesticides spark broad biodiversity lossagricultural pesticides have been linked to widespread invertebrate biodiversity loss in two new research papers.
Pesticide use has reduced sharply the regional biodiversity of stream invertebrates, such as mayflies and dragonflies, in Europe and Australia, finds a study published today in the Proceedings of the National Academy of Sciences1.
because invertebrates are an important part of the food web. Emma Rosi-Marshall, an aquatic ecologist at the Cary Institute of Ecosystem Studies in Millbrook
and suggests that neonicotinoids accumulate in soil at levels that can kill soil invertebrates such as Eisenia foetida, a type of earthworm.
Goulson's review also cites earlier studies suggesting that grain-eating birds such as partridges may be dying after eating as few as five seeds treated with neonicotinoids.
UK official defends badger cullengland s badgers are once again in the firing line, as pilot culls to control the spread of bovine tuberculosis begin.
and that will cause spillover of TB to other livestock, to potentially domestic animals and potentially to humans.
And in our case the wildlife reservoir is badgers. Defraian Boydthe problem is tuberculosis not badgers.
Badgers happen to be in the middle of this, and unfortunately the methods for dealing with that problem mean we need to reduce the densities of badgers.
We don t have an alternative to that at the moment. I would say, and I have said to them,
that it is based evidence policy. The first line of evidence is the RBCT the large-scale Randomised Badger Culling Trials run in the 1990s
and 2000s that we carried out, which were very extensive and showed the effect that sustained removal of badgers can have on reducing bovine tuberculosis in cattle.
The second main line of evidence is the comparison with other countries that have had similar problems.
And the only difference between Ireland and ourselves is that Ireland is reducing its badger densities.
Some of the people who have been opposed publicly to badger culling were at the meeting. A significant part of that meeting was supportive of the approach that is being taken.
We need to understand the point of contact between the vector and the susceptible animals.
or badgers and the susceptibles are cattle or badgers doesn t matter. It s the badger-cattle interface we need to understand.
And if we understand that well, then we can start to manage it. I would also point to vaccines as well.
Vaccines, at the end of the day, are going to be what allows us to actually eradicate TB. Clearly reducing wildlife populations and killing cattle is not going to actually produce the elimination that we re really striving for.
We probably have to also move to vaccination of badgers. There s an injectable vaccine available at the moment,
. So we need to get an oral vaccine for badgers, and we re still some way from doing that.
This isn t just about badgers and cattle. It s about badgers cattle and farmers. And other members of the public as well they have choices to make.
We have to understand those social dynamics as much as we have to understand the epidemiological dynamics of the disease.
How the chicken lost its penisthe case of the missing bird penis is a longstanding mystery in evolutionary biology.
But the identification of a molecular mechanism that controls penis loss in birds goes some way to solving this conundrum.
Roughly 97%of avian species sport little or nothing in the way of a phallus,
By contrast, ducks boast large and elaborately coiled penises that can measure about half the length of their bodies2.
They found that chickens initially form penises similar to those of ducks but that on about the ninth day of development, the nascent chicken penis called a genital tubercle stops growing
but the team discovered that many of the same genes that drive penis growth in ducks continued to be expressed strongly in chickens.
The results suggest that genital growth in birds is controlled by a common programme that has been customized by evolutionary tweaks in Bmp signalling
female chickens and other birds may have selected males with smaller penises in part to escape forced copulation.
Over time, that preference would have reshaped the genitalia of male birds
Brazil reports sharp drop in greenhouse emissionsbrazil s greenhouse-gas emissions fell nearly 39%between 2005 and 2010,
City life turns blackbirds into early birdsjust as city slickers have paced faster lives than country folk,
so too do compared urban birds with their forest-dwelling cousins. The reason, researchers report today,
and light have altered the city birds biological clocks1. The finding helps to explain prior reports that urban songbirds adopt more nocturnal lifestyles2-4 data that prompted Davide Dominoni, an ecologist at the Max Planck Institute for Ornithology in Radolfzell, Germany,
to investigate whether the birds activity patterns were merely behavioural responses to busy cities or were caused by an actual shift in the animals'body clocks.
