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Where blue eyes came from

Matt Ridley — Sun, 29 Jan 2012 09:07:35 +0000

Matt Ridley

How culture can change genes

My latest Mind and Matter column for the Wall Street Journal is on gene-culture co-evolution:

Human beings, we tend to think, are at the mercy of their genes. You either have blue eyes or you do not (barring contact lenses); no amount of therapy can change it. But genes are at the mercy of us, too. From minute to minute, they switch on and off (i.e., are actively used as recipes to make proteins) in the brain, the immune system or the skin in response to experience. Sunbathing, for example, triggers the expression of genes for the pigment melanin.

As a recent study confirms, on a much longer time scale, genes are even at the mercy of culture. The paradigmatic example is lactose tolerance. All mammals can digest lactose sugars in milk as babies, but the lactase gene switches off at weaning when no longer needed. In much of Europe and parts of Africa, by contrast, most people can digest lactose even as adults, because the lactase gene remains switched on. (About 90% of East Asians and 70% of South Indians are lactose-intolerant to some degree.)

This "lactase persistence" is caused by one of four genetic mutations that occurred in different regions and at different dates, one in Europe and three in Africa. Coincidentally, these regions also saw the domestication of cattle and the adoption of milk-drinking by adults around the same time. Of course, it's plausible that the culture came first—drinking milk gave some advantage to all, because milk has nutrition other than lactose in it, but it especially benefited adults with mutations that allowed lactose digestion. So such mutations spread.

The new study, of 5,000-year-old bones from the Basque region of Spain, catches this evolutionary event in the act, finding that just 27% of individuals were then lactose tolerant, much lower than today. Concepción de la Rúa of Spain's University of the Basque Country and her fellow authors conclude that the genetic change most probably happened after cattle domestication, at a time "when fresh milk consumption was already fully adopted as a consequence of a cultural influence." Here we have genes at the mercy of culture.

Could blue eyes be another example of the same phenomenon—"culture-gene co-evolution"? Thanks to the work of the appropriately named (and blue-eyed) Danish geneticist Hans Eiberg and his colleagues, we now know that the chief mutation that causes blue eyes is a single letter change, from A to G, at the 26,039,213rd position on chromosome 15, within a gene called HERC2.

HERC2 has no effect on eye color, but it contains an unexpressed segment of DNA that is needed for the switching on of a nearby gene called OCA2, as demonstrated by newly published work by Robert-Jan Palstra and others at Erasmus University in the Netherlands. The mutation that causes blue eyes reduces the expression of OCA2 and hence reduces pigment concentration. Paler eyes look bluer.

Why did this mutation become so common somewhere around the shores of the Baltic sea around 6,000 years ago? The answer may lie in the fact that the date coincides with the arrival of agriculture in the area. When people began relying heavily on a diet of bread at such a northern latitude, they probably became chronically deficient in vitamin D, for bread is generally low in vitamin D.

This wouldn't matter in a lower latitude, because the body can synthesize vitamin D if exposed to ultraviolet sun rays. But in northern Europe, diseases related to vitamin D deficiency, such as rickets, would have become common. Any individual who had a genetic mutation that lightened his or her skin (and eyes) would absorb more sunlight, boosting health and the ability to survive and breed. Paleness was selected.

When Nordic people started depending more on bread than on fish, they got less vitamin D from their diet. As a result, they got paler, improving the capacity of their skin to generate this crucial nutrient just from scarce sunlight. How they lived changed, in effect, how they looked.

On ice

Matt Ridley — Sat, 28 Jan 2012 08:02:57 +0000

Matt Ridley

Eschenbach's essays are worth reading

One of my favourite writers these days is Willis Eschenbach, whose essays at wattsupwiththat often combine ingenious scientific rationality with lyrical prose. Here he is on the subject of the sea ice off Alaska:

My point in this post? Awe, mostly, at the damaging power of cold. As a seaman, cold holds many more terrors than heat. When enough ice builds up on a boat’s superstructure, it rolls over and men die. The sun can’t do that. The Titanic wasn’t sunk by a heat wave.

