MON Â 810, an insect-resistant maize (corn; and Amflora, a starchy potato used in the paper industry.
Genome reveals comb jellies'ancient originanimals evolved gradually, from the lowly sponge to the menagerie of tentacled,
This idea makes such intuitive sense that biologists are stunned now by genome-sequencing data suggesting that the sponges were preceded by complex marine predators called comb jellies.
Although they are gelatinous like jellyfish, comb jellies form their own phylum, known as ctenophores. Trees of life typically root the comb jellies'lineage between the group containing jellyfish
and sea anemones and the one containing animals with heads and rears which include slugs, flies and humans.
Comb jellies paddle through the sea with iridescent cilia and snare prey with sticky tentacles. They are much more complex than sponges they have nerves, muscles, tissue layers and light sensors, all of which the sponges lack."
"It s just wild to imagine that comb jellies evolved before sponges, says Billie Swalla, a developmental biologist at the University of Washington in Seattle and a leading member of the team sequencing the genome of the comb jelly Pleurobrachia bachei.
But the team is suggesting just that, in results they presented at the annual meeting of the Society for Integrative and Comparative Biology,
held on 3-7 january in San francisco, California. Despite comb jellies'complexity, DNA sequences in the Pleurobrachia genome place them at the base of the animal tree of life, announced Swalla's colleague Leonid Moroz
a neurobiologist at the University of Florida in Gainesville. Another team presented results from genome sequencing for the comb jelly Mnemiopsis leidyi,
and found that the phylum lands either below, or as close to the base as, sponges on the tree."
"We ve always thought that predator-prey interactions and sensory adaptations evolved long after the origin of sponges,
Swalla says.""Now we need to imagine early life as a sponge, ctenophore and everything in between.
Because millions of species have gone extinct since animals appeared some 542 million years ago, Swalla says,
the ancestor of all animals might look different from modern comb jellies and sponges. Gene families, cell-signalling networks and patterns of gene expression in comb jellies support ancient origins as well.
For example, Moroz and his team found that comb jellies grow their nerves with unique sets of genes."
"These are aliens, Moroz jokes. He suggests that comb jellies might be descendants of Ediacaran organisms,
mysterious organisms that appear in the fossil record before animals. Indeed, in 2011, palaeontologists claimed that one of these 580-million-year-old fossils resembled comb jellies1.
Andy Baxevanis, a comparative biologist at the US National Human genome Research Institute in Bethesda, Maryland,
and a leader on the Mnemiopsis genome project, says that comb jellies are the only animals that lack certain genes crucial to producing microrna short RNA chains that help to regulate gene expression.
Moreover, he points out sponges and comb jellies lack other gene families that all other animals possess2,
3. If comb jellies evolved before sponges, the sponges probably lost some of their ancestors'complexity.
Alternatively, says Sally Leys, a biologist at the University of Alberta in Edmonton, sponges may have complexity that scientists have yet to appreciate."
"A lot of sponges are more exquisite than a lump on a rock, she says. Sceptics wonder whether a high rate of genetic mutation in comb jellies might be causing the lineage to seem closer to the bottom of the tree than it really is."
"In the analyses I ve done, ctenophores are the most problematic taxon. They jump around depending on
which genes you use and which animals you include, says Gert WÃ rheide, a molecular palaeobiologist at the Ludwig Maximilian University of Munich in Germany.
At the meeting, WÃ rheide presented a tree of life created by comparing ribosomal protein sequences.
In it, sponges remained rooted in their bottommost spot
Bumblebees sense electric fields in flowersas they zero in on their sugary reward, foraging bumblebees follow an invisible clue:
electric fields. Although some animals, including sharks, are known to have an electric sense, this is the first time the ability has been documented in insects.
Pollinating insects take in a large number of sensory cues, from colours and fragrances to petal textures and air humidity.
