Grackles have also been found dead in their hundreds recently in Arkansas, Louisiana and Kentucky. It appears that the birds died of blunt force trauma - possibly from being hit by a truck, wildlife biologist Bill Gates told local news station WAFF. He drew his conclusion from the feathers scattered across the snow, which was bloody in places. A collision with a big rig is also believed to be responsible for the deaths of over 100 birds whose bodies were found at the side of a California highway last weekend. One witness to that incident said it 'looked like they were committing suicide'.

The Alabama deaths are just the latest in a series of mass animal deaths around the world that have spurred conspiracy theories all over the internet. First, the blackbirds fell out of the sky on New Year's Eve in Arkansas. Then it was two million fish in the Chesapeake Bay, 150 tons of red tilapia in Vietnam, 40,000 crabs in Britain and other places across the world.

Blogs connected the deadly dots, joking about the 'aflockalypse' while others saw real signs of something sinister, either biblical or environmental. The reality, say biologists, is that these mass die-offs happen all the time and usually are unrelated. Federal records show they happen on average every other day somewhere in North America. Usually, we don't notice them and don't try to link them to each other.

Previous efforts in the 1990s to recover nuclei in cells from the skin and muscle tissue from mammoths found in the Siberian permafrost failed because they had been too badly damaged by the extreme cold. But a technique pioneered in 2008 by Dr Teruhiko Wakayama, of the Riken Centre for Developmental Biology, was successful in cloning a mouse from the cells of another mouse that had been frozen for 16 years.

Now that hurdle has been overcome, Akira Iritani, a professor at Kyoto University, is reactivating his campaign to resurrect the species that died out 5,000 years ago. "Now the technical problems have been overcome, all we need is a good sample of soft tissue from a frozen mammoth," he told The Daily Telegraph. He intends to use Dr Wakayama's technique to identify the nuclei of viable mammoth cells before extracting the healthy ones.

The nuclei will then be inserted into the egg cells of an African elephant, which will act as the surrogate mother for the mammoth. Professor Iritani said he estimates that another two years will be needed before the elephant can be impregnated, followed by the approximately 600-day gestation period. "I think we have a reasonable chance of success and a healthy mammoth could be born in four or five years," he said.

US weekly initial unemployment benefit claims showed their biggest increase in six months, suggesting that, even with recent signs of economic improvement, the labor market paints a gloomy picture for demand. The data helped drag down stock markets, even as Federal Reserve Chairman Ben Bernanke said he was hopeful about the recent improvement in the outlook, saying he now expects the economy to expand between 3 percent and 4 percent this year.

A delegate from a Gulf OPEC member state said OPEC will only hold an emergency meeting if oil climbs above $100 and stays there, although the group's Gulf members could informally add supply if needed. "OPEC will only have an extraordinary meeting if oil prices exceed $100 and stay there. We don't want the market to panic," the delegate told Reuters.

The prospect of oil breaking $100 a barrel, last touched in October 2008 after Lehman Brothers collapsed, has raised alarm bells about the impact of fuel costs on the economic recovery. Top exporter Saudi Arabia has said it favors an oil price between $70 to $80 a barrel, but Libya's top oil official on Thursday said oil prices at $100 a barrel would not harm the world economy and there is no need for OPEC to hold an emergency meeting or add supplies.

Police say the number of dead is likely to rise further. Rescuers have been trying to find survivors in remote areas. Relatives have been joining in the search but often only finding bodies of loved ones. The death toll has now surpassed that of mudslides in Caraguatatuba in Sao Paulo state in 1967 in which up to 430 people died.

The Brazilian armed forces have brought in a field hospital and hundreds of people have taken refuge in the gymnasium in Teresopolis. But the number of injured was threatening to overwhelm the medical services. Jorge Mario, the mayor of the Teresopolis, said: "There are three or four neighbourhoods that were totally destroyed in rural areas. There are hardly any houses standing there and all the roads and bridges are destroyed."

President Rousseff described the destruction as an act of God but she also expressed anger at illegal construction. "We saw areas in which mountains untouched by men dissolved. But we also saw areas in which illegal occupation caused damage to the health and lives of people. Saying that building houses in risky areas was "the rule rather than the exception", in Brazil she added: "When there are no housing policies in place, where will a person with an income of up to two minimum wages live? He will live where he is not allowed to."

Rio de Janeiro Governor Sergio Cabral blamed local governments for allowing poor building and illegal occupations. "Unfortunately, what we saw in Petropolis, Teresopolis and Nova Friburgo, since the 1980s, was a problem similar to what happened in the city of Rio - letting the poorer people occupy risk areas."

