MIAMI — From “Scarface” to “Miami Vice,” Florida’s drug problem has been portrayed as the story of a single narcotic: cocaine. But for Floridians, prescription drugs are increasingly a far more lethal habit.

An analysis of autopsies in 2007 released this week by the Florida Medical Examiners Commission found that the rate of deaths caused by prescription drugs was three times the rate of deaths caused by all illicit drugs combined.

Law enforcement officials said that the shift toward prescription-drug abuse, which began here about eight years ago, showed no sign of letting up and that the state must do more to control it.

“You have health care providers involved, you have doctor shoppers, and then there are crimes like robbing drug shipments,” said Jeff Beasley, a drug intelligence inspector for the Florida Department of Law Enforcement, which co-sponsored the study. “There is a multitude of ways to get these drugs, and that’s what makes things complicated.”

The report’s findings track with similar studies by the federal Drug Enforcement Administration, which has found that roughly seven million Americans are abusing prescription drugs. If accurate, that would be an increase of 80 percent in six years and more than the total abusing cocaine, heroin, hallucinogens, Ecstasy and inhalants.

The Florida report analyzed 168,900 deaths statewide. Cocaine, heroin and all methamphetamines caused 989 deaths, it found, while legal opioids — strong painkillers in brand-name drugs like Vicodin and OxyContin — caused 2,328.

Drugs with benzodiazepine, mainly depressants like Valium and Xanax, led to 743 deaths. Alcohol was the most commonly occurring drug, appearing in the bodies of 4,179 of the dead and judged the cause of death of 466 — fewer than cocaine (843) but more than methamphetamine (25) and marijuana (0).

The study also found that while the number of people who died with heroin in their bodies increased 14 percent in 2007, to 110, deaths related to the opioid oxycodone increased 36 percent, to 1,253.

Florida scrutinizes drug-related deaths more closely than do other states, and so there is little basis for comparison with them.

It has also witnessed several highly publicized cases in recent years that have highlighted the problem. Only last year, an accidental prescription drug overdose killed Anna Nicole Smith in Broward County.

Still, the state has lagged in enforcement. Thirty-eight other states have approved prescription drug monitoring programs that track sales. Florida lawmakers have repeatedly considered similar legislation, but privacy concerns have kept it from passing.

As a result, federal, state and local law enforcement officials say, Florida has become a source of prescription drugs that are illegally sold across the country.

“The monitoring plan is our priority effort, but that is not enough,” William H. Janes, the Florida director of drug control, said in a statement accompanying the study. He said Florida was also looking at ways to curb illegal Internet sales and to encourage doctors and pharmacists to identify potential abusers.

Some local police departments have taken a more novel approach.

In Broward County on May 31, deputies completed a “drug takeback” in which $5 Wal-Mart, CVS or Walgreens gift cards were distributed to 150 people who cleaned out their medicine cabinets and turned in unused drugs in an effort to keep them out of young people’s hands.

“The abuse has reached epidemic proportions,” said Lisa McElhaney, a sergeant in the pharmaceutical drug diversion unit of the Broward County Sheriff’s Office. “It’s just explosive.”

Saudi Arabia, the world’s biggest oil exporter, is planning to increase its output next month by about a half-million barrels a day, according to analysts and oil traders who have been briefed by Saudi officials.

The increase could bring Saudi output to a production level of 10 million barrels a day, which, if sustained, would be the kingdom’s highest ever. The move was seen as a sign that the Saudis are becoming increasingly nervous about both the political and economic effect of high oil prices. In recent weeks, soaring fuel costs have incited demonstrations and protests from Italy to Indonesia.

Saudi Arabia is currently pumping 9.45 million barrels a day, which is an increase of about 300,000 barrels from last month.

While they are reaping record profits, the Saudis are concerned that today’s record prices might eventually damp economic growth and lead to lower oil demand, as is already happening in the United States and other developed countries. The current prices are also making alternative fuels more viable, threatening the long-term prospects of the oil-based economy.

President Bush visited Saudi Arabia twice this year, pleading with King Abdullah to step up production. While the Saudis resisted the calls then, arguing that the markets were well supplied, they seem to have since concluded that they needed to disrupt the momentum that has been building in commodity markets, sending prices higher.

The Saudi plans were disclosed in interviews with several oil traders and analysts who said that Saudi oil officials had privately conveyed their production plans recently to some traders and companies in the United States. The analysts declined to be identified so as not to be cut off from future information from the Saudis.