Being able to judge which flowers will provide the most nectar, and which have already been plundered by other pollinators,
helps them to use their energy more efficiently. It has long been known that bumblebees build up a positive electrical charge as they rapidly flap their wings;
when they land on flowers, this charge helps pollen to stick to their hairs. Daniel Robert, a biologist at the University of Bristol, UK, knew that such electrical interactions would temporarily change the electrical status of the flowers
but he did not know whether bumblebees were picking up on this. Keen to find out, he and a team of colleagues measured the net charges of individuals of Bombus terrestris, a common species of bumblebee,
by using sucrose to lure them into a Faraday pail an electrically shielded bucket that reacts to the charge of anything inside it.
As expected most bumblebees were carrying a positive charge. Next, the team placed the insects into an arena with petunias (Petunia integrifolia)
and measured the flowers'electrical potentials. Sure enough, when the bees landed, the flowers became a little more positively charged.
Finally, the team released bumblebees into an arena with artificial flowers, half of which were carried positively charged and a sucrose reward,
and the other half of which were grounded and carried a bitter solution. Over time, the bees increasingly visited the rewarding charged flowers.
But when the researchers turned off the electrical charge on the flowers and re-released the trained bees,
the insects visited rewarding flowers only about half of the time, as they would have by random chance.
That suggested that the bees were detecting the electric fields and using them to guide their activities,
rather than relying on other clues such as fragrance. The team reports its results in this week's Science1."
"We think bumblebees are using this ability to perceive electrical fields to determine if flowers were visited recently by other bumblebees
and are therefore worth visiting, says Robert."We had no idea that this sense even existed,
says Thomas Seeley, a behavioural biologist at Cornell University in Ithaca, New york. Assuming we can replicate the findings,
this is going to open up a whole new window on insect sensory systems for us to study. Some experts suggest that the study has implications for insects other than bees."
"If you think about it, these discoveries could also apply to hoverflies and moths, says Robert Raguso, a chemical ecologist also at Cornell.
We don t know if they can perceive charge differentials, but they burn a lot of energy while hovering around looking for pollen or nectar.
So it would make sense for them to attend to such cues
Nitrogen pollution soars in Chinanitrogen-containing pollutants from agriculture, transport and industry in China has increased by more than half in 30 years,
a study shows, adding to concerns about the country s deteriorating environment.""Rapid economic growth in China has driven high levels of nitrogen emissions in the past few decades,
says Zhang Fusuo, an agriculture researcher at the China Agricultural University in Beijing and a co-author of the study.
Once emitted into the air, key nitrogen pollutants ammonia and nitrogen oxides can be transformed to secondary pollutants such as ammonium and nitrates,
and then washed to Earth by rain and snow. The process, known as nitrogen deposition, can do great damage to ecosystems,
or a cell culture or a transgenic animal and using it to generate thousands more to sell again at a fraction of the original price."
Face-to-face with the earliest ancestor of all placental mammalsafter an asteroid killed off the dinosaurs save for those that evolved into today's birds a small,
furry animal scurried through the forest in search of insects. Its unassuming looks gave little hint that its descendants would one day rule the planet.
A team of scientists in the United states and Canada has reconstructed now the appearance and anatomy of this creature the forebear of all'placental'mammals,
furry-tailed insect eater that weighed between 6 and 245 grams. It gave birth to blind, hairless young, one at a time.
"The fact that it s a small scrambling animal isn t a surprise, she adds,
confirms that the placentals diversified a few hundred thousand years after the (non-avian) dinosaurs went extinct,
so groups such as rodents and primates never shared the planet with the prehistoric reptiles. This conclusion is backed up by the fact that no one has ever found fossils of placental mammals from before the extinction of the dinosaurs 65 million years ago
but it contradicts genetic studies that put the group s origin at around 100 million years ago.