The thing about ice? You can’t do a dang thing about it. You can’t blow up a glacier, or an ice sheet like you see in the Bering Sea above. You can’t melt it. The biggest, most powerful icebreaker can’t break through more than a few feet of it. When the ice moves in, the game is over.

Now me, I’m a tropical boy. My feeling is that well-behaved ice sits peacefully in my margarita glass, making those lovely cold drips run down the outside, and giving me a brain freeze when I hold the glass to my forehead.

But when ice jumps out of my glass and starts running all around painting the landscape white and solidifying the ocean and falling on my head and freezing my … begonias, well, at that point the fun’s over. I call that “water behaving badly”.

The distorting of the human sex ratio

Matt Ridley — Sun, 22 Jan 2012 13:55:22 +0000

Matt Ridley

Technology and prosperity make sex selective abortion easier

My latest Mind and Matter column in the Wall Street Journal:

Even a rational optimist is pessimistic about some things. Here's one: the gradual distortion of the human sex ratio by sex-selective abortion. A new essay by the demographer Nicholas Eberstadt concludes that "the practice has become so ruthlessly routine in many contemporary societies that it has impacted their very population structures." He finds "ample room for cautious pessimism" in the fact that this phenomenon is still very much on the increase.

For obscure reasons, the human sex ratio is always slightly male-biased, but in the natural state it rarely goes above 105 male births per 100 female ones, except in small samples. In China's last mini-census in 2005, the ratio was nearly 120 to 100 and in some districts over 150. That this is caused by sex-selective abortion (and not, for example, by a hepatitis-B epidemic, which can favor male births) is proved by a ratio of 107 to 100 among first-born children but nearer 150 among ones born later.

China is not the only country where this is happening. By the early 21st century, all four Asian "tigers"—South Korea, Singapore, Hong Kong and Taiwan—had a "naturally impossible" ratio of 108 or higher. India has an increasing ratio, as high as 120 in some states. Even some European and central Asian countries (including Albania, Georgia and even Italy) have unnaturally male-biased births. Nearly half the world falls in this category.

For 2005 to 2010, the United Nations puts the world sex ratio at birth at 107 boys to 100 girls. Assuming 105 is natural, Dr. Eberstadt calculates that this translates into a global "girl deficit" of at least 32 million. The consequences, in terms of unmarried and perhaps disruptive men, may be serious and long-lasting.

The phenomenon apparently gets worse with prosperity. Countries like Vietnam have shown male-biased birth ratios only since starting to grow rapidly richer. An analysis by Christophe Guilmoto and Sébastien Oliveau has shown that, in China and India, the problem is more acute in fairly rich regions.

Why? As people get richer, they plan smaller families, and those who have had a girl first are prepared to go to great lengths to ensure having a boy the next time. Economic growth also means more access to ultrasound scanning and abortion. Female infanticide after birth still happens, but it is both psychologically harder than abortion and less easy to disguise as a medical necessity.

Of course, near-perfect sex selection can be achieved with in-vitro fertilization (by implanting only male embryos), but this will remain a luxury of the very rich. What about sperm selection? A clinical trial getting under way in the U.S. will test a method for sorting human sperm into X (female determining) and Y (male) types; it's already used in animals such as dairy cattle with 93% accuracy. If this method becomes cheap, it's easy to imagine clinics offering it in China and India.

Policy seems largely powerless to fight this problem. Sex-selective abortion is illegal in virtually all countries. China's authoritarian "one-child policy" is in marked contrast with India's more laissez-faire attitude to family planning, yet both have produced widespread killing of female fetuses.

All of this presupposes a continuing general preference for boys in such societies, something that should eventually wane as their economies develop more equal employment opportunities. Given the way in which technology is evolving to make sex selection easier, perhaps the only short-term hope is to shame people. South Korea's sex ratio at birth reached 115 to 100 in the 1990s but has since fallen back to 107, thanks to what Mr. Eberstadt calls a "spontaneous and largely uncoordinated congealing of a mass movement for honoring, protecting and prizing daughters."