Last week, King Abdullah also took the unprecedented step of arranging on short notice a major gathering of oil producers and consumers to address the causes of the price rally. The meeting will be held on June 22 in the Red Sea town of Jeddah.

Oil prices have gained 40 percent this year, rising to nearly $140 a barrel in recent days and driving gasoline costs above $4 a gallon. Some analysts have predicted that prices could reach $200 a barrel this year as oil consumption continues to rise rapidly while supplies lag.

The growing volatility of the markets, including a record one-day gain of $10.75 a barrel last week, has persuaded the Saudis that they need to step in, analysts said.

Tony Fratto, a White House spokesman, said, “We would welcome any and all increases in oil production, including from Saudi Arabia.”

But the measure carries some risks to the kingdom and is not guaranteed to bring down prices, analysts said. Some investors doubt that Saudi Arabia has the capacity to increase its production beyond its current levels.

“This clearly represents the biggest test for them,” said John Kilduff, a senior vice president at the brokerage firm MF Global, who said the move could backfire if investors failed to respond to the extra Saudi supplies. No other producer has the capacity to quickly expand production.

Oil prices fell on Friday, slipping $1.88 to settle at $134.86 a barrel on the New York Mercantile Exchange, after reports of the prospective Saudi increase trickled into the market.

Ibrahim al-Muhanna, an adviser at the Saudi petroleum ministry, declined to comment on the production increase but said that Saudi Arabia was uncomfortable with oil prices. “Our goal is to bring back stability to the oil market,” he said.

Consumers are complaining that rising fuel prices are imposing a growing toll on their economies, and contributing to higher food costs. The Australian prime minister, Kevin Rudd, said this month that it was time “to apply the blowtorch to the OPEC organization.”

In Washington, bipartisan support is also growing to pass a law allowing the Justice Department to engage in antitrust proceedings against OPEC producers accused of curbing supplies to drive up prices.

Pressure is also mounting in consuming countries to address record energy prices. Congress is debating measures that would tackle speculators, whom many in Washington blame for driving up commodity prices.

When the Organization of the Petroleum Exporting Countries, of which Saudi Arabia is the most powerful member, met in March, it decided against increasing production, blaming speculators and a declining dollar, not a shortfall in supplies, for driving up oil prices.

Saudi Arabia’s unilateral policy could put it at odds with other members of the OPEC cartel. In a report from the group’s secretariat on Friday, OPEC analysts said they saw no need to put more oil on the market. “Claims that the recent surge in prices is due to a supply shortage are unjustified,” the report said.

Saudi Arabia is completing a huge expansion program in its oil industry that is expected to bring its production capacity to 12.5 million barrels a day by 2009. As part of that expansion, Saudi Aramco, the country’s national oil company, is planning to start soon an oil field, called Khursaniyah, with a daily production rate of 500,000 barrels.

The production increase, which would amount to less than 1 percent of global consumption, could be made public next week at the energy meeting, which is expected to bring together a large number of consuming and producing countries, including the United States, Russia, Britain, China, India and Japan.

While the meeting is not expected to achieve anything tangible, Saudi officials hope that tackling the issue publicly will break the upward momentum that is dominating oil markets.

“They’ve created pressure on themselves to make a concrete move at this meeting,” said Adam Robinson, an analyst at Lehman Brothers. “But when the king calls an oil summit, the markets would do well to take heed.”

THE success of Silvio Berlusconi's hair transplant, four years ago, relied on the fact that the septuagenarian prime minister had enough of a thatch on the back of his head to enable some of it to be transferred to his thinning top. Although hair transplants have advanced to the stage where they are virtually undetectable (no more plugs of hair), they still rely on moving hairs from one place to another. So, though hairlines such as Mr Berlusconi's can be thickened up, or even straightened, there may well not be enough material available to lower a hairline to its former, youthful level.

AP

La bella figura

Finite supply remains the main drawback of this sort of transplant surgery. The most common form of hair loss in men is “male pattern baldness”, characterised by a receding hairline and the thinning of the hair on the crown. It is caused by hormones and mediated by genetic predisposition. Hair transplants work because the hairs at the back of a man's head are not vulnerable to hormonal attack, and will thus grow quite contentedly in their new home—assuming there are enough of them to transplant.