These included traits from 86 living and extinct mammals.""The data matrix that they've assembled is jaw-dropping,
"It undoubtedly provides one of the best estimates of evolutionary relationships within placental mammals to date. The team took two years just to identify the characteristics that they wanted to analyse,
and someone working on whales might call it something else. The researchers bolstered their anatomical results with DNA,
The resulting tree for placental mammals could help to resolve some longstanding debates. For example, it suggests that the treeshrews
and flying lemurs are equally closely related to primates, which include humans. Genetic studies had suggested that flying lemurs were related most closely.
The placental tree also shows that the Afrotheria, the group of African mammals that includes elephants
and aardvarks, evolved from ancestors in North and South america that are now extinct. This creature must have been around after the supercontinent of Gondwana split into today s southern land masses,
so its descendants must have swum or otherwise travelled over long distances to explain the wide distribution of placentals today."
"What fascinates me most is the tremendous incongruence between the morphological and molecular data, says Mark Springer, an evolutionary biologist at the University of California, Riverside.
For example, grouping animals according to their anatomy alone puts physically similar species such as pangolins, anteaters and aardvarks in the same tight group,
Bininda-Emonds adds that the team estimated the timing of the placental evolutionary explosion using just fossil information
Will we kill off today's animals if we revive extinct ones? An article by Scientific American.
The rebirth of an extinct frog species may come from the freezer, not the stomach.
The gastric brooding frog, when it existed On earth, swallowed its eggs, transformed its stomach into a womb
But the frog disappeared from the mountains of southern Australia shortly after it was discovered in the 1970s,
While tadpoles may be a long way off, let alone a viable frog, the southern gastric brooding frog might be the first species brought back from the dead permanently.
The first de-extinction happened in 2003, although it lasted all too briefly. Scientists coaxed a clone of an extinct ibex from Spain to birth from a special hybrid goat.
A lighthouse keeper's cat Tibbles aided by a few feral cats perhaps caught and killed nearly every single Stephens Island wren
just as they were discovered by science in 1900. Hungry sailors ate the Steller's sea cow to death within a century of its discovery.
The Xerces Blue butterfly disappeared with the sand dunes from San francisco in the 1940s as that city swelled.
The American chestnut, once the most abundant tree in eastern North america, succumbed to a fungal blight imported from Asia by humans.
and others, ranging from synthetic biologist George Church of Harvard Medical school to environmental gadfly Steward Brand of the Long Now Foundation
as Archer is attempting to do with the gastric brooding frog. Their first target is the passenger pigeon,
which once was so abundant it darkened the skies of eastern North america. A similar bid by scientists in South korea to revive the woolly mammoth an even more scientifically challenging feat
because it has been extinct for thousands of years may garner the most attention, however. And no need to stop there;
or even sabre-tooth cats although species that have been extinct for more than a few thousand years are unlikely to be found preserved with enough DNA intact to permit their restoration.
or egg cells that bear the DNA of endangered or extinct species and can provide the genetic code to restore
and finally grows into a mammoth, however, is a process still beyond even the most advanced genetic science.
There is also the mammoth challenge of restoring the world or at least the ecosystems that the elephant relatives inhabited, among other hurdles.
And given the perilous plight of still extant elephant species, humanity has yet to show that it can manage the survival, let alone the revival, of a pachyderm.
Still, there are lessons to be learned from the mammoth, not least the importance of cold. The Arctic is the best place for the long-term preservation of DNA,
Shapiro said. It's cold and it's been cold for at least the last million years.
the cold of the San diego's frozen zoo may be the key to ensuring that today's biodiversity makes it through the next few centuries of the Anthropocene intact.
This ark maintained at a steady-197 degrees Celsius, holds the cells of 503 mammals, 170 birds, 70 reptiles and 12 amphibians and fish out of an estimated 10 million animal
At this moment, brave conservationists are risking their lives to protect forest elephants from armed poachers, noted biologist David Ehrenfeld of Rutgers University at TEDX.