The best explanation in the world

Matt Ridley — Mon, 16 Jan 2012 08:43:09 +0000

Matt Ridley

Never has a mystery been so instantly explained as life

Each year, John Brockman's website, The Edge, asks a question and gets many answers to it. This year, the question is: What is your favourite deep, elegant, or beautiful explanation? Some of the answers are fascinating. Here's mine:

It's hard now to recall just how mysterious life was on the morning of 28 February 1953 and just how much that had changed by lunchtime. Look back at all the answers to the question "what is life?" from before that and you get a taste of just how we, as a species, floundered. Life consisted of three-dimensional objects of specificity and complexity (mainly proteins). And it copied itself with accuracy. How? How do you set about making a copy of a three-dimensional object? How to do you grow it and develop it in a predictable way? This is the one scientific question where absolutely nobody came close to guessing the answer. Erwin Schrodinger had a stab, but fell back on quantum mechanics, which was irrelevant. True, he used the phrase "aperiodic crystal" and if you are generous you can see that as a prediction of a linear code, but I think that's stretching generosity.

Indeed, the problem had just got even more baffling thanks to the realization that DNA played a crucial role—and DNA was monotonously simple. All the explanations of life before 28 Feb 1953 are hand-waving waffle and might as well speak of protoplasm and vital sparks for all the insights they gave.

Then came the double helix and the immediate understanding that, as Crick wrote to his son a few weeks later, "some sort of code"—digital, linear two-dimensional, combinatorially infinite and instantly self-replicating—was all the explanation you needed. Never has a mystery seemed more baffling in the morning and an explanation more obvious in the afternoon.

Here's part of Francis Crick's letter, 17 March 1953:

"My dear Michael,

Jim Watson and I have probably made a most important discovery...Now we believe that the DNA is a code. That is, the order of the bases (the letters) makes one gene different from another gene (just as one page pf print is different from another). You can see how Nature makes copies of the genes. Because if the two chains unwind into two separate chains, and if each chain makes another chain come together on it, then because A always goes with T, and G with C, we shall get two copies where we had one before. In other words, we think we have found the basic copying mechanism by which life comes from life...You can understand we are excited."

The slow cooling of our interglacial

Matt Ridley — Sat, 14 Jan 2012 19:34:45 +0000

Matt Ridley

Is an ice age imminent and will it be temporarily or permanently averted?

Here's my latest Mind and Matter column in the Wall Street Journal, with added links and charts. On interglacials.

The entire 10,000-year history of civilization has happened in an unusually warm interlude in the Earth's recent history. Over the past million years, it has been as warm as this or warmer for less than 10% of the time, during 11 brief episodes known as interglacial periods. One theory holds that agriculture and dense settlement were impossible in the volatile, generally dry and carbon-dioxide-starved climates of the ice age, when crop plants would have grown more slowly and unpredictably even in warmer regions.

This warm spell is already 11,600 years old, and it must surely, in the normal course of things, come to an end. In the early 1970s, after two decades of slight cooling, many scientists were convinced that the moment was at hand. They were "increasingly apprehensive, for the weather aberrations they are studying may be the harbinger of another ice age," said Time in 1974. The "almost unanimous" view of meteorologists was that the cooling trend would "reduce agricultural productivity for the rest of the century," and "the resulting famines could be catastrophic," said Newsweek in 1975.

Since then, of course, warmth has returned, probably driven at least partly by man-made carbon-dioxide emissions. A new paper, from universities in Cambridge, London and Florida, drew headlines last week for arguing that these emissions may avert the return of the ice age. Less noticed was the fact that the authors, by analogy with a previous warm spell 780,000 years ago that's a "dead ringer" for our own, expect the next ice age to start "within about 1,500 years." Hardly the day after tomorrow.

Still, it's striking that most interglacials begin with an abrupt warming, peak sharply, then begin a gradual descent into cooler conditions before plunging rather more rapidly toward the freezer. The last interglacial—which occurred 135,000 to 115,000 years ago (named the Eemian period after a Dutch river near which the fossils of warmth-loving shell creatures of that age were found)—saw temperatures slide erratically downward by about two degrees Celsius between 127,000 and 120,000 years ago, before a sharper fall began. See charts here and here.