For those so follicularly challenged that they have little hair to move around in this way, however, there is now hope. This comes not in a jar, but in a test-tube from a Manchester-based company called Intercytex. The firm's technique exploits the regenerative properties of what are known as dermal papilla cells. These are the cells that create hair follicles in the first place. They remain at the base of the hair when they have finished their job.

Some years ago it was discovered that when these cells are relocated, an entirely new hair will grow. That observation is only useful, though, if you can multiply dermal papilla cells—and do so in a way that allows them to keep their ability to induce hair growth. For, in normal culture, dermal papilla cells quickly lose this sought-after ability.

This, says Nick Higgins, Intercytex's boss, has taxed scientists for years. Intercytex appears to be working on two solutions. Although it is understandably tight-lipped about the exact mechanism behind its success, one probably enlists the help of cells called keratinocytes, which interact naturally with the dermal papilla cells of the hair follicle and secrete a chemical factor that supports their growth. At present, the identity of this growth factor is a mystery. However, it is likely that one of Intercytex's methods involves supplying this factor to cultured dermal papilla cells. Intercytex's second approach seems to involve culturing the dermal papilla cells with proteins that take part in signalling during the process that creates hair.

The long and short of it is that being able to multiply these cells while preserving their efficacy opens the way for unlimited supplies of head hair. Intercytex is therefore conducting a trial of the technology in Manchester. Nineteen “patients” have had a small amount of hair removed, follicles and all, from the backs of their heads. Their dermal papilla cells have been extracted, multiplied and re-injected into their scalps. The trial's full results will not be available until March 2009, but the company has already said that at least two-thirds of its patients have generated new hair within six months.

Unfortunately for eager baldies, regulations require more trials. As a result it is likely to be five years before any product is on the market. Nor will Intercytex's technique do anything about that other bane of ageing, the tendency of hair to go grey. For the time being, even Mr Berlusconi will have to continue to dye his locks.

“DESPERATE,” wailed Giovanni Bisignani, summing up the plight of the air-transport industry. Speaking at the industry's annual bash in Istanbul, the director-general of IATA, its trade body, lamented that 24 airlines had gone bust since January. Airlines are squeezed between high oil prices and falling passenger demand in America and Europe. He predicted that if the oil price does not fall, airlines will swing from a combined profit of $5.6 billion in 2007 to a loss of $6.1 billion.

Many airline executives fear that after the cost-cutting that swept through the industry in the wake of September 11th 2001, they no longer have any fat left to trim. The speck of comfort for some is the hint that the predicament of the budget airlines could be worse still. A fortnight ago Willie Walsh, the boss of British Airways (BA), said he believed that “the era of very low fares is behind us...the industry has no future if it doesn't price in its costs.” Already, big airlines are following the lead of the low-cost airlines and levying what have euphemistically become known as “ancillary” charges. These include making passengers pay extra for luggage that has to go in the hold, and for in-flight meals.

Mr Walsh and others like him believe that the inevitable increases in fares and the imposition of fuel surcharges will hurt the budget airlines most, because their brands are synonymous with “give-away” seat prices. That, in turn, they argue, will strike at a vital part of the no-frills business model—the kind of cheap, discretionary short breaks that people either choose at the last minute or because they have taken advantage of a tempting special offer.

It is an analysis that may prove half-right and half-wrong. Among the weaker low-cost carriers, most of which are already losing money, the latest turn of the screw could prove to be fatal. But it would be a big mistake to conclude the same about either of Europe's dominant budget airlines, Ryanair and easyJet, with their strong balance sheets, modern fleets and strong cultures of low-cost operation.

Ryanair's combative boss, Michael O'Leary, seems almost to welcome Mr Bisignani's Jeremiad. Announcing a 20% increase in full-year profits to €481m ($680m) on June 3rd, he admitted that if oil prices do not fall, his airline will merely break even in this financial year. But his message was still bullish. “A downturn in the industry is badly needed,” he said. “The great thing about oil at $130 a barrel is that you will hear less of this environmental guff about taxing air travel, and it will see off a lot of the inefficiency in the system.” He not only expects some airlines to disappear, but he believes that the likes of BA, “which is levying surcharges faster than it's losing bags at Terminal Five”, will end up handing more business to Ryanair.

Geoff van Klaveren, an airline analyst at Exane BNP Paribas, calculates that BA's £6 ($12) fuel surcharge on short-haul flights would be worth an 8% yield increase for Ryanair and 6% for easyJet. With healthy advanced bookings, he expects pricing for both airlines to be “very strong” this summer. EasyJet's boss, Andy Harrison, is quieter than Mr O'Leary, but actions can speak louder than words. At the end of May he bought nearly £500,000 ($1m) of shares in his company.