And we're talking in this safe auditorium about bringing back the woolly mammoth
Wildlife trade meeting endorses DNA testing of seized ivoryif you go into a bar in Bangkok tonight,
An international meeting that takes place every three years to regulate trade in endangered animals and plants has bolstered protection for a number of species. Besides agreeing to clamp down more strongly on the trade in ivory and rhino horn,
the states party to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) took the unprecedented step of granting protection to sharks and various species of tropical timber tree in their final vote today.
Before the conference researchers across the world had warned of the dire state of African elephant populations,
which are currently being decimated by rampant poaching. Many urged CITES to mandate forensic examination of large seizures of illegal ivory.
UK and has been involved heavily in the debates about elephant poaching, said,"I think this is one of the best COPS
says Samuel Wasser, director of the Center for Conservation Biology at the University of Washington in Seattle and one of the driving forces behind the push for forensic examinations of elephant ivory.
UK and the founder of the charity Save the Elephants, based in Nairobi.""For the first time in 22 years there was no proposal to sell ivory.
Enforcement of rhino protection is also to be strengthened, with Mozambique and Vietnam now required to toughen up their controls on trade in horns.
says Thomas Stocker, a climate researcher at the University of Bern, and a co-chair of a working group of the Intergovernmental Panel on Climate Change."
Stocker says. But with the economic crisis casting a shadow over Europe s Earth -and climate-observation plans, there is little chance of that.
Humans are not the only copycatsa team led by Erica van de Waal, a primate psychologist at the University of St andrews,
UK, created two distinct cultures'blue'and'pink'among groups of wild vervet monkeys (Chlorocebus aethiops) in South Africa1.
The researchers trained two sets of monkeys to eat maize (corn) dyed one of those two colours
Baby monkeys ate the same colour maize as their mothers. Seven of the ten males that migrated from one colour culture to another adopted the local colour preference the first time that they ate any maize.
The only immigrant to buck this trend was a monkey who assumed the top rank in his new group as soon as he got there
"The take-home message is that social learning learning from others rather than through individual trial and error is a more potent force in shaping wild animals behaviour than has been recognized so far,
says Frans de Waal, director of the Living Links Center at the Yerkes National Primate Research center at Emory University in Atlanta,
In the second study, a team led by St andrews marine mammal science student Jenny Allen examined 27 years of whale-watching data from the Gulf of Maine, off the eastern coast of the United states,
to determine whether social cues helped an innovative feeding method to proliferate among humpback whales (Megaptera novaeangliae) 2. Humpbacks everywhere feed by blowing bubbles under schools of fish,
When the whales lunge upward, they can gulp down a super-sized serving of fish.
a humpback slapping the surface of the water with its tail fluke before proceeding with a standard bubble feed.
but by 2007,37%of the humpbacks in the Gulf of Maine were observed using the technique,
Allen and her colleagues applied a method called network-based diffusion analysis to observations of humpback behaviour collected by the Whale Center of New england in Gloucester, Massachusetts, between 1980 and 2007.
Allen's analysis found that up to 87%of whales that adopted the lobtail-feeding technique learned it from other humpbacks."
"We know that humpback songs are transmitted also culturally, says Luke Rendell, a biologist at St andrews and co-author of the whale study,
"so here we have a population with two independently evolving cultural traditions a culture. David Wiley, research coordinator at the US National Oceanic and Atmospheric administration's Stellwagen Bank National Marine Sanctuary in Scituate,
"It adds to a growing body of information demonstrating the complexity of humpback-whale behaviour and its apparent roots in social learning,
Birds at live markets have been suspected as one source, but tens of thousands of tests in poultry and other animals elsewhere have failed so far to turn up significant levels of the virus. It is far from easy to devise effective ways to sample birds and animals for testing in a country with some 6 billion domestic birds
and 0. 5 billion pigs not to mention a vast population of wild birds, including many migratory species
. Although the risk factors for the spread of H7n9 are known not, voluminous research on its cousin,
the numbers of birds being transported, the distribution of live-bird markets and their supply routes, waterfowl numbers, land use and human population densities.
density in 2010), pigs (B), chickens (C) and ducks (D) in China and Asia in general.