The number of foreclosure filings, which includes default notices, auctions and repossessions, was a record 2.9 million last year, including 257,747 filings in December. "Total properties receiving foreclosure filings would have easily exceeded 3 million in 2010 had it not been for the fourth-quarter drop in foreclosure activity - triggered primarily by the continuing controversy surrounding foreclosure documentation and procedures that prompted many major lenders to temporarily halt some foreclosure proceedings," said James J Saccacio, chief executive officer of RealtyTrac.

"Even so, 2010 foreclosure activity still hit a record high for our report, and many of the foreclosure proceedings that were stopped in late 2010, which we estimate may be as high as a quarter million, will likely be re-started and add to the numbers in early 2011," Saccacio said. The firm said Nevada, Arizona and Florida continued to post the highest foreclosure rates in the country.

And just five states - California, Florida, Arizona, Illinois and Michigan - accounted for more than half of all foreclosure activity. One in every 11 housing units in Nevada received at least one foreclosure filing in 2010, more than four times the national average. In 2005, before the housing bust, banks took over just about 100,000 houses, according to the Irvine, California-based company.

Etna is Europe's tallest and most active volcano and has seen increased activity in recent months yet its seismic might poses no immediate threat to the nearby towns and cities. According to the Italian Institute of Geophysics and Volcanology, a slight increase in Etna's volcanic tremors had been recorded on Tuesday, reaching its peak at 7am local time yesterday.

The activity diminished but at 9:30pm local time on Wednesday night, Etna roared into life sending lava spewing down its sides. The volcano has been active for around half a million years, with 15,000 people killed during its most violent eruption in 1669.

Thousands of air passengers were today facing hours of delays after blizzards battered 49 of America's 50 states. At least 90,000 people were caught up in the chaos at airports across the States with as many as 4,500 flights cancelled.

But millions of New Yorkers were able to struggle to work after an army of emergency workers with plows and salt spreaders were out in force early to clear the city's roads.

Families minister Maria Miller described the scale of family breakdown as a 'tragedy', saying urgent reforms are needed to ensure children maintain relationships with both parents. The Government will today unveil the biggest overhaul of child maintenance for more than a decade.

Mrs Miller said: 'We know that if effective financial arrangements are in place, those parents are much more likely to stay in contact and much more likely to have a strong relationship with their children. Staying in contact with both parents is absolutely critical to give a child the best start in life.'

Mrs Miller, in an interview with the Daily Mail, said the latest figures showed that there were 3.5 million children from broken homes. Almost half have no effective maintenance arrangements. 'Twenty per cent of children from separated families lose contact with the non-resident parent within just three years,' Mrs Miller said.

This will push the cost of unleaded petrol up to 1.36 a litre (6.18 pounds a gallon) and diesel up to 1.40 a litre (6.36 pounds a gallon). It means the cost of filling a saloon with a 50-litre tank will soar to about 70 pounds. Only 12 months ago, when petrol was 1.10 a litre, it would have been 56 pounds, marking a rise of 25 per cent.

The gloomy forecast for drivers came as Brent crude oil rose to $98 a barrel on London markets yesterday for the first time in 27 months. Experts said breaking the $100 a barrel threshold is 'imminent' amid growing global demand.

Petrol retailers have written to George Osborne urging the Chancellor to abandon the next automatic 'escalator' rise in fuel duty in his Budget, which will see up to 5p a litre added to the cost of fuel. Combined with predicted oil price increases, motorists and hauliers face a total rise of 8p. The Federation of Small Businesses warned that its members were being 'hard-hit at the most fragile of times' as they struggle in the economic downturn.

Jose Barroso, head of the European Commission, called on EU leaders to boost the firepower of the EU's 440 billion euros (366 billion pounds) bail-out fund and beef up its role, allowing it to intervene with pre-emptive bond purchases to help states under threat. "It is important for the markets to know that Eurozone leaders are committed to do whatever is necessary," he said, hoping for action as soon as early February.

He also proposed a "new phase of European integration" with far-reaching oversight of the budgets, pensions, labour markets, and trade flows of EU states to prevent a recurrence of the imbalances that led to the EMU debt crisis. Mr Barroso said the fund boost was a "precautionary" move, not directed at any one country. The gambit is risky since it may be taken by investors as a sign that Brussels fears imminent contagion to Spain, deemed too big for the current fund.

The response in Paris and Berlin was chilly. "We think the fund is big enough," said Francois Baroin, France's budget minister. German Chancellor Angela Merkel said the bail-out mechanism was "nowhere near exhaustion", adding curtly that she did not wish to debate the matter "any further".

The United States fears that the risk of war is rising between US ally South Korea and the heavily militarized and increasingly unpredictable regime in North Korea, which the Pentagon also considers a looming threat to the mainland United States.