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HOW reliable are the Brazilian government's estimates of deforestation? Not at all, according to Blairo Maggi, the governor of Mato Grosso state. He says his officials have visited areas officially identified as newly deforested to find that clearance happened long ago. Some scientists agree that the satellite images are not detailed enough to show what is really going on.

The National Institute for Space Research has two programmes that measure deforestation. The first, called PRODES, relies mainly on Landsat, an American satellite which provides colour images of great detail (each pixel represents 30 metres on the ground). But the forest is often obscured by cloud. So PRODES also draws on images from other satellites such as CBERS-2, a joint project between Brazil and China, to get an uninterrupted view of what is going on. The end result is a map made up of 213 separate images. Sorting through each image takes a good computer a whole day, so the institute also uses human interpreters. The results are released at the end of each year. In the past three years, PRODES has shown deforestation slowing (see chart).

The second programme is called DETER, an acronym that means “to detain” in Portuguese. It produces data every 15 days, using images from Terra, another American satellite. Terra's field of vision is over 2,000km wide, allowing it to cover the world in two days. This omniscience comes at a price: its resolution is only 250 metres, so it does not pick up smaller clearings.

DETER started in 2004 as a way to spot deforestation while it happens. Its results go straight to the branch of the environment ministry whose job is to prevent it. The institute uses these images to estimate total forest clearance, which is where the controversial monthly numbers come from. These monthly reports are more useful as a guide to the trend than as absolute numbers, according to Dalton Valeriano, who oversees both programmes at the institute's headquarters at São José dos Campos, near São Paulo.

DETER predicted the slowing rate of deforestation that PRODES duly reported in each of the past three years. With the monthly numbers now rising, the more accurate annual measure is likely to concur when it is revealed in December.

Reuters

Beefing about beef

THERE was little to celebrate as South Korea's president, Lee Myung-bak, marked his hundredth day in office this week. The president's approval rating is 21%, a fall of 31 points since his inauguration, according to Gallup, a pollster. Month-long protests against a decision to resume imports of American beef have grown in size and intensity. Many of the tens of thousands of people who gather nightly outside Seoul's City Hall call for Mr Lee's resignation.

The president's aides and his own right-wing Grand National Party confess they are worried about rising public discontent. Dong A, a conservative newspaper, marked Mr Lee's 100 days in office with a picture of summer storm-clouds louring over the Blue House, the office and residence of the president.

Mr Lee has only himself to blame for his abrupt fall from grace. Since his landslide victory in December, he has adopted an imperial style of leadership reminiscent of his days as chief executive of various arms of Hyundai, a conglomerate. Ignoring calls from many in South Korea for a more conciliatory style, he has pushed a controversial scheme to construct a system of canals. He has alienated civil servants by publicly berating them and threatening to cull their numbers in the interests of efficiency. And he has told state-run corporations they will be privatised, replacing many of their bosses with his loyalists.

In an effort to repair frayed ties with America, Mr Lee agreed in April to lift a ban on imports of American beef, which were suspended in 2003 after the discovery of mad-cow disease among cattle. South Koreans reacted furiously to the move. Housewives, pensioners, businessmen and students took to the streets in protest. Mr Lee was initially dismissive. His police chief warned protesters they needed a permit and would be arrested. That served only to fuel public anger.

This week a contrite Mr Lee said he would listen to the public's concerns. The Blue House has dropped hints of a cabinet shuffle. Among those expected to be replaced is the agriculture minister. Even Mr Lee's own party wants his decision-making to become more transparent. But none of South Korea's political parties seems to be trusted by a public concerned about rising prices and the uncertain economic outlook. The main opposition United Democratic Party has yet to recover electoral support after suffering devastating losses in April's parliamentary elections. Even a UDP spokesman puts the party's approval rating at less than 20%.

Meanwhile America is expressing frustration at what it sees as its ally's unfounded fear of its beef. This week South Korea's government said it wanted to renegotiate the beef-import agreement. A Gallup poll found that 81% of Koreans support for this. But Mr Lee has much else to do to reclaim confidence in his leadership, and dispel the clouds gathering over the Blue House.