Livestock densities are modelled numbers of animals per square kilometre standardized to 2006 national totals. Note different scale for pigs.
T. P. V. B. and M. G.,Universitã Libre de Bruxelles, Brussels.)The H7n9 virus has mutations that mean that it spreads from birds to humans more easily than does H5n1.
Proximity between bird and mammal populations could also give the virus opportunities for further adaptation to mammals,
An international team of researchers compiled maps for Nature showing the population densities of chickens, pigs, ducks and humans in many parts of China and throughout Asia.
47 million domestic ducks and 22 million pigs live within a 50-kilometre radius of each of the 60 H7n9 human cases that had occurred up to 16 april.
whether it represents a single imported case of animal-to-human transmission, an animal epidemic that has spread abroad,
Primate carriers Vietnam Airlines said on 19 april that it will no longer transport primates used in research experiments, effective from 1 may.
It was one of the last major carriers to transport primates for research: only Air france and Philippine Airlines say that they still do so.
Animal activism Animal-rights activists occupied an animal facility at the University of Milan in Italy on 20 april.
They demanded that all its 800 animals (mostly genetically modified mice) be transferred into their care.
After 12 hours of negotiations, the activists agreed to leave with fewer than 100 animals,
but mixed up some of the remaining animals and cage labels to disrupt experiments. Researchers say they have lost years of work.
The HSRC says that the iron was intended to fertilize phytoplankton, boosting ocean productivity and salmon populations.
Scientists, meanwhile, are vigorously debating whether the studies on neonicotinoids and the health of honeybees and bumblebees,
Neonicotinoids, which poison insects by binding to receptors in their nervous systems have been in use since the late 1990s.
protecting them from insect pests. But a growing body of research suggests that sublethal exposure to the pesticides in nectar
return to their hives and reproduce1-6 (see The buzz over bee health). The past year has seen a raft of papers about the effects of neonicotinoid pesticides on bees.
Honeybees in French fields exposed to thiamethoxam show impaired homing back to hives1. And bumblebee colonies exposed to"field-realistic levels of imidacloprid in labs show a decreased growth rate
and an 85%reduction in new queen production, compared with controls2. 21 october 2012:""Field-level exposure of bumblebees to imidacloprid and a non-neonicotinoid insecticide impairs foraging,
increases worker-bee mortality and reduces colony success3. 7 february 2013:""Prolonged exposure to imidacloprid and another insecticide impairs learning and memory in honeybees4.
27 march 2013: Lab study shows that imidacloprid, clothianidin and an organophosphate pesticide block firing of honeybee brain cells, especially when combined5.
March 2013:""No clear consistent relationships seen between neonicotinoid levels and colony mass or production of new queens by bumblebee hives6.
In January, the European Food safety Authority in Parma, Italy, Europe s food-chain risk-assessment body, concluded that three commonly used neonicotinoids clothianidin,
imidacloprid and thiamethoxam should not be used where they might end up in crops that attract bees, such as oilseed rape and maize.
they could play a part by making bees more susceptible to the parasitic mite Varroa destructor and the parasitic fungus Nosema apis,
Conducted by an agency within the UK Department for Environment, Food and Rural affairs (DEFRA), it exposed 20 Â bumblebee colonies at three sites to crops grown from untreated,
and harm to the insects. DEFRA also reviewed the body of evidence on neonicotinoids and concluded that,
a phenomenon that has been seen various rodents and people3-5. Inflammation brought on by abrupt weaning may also have a role,
even if it remains an infection that people catch from animals, says Marc Lipsitch, an epidemiologist at the Harvard School of Public health in Boston, Massachusetts.
We never saw this number of presumed avian/animal to human transmissions in such a short space of time.
and other birds has been reinforced by the new cases in Beijing and Henan province. These appeared out of the blue.