"It's a long-standing principle that every country has the right to protect itself and defend itself against an unprovoked attack," Gates said following discussions with Japanese political leaders keyed to the rising threat of war on the Korean peninsula.

Earlier this week Gates lobbied China to pressure the North not to go too far. Gates will go to South Korea on Friday for a quick and hastily arranged crisis session about the North. Gates was urging patience while China, which props up the fellow communist state, tries to persuade North Korea to avoid a military provocation that South Korea would feel bound to answer.

US government data showing US crude stocks falling for a sixth straight week helped extend this week's gains. Disruptions from Alaska and Norway stoked supply concerns and cold weather in the US Northeast fed demand for heating oil.

Oil's climb back toward $100 a barrel - last touched in October 2008 - has raised concerns about the impact of higher fuel costs on the tenuous economic recovery. "Back in 2008, (US) crude oil only traded above $100 a barrel for about six months before the world economy collapsed into the worst crisis since the 1930s," warned Sabine Schels, commodity strategist for Merrill Lynch.

Crude's rise on Wednesday was part of wider gains across commodities, with metals rising and soybean and corn futures touching 30-month highs that further stoked economic worries.

While officials are drawing comfort from stable rice prices, key for feeding Asia, they warn that a sustained period of high prices, especially in grains such as wheat, would hit poorer countries. Food price hikes have already led to riots in Algeria and Mozambique.

"Stocks of corn and soyabean are at incredibly tight levels... and the markets are surging to incredibly strong prices," Chad Hart, agricultural economist at Iowa State University, said. Dan Basse, president of AgResource, a Chicago-based forecaster, added: "There's just no room for error any more. With any kind of weather problem in the upcoming growing season we will make new all-time highs in corn and soy, and to a lesser degree wheat futures."

Agricultural traders and analysts warn that the latest revision to US and global stocks means there is no further room for weather problems. The crops in Argentina and Brazil, to be harvested soon, look fragile due to dryness.

Traders are particularly concerned about the cost of vegetable oil, key for developing countries such as China where an emerging middle class is buying more frying oil. The US Department of Agriculture said the ratio of global stocks-to-demand would fall later this year to "levels unseen since the mid-1970s, reflecting an accelerated pace of vegetable oil" consumption for food and fuel.

At least three firefighters were among 107 people killed in mudslides in Nova Friburgo. Brazil has seen severe flooding this year, leaving thousands homeless. The death toll has been steadily climbing as rescuers reached remote villages in the mountains, some of which have been destroyed.

A state of emergency has been declared in Teresopolis, 100km (62 miles) north of Rio Janeiro, where more than 1,000 people have been left homeless. Another 20 people died in the nearby town of Petropolis. With many people still reported missing it is feared the death toll could rise even further and there is concern about water-borne diseases.

Earlier this week, torrential rains in neighbouring Sao Paulo state left 13 people dead and brought traffic chaos to Brazil's biggest city. In Teresopolis, a river burst its banks, submerging buildings, while the rainfall set off several mudslides. "It's a huge catastrophe, a major disaster," Teresopolis Mayor Jorge Mario told Globo television. TV footage showed homes destroyed and cars submerged

The 50-page analysis of 37 global risks precedes the World Economic Forum's (WEF) annual meeting in two weeks' time in the Swiss ski resort of Davos, which brings together high-level politicians, central bankers and business leaders. "The world is probably more vulnerable to future shocks than it ever has been in the last half century," WEF Chief Business Officer Robert Greenhill told reporters at a briefing in London.

"The response to the financial crisis has drained national treasuries and drained household incomes, but the underlying risks still remain." Debt was also highlighted as a top threat in the WEF report last year, and Greece's meltdown went on to overshadow the 2010 Davos meeting. Since last January, the euro zone's crisis has spread to Ireland, which has also been bailed out, and now threatens to engulf Portugal and possibly Spain - the euro zone's fourth largest economy - as investors worry about governments' ability to repay debts and the risk of write-downs for bondholders.

There will also be a greater focus than ever in Davos on the mismatch between buoyant economic growth in emerging markets and sluggish conditions in the developed world. Such imbalances increase the risk of protectionism and currency wars as 'hot' capital surges into emerging economies.

Other threats in 2011 include tightening supplies of basic resources such as food, water and energy, which John Drzik, chief executive of management consultancy Oliver Wyman, said were aggravated by lack of investment in infrastructure because of chronic fiscal deficits.

Surging global food prices have already set warning lights flashing on inflation. Food prices hit a record high last month, according to the United Nations food agency, surpassing levels in 2008 that sparked riots in countries from Egypt to Haiti. "We're entering a new age of commodity price volatility," Drzik said. "It is not just a near term issue."