Illustration by David Simonds

“IT WOULD only take half an hour for the French boats and French helicopters to reach the disaster area.” Those were the wistful words uttered by Bernard Kouchner, France's foreign minister, as his country's diplomats at the United Nations vainly argued that aid might have to be “imposed” on Myanmar if the military regime refused to co-operate.

Even as he spoke, diplomats from China, Vietnam, South Africa and Russia were mocking his idea that the “responsibility to protect” (a new concept in global affairs, implying that saving human lives might in some extreme circumstances override sovereignty) could be invoked in the case of Myanmar's cyclone. China noted acidly that the idea had not been cited in 2003 when France suffered a deadly heatwave.

David Miliband, Britain's foreign secretary, reignited the debate on May 13th. Challenged by a radio interviewer to say whether the new concept (designed to deal with crimes like genocide or ethnic cleansing) could also apply to natural disasters, he replied: “It certainly could, and we have been absolutely clear...that all instruments of the UN should be available.” But nobody expects Britain, France or any other country to fight its way into Myanmar. As Mr Miliband observed, “the regime has 400,000 troops in uniform.” For ordinary people, unfamiliar with the UN's arcane workings, it looks rather depressing. Will there ever be a good moment to cite the notion of a responsibility to protect—unanimously adopted by more than 150 states at the UN World Summit in 2005—as Mr Kouchner is now suggesting?

The tortuous development of that concept is a tale close to the French minister's heart. As a young doctor, he saw the horrors of the Biafran famine triggered by Nigeria's civil war. Soon afterwards he co-founded Médecins Sans Frontières (Doctors Without Borders) and became a leading supporter of the “right of humanitarian intervention” in cases where governments fail their own people.

What Mr Kouchner was proposing sounded, in its stronger versions, like a revolution in global affairs—overturning the 1648 treaty of Westphalia, which upheld the right of sovereign states to act freely within their own borders. The UN Charter of 1945 also upholds the Westphalia principles, by stating in article 2(7), that “nothing should authorise intervention in matters essentially within the domestic jurisdiction of any state.” But Chapter VII does entitle the Security Council to take action in cases of a “threat to the peace, breach of the peace or act of aggression”.

Tension between those two principles—sovereignty versus intervention—has been palpable for decades. Some countries stress the enforcement powers laid down by Chapter VII. Others (mostly in the poor world) insist that state sovereignty always trumps, even in humanitarian emergencies.

In practice, since the end of the cold war the UN has been intervening more often in conflicts within (as opposed to between) states. Sometimes it has happened with, and sometimes without, the consent of the governments concerned.

In 1999 Tony Blair became the first world leader to assert a moral right to “get actively involved in other people's conflicts”—even without leave from the Security Council—if it was the only way to stop dire suffering. Speaking in Chicago after NATO's war over Kosovo, which the Security Council had declined to endorse, Britain's then prime minister made the case for “just war, based not on territorial ambitions, but on values”.

Four years later, an American-led coalition invaded Iraq, using somewhat similar rhetoric about the need to overthrow a dangerous tyrant for the good of everyone. Although it wasn't in any formal or legal sense a test case for responsibility to protect, many people felt that the disastrous outcome in Iraq discredited the entire idea of intervention for “altruistic” purposes.

Meanwhile, Canada had set up an International Commission on Intervention and State Sovereignty, under the chairmanship of Gareth Evans, a former Australian foreign minister, and Mohamed Sahnoun, a former Algerian diplomat. In their report, published in 2001, it was they who first suggested changing the discretionary “right to intervene” into a more muscular “responsibility to protect”, or R2P as it is known in diplomatic jargon. Under it, the “international community” (in effect the UN) would be placed under an actual obligation to take, if necessary, coercive action to protect people at risk of grave harm, in accordance with clear criteria.

Taken up by a High-Level Panel on UN reform in 2004 and adopted by Kofi Annan, then UN secretary-general, the principle survived the haggling in the run-up to the 2005 World Summit to squeeze its way into the final “Outcome Document”, though shorn of criteria. But it was never intended to cope with the aftermath of natural disasters or even “ordinary” human-rights violations. It was to be invoked only for genocide, war crimes, ethnic cleansing or crimes against humanity.

From the start, the idea was viewed by the developing world as a trick by the West to impose its values. Cuba, Egypt, Russia, Algeria and Myanmar have been vocal opponents. They have been leading a determined effort to obstruct the formal appointment of Edward Luck, a professor at Columbia University, as a special UN adviser on the issue. He still has no salary, no real title and no UN office.