Cyclical changes in the earth's orbit probably weakened sunlight in the northern hemisphere summer and thus caused this slow cooling. Since the northern hemisphere is mostly land, this change in the sun's strength meant gradually increased snow and ice cover, which in turn reflected light back into space. This would have further cooled the air and, gradually, the ocean too. Carbon-dioxide levels did not begin to fall much until about 112,000 years ago, as the cooling sea absorbed more of the gas.

Our current interglacial shows a similar pattern. Greenland ice cores and other proxy records show that temperatures peaked around 7,000 years ago, when the Arctic Ocean was several degrees warmer than today, trees grew farther north in Siberia and the Sahara was wet enough for hippos (Africa generally gets wetter in warm times). Data from the southern hemisphere reveal that this "Holocene Optimum" was global in extent. Here's an example:

source: Willis Eschenbach, wattsupwitthat

An erratic decline in temperature followed, with Minoan, Roman and Medieval warm periods peaking at successively lower temperatures, culminating in the exceptionally cool centuries of the "Little Ice Age" between 1550 and 1850, when glaciers advanced all over the world. In the Greenland ice cores, these centuries stand out as the longest and most consistent cold spell of the current interglacial.

source: murdoconline

In other words, our own interglacial period has followed previous ones in having an abrupt beginning and a sharp peak, followed by slow cooling. The question is whether recent warming is a temporary blip before the expected drift into glacial conditions, or whether humankind's impact on the atmosphere has now reversed the cooling trend.

Noise versus signal

Matt Ridley — Sat, 07 Jan 2012 21:36:20 +0000

Matt Ridley

Ocean alkalinity varies more than expected and dwarfs the trend caused by carbon dioxide emissions

My latest Mind and Matter column in the Wall Street Journal:

Coral reefs around the world are suffering badly from overfishing and various forms of pollution. Yet many experts argue that the greatest threat to them is the acidification of the oceans from the dissolving of man-made carbon dioxide emissions.

The effect of acidification, according to J.E.N. Veron, an Australian coral scientist, will be "nothing less than catastrophic.... What were once thriving coral gardens that supported the greatest biodiversity of the marine realm will become red-black bacterial slime, and they will stay that way."

This is a common view. The Natural Resources Defense Council has called ocean acidification "the scariest environmental problem you've never heard of." Sigourney Weaver, who narrated a film about the issue, said that "the scientists are freaked out." The head of the National Oceanic and Atmospheric Administration calls it global warming's "equally evil twin."

But do the scientific data support such alarm? Last month scientists at San Diego's Scripps Institution of Oceanography and other authors published a study showing how much the pH level (measuring alkalinity versus acidity) varies naturally between parts of the ocean and at different times of the day, month and year.

"On both a monthly and annual scale, even the most stable open ocean sites see pH changes many times larger than the annual rate of acidification," say the authors of the study, adding that because good instruments to measure ocean pH have only recently been deployed, "this variation has been under-appreciated." Over coral reefs, the pH decline between dusk and dawn is almost half as much as the decrease in average pH expected over the next 100 years. The noise is greater than the signal.

Another recent study, by scientists from the U.K., Hawaii and Massachusetts, concluded that "marine and freshwater assemblages have always experienced variable pH conditions," and that "in many freshwater lakes, pH changes that are orders of magnitude greater than those projected for the 22nd-century oceans can occur over periods of hours."

This adds to other hints that the ocean-acidification problem may have been exaggerated. For a start, the ocean is alkaline and in no danger of becoming acid (despite headlines like that from Reuters in 2009: "Climate Change Turning Seas Acid"). If the average pH of the ocean drops to 7.8 from 8.1 by 2100 as predicted, it will still be well above seven, the neutral point where alkalinity becomes acidity.

The central concern is that lower pH will make it harder for corals, clams and other "calcifier" creatures to make calcium carbonate skeletons and shells. Yet this concern also may be overstated. Off Papua New Guinea and the Italian island of Ischia, where natural carbon-dioxide bubbles from volcanic vents make the sea less alkaline, and off the Yucatan, where underwater springs make seawater actually acidic, studies have shown that at least some kinds of calcifiers still thrive—at least as far down as pH 7.8.