For the study published in Proceedings of the Royal Society B, Dominoni and his colleagues set up an experiment with European blackbirds (Turdus merula).
The scientists attached tiny 2. 2-gram radio-pulse transmitters to blackbirds living in Munich, Germany,
as well as to those living in a nearby forest. The transmitters monitored the birds activity for three weeks.
Dominoni found that whereas forest birds started their activity at dawn, city birds began 29 minutes earlier, on average,
and remained active for 6 minutes longer in the evening. Keen to determine these differences were due to physiological changes,
Dominoni collected blackbirds from both locations and placed them into light-and soundproof enclosures. For ten days these enclosures were illuminated with a constant
dim light so the birds had no idea what time of day it was, and their activity patterns were monitored.
The researchers found that the city birds in the enclosures had faster biological clocks than forest birds.
It took the city birds an average of 50 minutes less to go through a full 24-hour cycle of activity than it took forest birds.
And without the external stimuli of dawn and dusk, the urban birds behavioural rhythms weakened rapidly,
with their periods of activity and rest becoming more irregular than those of the forest birds.
Having such weakly set biological clocks could be a boon for the blackbirds.""It could make them better at coping with city environments that are not as predictable as the wilderness,
says Dominoni. But such clocks could also potentially have adverse health effects. Â"You have to wonder
if these city birds are not compensating by napping during the day or sleeping more deeply at night, is sleep deprivation reducing their cognitive abilities or shortening their life spans?
says Niels Rattenborg, an avian sleep biologist at the Max Planck Institute for Ornithology in Seewiesen,
who was associated not with the study. Still to be determined, Dominoni says, is whether humans who live in cities also have altered circadian rhythms.
Others wonder whether birds biological clocks are altered permanently by city life.""I d be interested really in seeing an experiment where urban birds are transplanted to a rural environment,
and vice versa, says Daniel Mennill, an ornithologist at the University of Windsor in Ontario, Canada."
"Would the urban birds continue to wake up early? Would country birds change? We just don t know
Plastic wood is no green guaranteeishmael Tirado watches as his fellow construction workers rebuild the Steeplechase Pier, a central feature of New york s iconic Coney island boardwalk.
The European Food safety Authority in Parma, Italy, concluded in May that maize (corn) seeds treated with fipronil pose a high acute risk to honeybees. ips trial approved On 19 july, Japan s health minister,
Source: UK Home Officethe number of research procedures involving animals in the United kingdom has continued to rise,
The 8%increase over 2011 figures was driven largely by greater use of genetically modified and other mutant animals.
Mice accounted for 76%of the 4. 03 Â million animals that were used for the first time last year in procedures including breeding and experiments.
28 july-1 august Scientists discuss conflicts between humans and wildlife at the 50th annual conference of the Animal Behavior Society in Boulder,
Millions of migratory birds overwinter here, and it is a precious spawning and feeding ground for more than 60 Â fish species including the critically endangered Chinese sturgeon (Acipenser sinensis).
and burrowing invertebrates, eating mudflats and drying up wetlands. At Dongtan,"this has had devastating consequences for many bird species,
says Ma Zhijun, an ornithologist at Fudan University in Shanghai. The reed parrotbill (Paradoxornis heudei) which nests on native reeds
The shrinking of mudflats also threatens the hundreds of thousands of migratory shorebirds that rely on the reserve as a stopover site.
Crucially, they worry that a permanent barricade will cripple efforts to restore tidal habitats for birds.
For example, without the ebb and flow of tides, the sea bulrush (Scirpus mariqueter), a native intertidal grass bearing fruit and stalks that are key food sources for many birds
and will create more habitats for birds.""It s a better option if the alternative is to do nothing,
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