Others, this time in the West, are asking whether responsibility to protect will ever be more than an empty slogan. When it came to it, who would be willing to intervene? How could such action ever get past all five of the Security Council's veto-wielding powers? Besides, as a senior UN official laments, the Iraq fiasco has “poisoned this well”. It showed that an armed intervention, even if its declared aims are benign, can set off a whole chain of terrible consequences.

“It never takes much more than a few days around the corridors and meeting rooms of the UN in New York to have your latest dose of optimism beaten out of you,” Mr Evans moaned recently. But he and other proponents of responsibility to protect have started to fight back, seeking to correct “misconceptions” over the concept. It's not meant to be a grand new doctrine or policy, they insist, rather a modest “strategy” for protecting the defenceless.

It is not only about military intervention, they add, but also prevention: spotting situations that could result in mass atrocities. Political, diplomatic, legal and economic measures should be tried before any resort to arms. Not every conflict, potential conflict, or gross abuse of rights should prompt application of the rule—only the worst cases. And even when all non-military means have failed, armed intervention may still not be the right answer. The consequences must be weighed to ensure that it will not do more harm than good to the people it seeks to protect.

Responsibility to protect is not yet dead, but it is fragile. Supporters point to the power-sharing deal that stopped Kenya's civil war in February as the concept's first success. The fact that the UN, in principle, retains the right to impose its will by force may have made it easier for the world body to broker a settlement.

Perhaps. But the idea will need some clearer successes than that if it is going to survive. And Myanmar, apparently, is not going to be one of them.

AP

NEW life generally flourishes in the spring, unless it is marine life in the Gulf of Mexico. Every spring the coastal waters turn into a scene of devastation and death. Known as a “dead zone”, this vast oxygen-depleted area extends along the coast between Louisiana and Texas.

Hundreds of the world's coastal regions have dead zones. They mostly occur when spring rainfall gathers on land, makes its way into streams and rivers, and eventually tumbles down to the ocean. The rivers carry with them a cargo of nutrients, in particular nitrogen, from farms in the watershed. When this nitrogen reaches the sea it causes a brief frenzy of algal growth which depletes the water of oxygen. Fish, clams, shrimp, crabs, entire mussel reefs and other bottom-dwelling animals can be wiped out.

Jane Lubchenco, a marine ecologist from Oregon State University, says this nutrient run-off from land is increasing the number, size, duration and severity of the dead zones. This is mainly because the use of fertilisers in agriculture is increasing. Sometimes the waste from animals or human sewage worsens the blight.

Nitrogen, which, makes up about 78% of the Earth's atmosphere, is an inert gas but it has more reactive forms. One of these comes from making fertilisers, using the Haber-Bosch process which converts nitrogen gas into ammonia. Although some of the fertiliser used on fields is taken up by plants and then by the animals that eat them, most of it accumulates in the soil before being washed to the coast and eventually even to the deep ocean. Another source of nitrogen pollution comes from fossil fuels, which produce nitrogen oxides when they are burnt. These oxides are released into the atmosphere and they can fall back to earth as acid rain.

The release of reactive nitrogen into the environment has a “cascade” effect, according to two papers published in the latest issue of Science. James Galloway of the University of Virginia, the lead author of one of the papers, says that every single atom of reactive nitrogen can cause a cascading sequence of events which can harm human health and ecosystems.

In the lower atmosphere the oxides of nitrogen add to an increase in ozone and small particles, which can cause respiratory ailments. The reactive nitrogen in acid rain kills insects and fish in rivers and lakes. And when it is carried to the coast it contributes to the formation of dead zones and in the creation of red tides (a kind of toxic, algal bloom that can form in the sea). It is then converted to nitrous oxide which adds to global warming.

According to Alan Townsend, of the University of Colorado, Boulder, humans are creating reactive nitrogen at a record pace, and moving it around the world as never before. People create about 190m tonnes of reactive nitrogen a year, compared with 90m-120m tonnes from natural processes, such as nitrogen-fixing bacteria and lightning strikes.

Some of this man-made nitrogen helps to grow food and biofuels, but the nitrogen uptake by plants and animals is so inefficient that only 10-15% of the reactive nitrogen created for food production actually ends up being eaten as food. The rest of the nitrogen goes into the environment. What is worrying is that the production of reactive nitrogen is set to increase according to most predictions.