But with H7n9, it is only the appearance of new human cases that shows where the silent spread in birds
interim head of the UN Food and Agriculture Organisations's Emergency Prevention System for Transboundary Animal and Plant Pests and Diseases (EMPRES) in Rome.
Chinese authorities have identified already H7n9 in birds in live bird markets in Shanghai and other cities.
But despite intensive surveillance of poultry, wild birds, pigs and other animals, the animal reservoirs remain largely unknown.
That could mean that the main reservoir of virus in animals is restricted still to the Shanghai region.
or other animals over a far greater geographical area than thought. If so, new cases will keep popping up left right and centre.
and home to some 6 billion poultry as well as many migratory and other wild birds that may have a role in spreading the virus. On Wednesday,
Despite the difficulties of detecting H7n9 in poultry and birds, Martin remains optimistic that so long as the virus does not start to spread among humans the potential number of human cases can be curtailed by taking urgent tough measures such as keeping poultry flocks away from wild birds
and people and restructuring its live bird markets. Â It's too soon to say how big a threat H7n9 poses
because we don't know how many animals of which species have it, how genetically diverse it is,
or what the geographic extent is, says Lipsitch, It looks as though it will be at least as challenging as H5n1
They are testing wild birds and thousands of domestic fowl; analysing the viruses they find; and trying to trace people who have been exposed to infected patients.
some patients had contact with poultry or other animals just before falling ill, whereas others had Not late last week,
pigeons and ducks in live bird markets in Shanghai and Hangzhou making markets the leading suspected source.
Authorities have culled since tens of thousands of birds and closed down markets in Shanghai, Nanjing and Hangzhou.
The genetic sequences of the H7n9 viruses found in the birds are highly similar to those isolated from human patients,
including mammals, the pattern of many human cases over a wide area in a short time could be explained by live markets alone,
because birds from one or a few sources would be transported to multiple markets, says Malik Peiris, a flu virologist at the University of Hong kong.
WHO/ECDC/Xinhua state mediabut the various bird species found to be infected may not be the original source,
and wholesalers the birds came from, Peiris says, and test birds up through the supply chain.
Researchers know that H7 flu viruses mainly infect wild birds such as ducks, geese, waders and gulls,
and that they occasionally jump into poultry flocks. Kwok-Yung Yuen, an infectious-disease expert at the University of Hong kong, notes the proximity of the reported human cases to the Yangtze river delta
home to many wild birds, and to Chongming Island near Shanghai, a renowned site for watching migratory birds."
"It s likely wild ducks and geese that are carrying it, he suggests. But this H7n9 virus has not yet been detected in wild birds in the area."
"There is very little specific information on the source of this particular virus strain, its ecology or reservoir,
and it is premature to be hypothesizing on the vectors, says Taej Mundkur, who is flyways programme manager for conservation group Wetlands International in The netherlands.
He also co-convenes the Asia-Pacific Working group on Migratory Waterbirds and Avian influenza with the Food and agriculture organization of the united nations (FAO.
Unlike its cousin H5n1 which has killed millions of birds and several hundred people in Asia and elsewhere since 2003 H7n9 does not cause serious bird disease,
greatly complicating efforts to control it, says Vincent Martin, interim head of the FAO s Emergency Prevention System for Transboundary Animal and Plant Pests and Diseases (EMPRES) in Rome.
It would be next to impossible to detect H7n9 through routine surveillance for sick poultry among China s 6 Â billion domestic birds."
"This means stopping animal-to-human transmission is impossible, says Masato Tashiro, a virologist at the Influenza Virus Research center in Tokyo,
the World health organization s influenza reference and research centre in Japan. Each time the virus encounters new human hosts,
) A key component the haemagglutinin (H) protein on the surface of the virus already contains mutations known to shift its binding preference from bird cells to those of mammals.
it would imply that each person had picked separately up infections from birds. Only four sequences from four human cases are so far available,
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