Doug Capone, of the University of Southern California, says that the increased levels of reactive nitrogen are now responsible for about 3% of the biological production of new marine life in the open ocean. Because there is only a limited supply of nitrogen out in the open ocean, additional amounts of it can have a huge stimulating effect.

This sounds like it is good news for the climate, because marine life absorbs about 10% of man-made carbon dioxide into the ocean. The more marine life there is, the more absorption. But two-thirds of this effect may be offset by the greater release of nitrous oxide, a potent greenhouse gas, from the sea.

Dr Galloway says the aim is to maximise the effectiveness of nitrogen in food production while minimising the effects on the environment and human health. There is room for improvement. Existing technology can remove nitrogen oxides when fossil fuels burn, at a cost. Breeding or genetic modification could increase the efficiency with which animals and plants take up nitrogen. Improving animal management (with better diets and use of manure), would also help. And if only half of the sewage of the 3.2 billion people living in cities were treated, the environment would be spared about 5m tonnes of reactive nitrogen a year. Altogether, such interventions would add up to about 54m tonnes of less reactive nitrogen, about 28% of what was created in 2005.

Already cap-and-trade schemes are springing up in some American watersheds because of concern about the spread of dead zones. They work in the same way as America's sulphur-dioxide trading scheme and Europe's emissions-trading scheme for carbon. Polluters trade the right to pollute with substances such as nitrogen. Although this can be cost-effective, it is likely to work only when pollutants come from identifiable sources.

Dr Galloway's next task is to create a nitrogen-footprint calculator on the internet, which would be similar to a carbon-footprint calculator.

Although there seems to be little prospect of any immediate and concerted action to try to restore the Gulf of Mexico's dead zone, the north-western coastal area of the Black Sea provides an accidental example of how some places might, if given the chance, improve very quickly. After the collapse of the centrally planned economies of eastern and central Europe, the use of manufactured fertilisers declined because they were no longer affordable. Within seven years the Black Sea's dead zone had largely vanished and fisheries had recovered. That, at least, is cause for a little spring cheer.

Naughty nesters

May 8th 2008
From The Economist print edition

How cuckoos trick their way into another bird's nest

CUCKOLDS are men whose wives gave birth to infants that were blatantly not their own. The well known trickery of the cuckoo, the bird from which “cuckold” is derived, is as a nest parasite—laying eggs for other birds to hatch and raise. New research suggests the cuckoo has another trick it uses to ruffle its victims' feathers.

Common cuckoos usually lay a single egg in the nest of a host bird. The eggs often look remarkably similar to the host's. Upon hatching, the cuckoo chick eliminates any of its potential rival chicks by pushing them or their eggs out of the nest. However, there is more to this elaborate deceit than is generally realised.

As far back as ancient times a similarity has been noted between many cuckoo species and hawks; in size, shape and plumage. More recently researchers have discovered that hawk-like markings are more prevalent in cuckoo species that engage in nest parasitism than in cuckoo species that do not. Nick Davies and Justin Welbergen at the University of Cambridge wondered whether this similarity was noticed by birds too.

They set up peanut feeding stations and over two years found that great and blue tits, both of which are not parasitised by cuckoos, were the main visitors. They then experimented by placing a mounted specimen of a sparrowhawk, cuckoo, dove, or duck, at the feeders for five minutes. The team report in the Proceedings of The Royal Society that the tits were as scared of cuckoos as they were of sparrowhawks, raising alarm calls and staying away from feeders at all costs. With the duck and dove they detected no such behaviour.

When Dr Davies covered the hawk-like markings on the cuckoo the tits treated it as if it were a duck or dove. Covering the same markings on the sparrowhawk had no such effect, but adding them to the dove caused the tits to treat the dove as they would a sparrowhawk or a cuckoo.

The authors argue that actual cuckoo hosts, such as meadow pipits, dunnocks and reed warblers, may have directed the evolution of the cuckoo's resemblance to hawks by attacking cuckoos that approached their nests. If a cuckoo with slightly hawk-like plumage caused hosts to delay or avoid an attack in the past, this would have favoured the evolution of hawk mimicry.

It is an arms race—and a matter of adapting and counter-adapting, explains Dr Welbergen. The better the cuckoo disguises its eggs and itself, the more host birds improve their ability to spot the impostor. Although such an evolutionary dynamic may seem like something that exists only in the wild, it is possible for it to happen in human society as well—between cuckolds and their cheating partners, constantly driving men to be better at detecting adultery and women to be better at getting away with it.