In a recent experiment in the Mediterranean, reported in Nature Climate Change, corals and mollusks were transplanted to lower pH sites, where they proved "able to calcify and grow at even faster than normal rates when exposed to the high [carbon-dioxide] levels projected for the next 300 years." In any case, freshwater mussels thrive in Scottish rivers, where the pH is as low as five.

Laboratory experiments find that more marine creatures thrive than suffer when carbon dioxide lowers the pH level to 7.8. This is because the carbon dioxide dissolves mainly as bicarbonate, which many calcifiers use as raw material for carbonate.

Human beings have indeed placed marine ecosystems under terrible pressure, but the chief culprits are overfishing and pollution. By comparison, a very slow reduction in the alkalinity of the oceans, well within the range of natural variation, is a modest threat, and it certainly does not merit apocalyptic headlines.

Catching species in the act of being born

Matt Ridley — Tue, 03 Jan 2012 16:18:51 +0000

Matt Ridley

Nine different South American finches may be incipient species

My Mind and Matter column for the Wall Street Journal on 1 January 2012 is here:

Here's a New Year's thought. With some nine million species on the planet, and with each species lasting a million years on average, about nine species will go extinct naturally this coming year (with more, almost certainly, going extinct unnaturally). But about nine new species also will be born in 2012.

Biologists have long dreamed of catching a new species in the act of forming. The problem, of course, is the time scale—and the fact that most species are little-known beetles and bugs. New species form constantly, but they take huge stretches of time to do so. The actual moment when a "daughter" species can (or will) no longer cross-breed with the population from which it sprang (the definition of speciation) is almost impossible to pinpoint, let alone to witness.

The best that evolutionary biologists can do is usually to point to groups of species that have plainly diversified recently, usually on a group of islands. The finches of the Galapagos, known as Darwin's finches, are the best known example, a single ancestral species from South America having given rise to 15 specialized forms in just the last two million years. More impressively, the cichlid fishes of Lake Victoria have generated 500 forms in about 14,000 years (lakes are islands of water).

Now scientists have described a group of continental, rather than island, bird species that seem to be in the process of forming new species. The southern capuchinos are nine species of small seed-eating birds in South America (a missing "p" and a substituted "h" separating their name from that of frothy Italian coffee). Though the brown females are similar to each other, the males wear strikingly different colors and sing quite distinct songs.

Yet, beneath the genetic surface, the nine species of southern capuchino do not look like different species at all. Their genetic "bar codes," based on DNA sequences unrelated to appearance or song, completely overlap—meaning that the species cannot be identified from genetic fingerprinting. It is as if they are one big species with lots of differently colored males.

Still, the species do lead fairly separate lives. Though capable of hybridizing, they plainly do not do so much. The explanation for this paradox, put forward by Leonardo Campagna of the Argentine Museum of Natural Sciences, is that they are incipient species, separated by the mating preferences of females but not yet by genetics.

Mr. Campagna and his colleagues argue that at some time in the past few hundred thousand years, during a part of the ice age when much of South America was covered with grasslands, an ancestral species of capuchino expanded rapidly across the continent. When warmer and wetter conditions returned, the birds became isolated in several islands of grass in a sea of forest. Each "island" developed its own idiosyncratic plumage and song. Now the species encounter each other again, but this time as distinct forms.

The starlings and sparrows that Europeans brought to North America may one day evolve sufficient differences from those left behind in Europe that they will constitute separate species. Given enough time, town pigeons in New York may one day be averse to cohabiting with town pigeons in San Francisco.

Initially, at least, this "man-made" biodiversity will be far too small and slow to compensate for man-made extinctions, but it's worth noting the possibility.

When less means more

Matt Ridley — Mon, 26 Dec 2011 07:35:34 +0000

Matt Ridley

Sometimes detailed analysis makes for worse decision making than simple rules of thumb

Here is the Mind and Matter column in the Wall Street Journal, published on 24th December.

Which American city has more inhabitants: San Antonio or San Diego? More Germans than Americans get the answer right (San Diego). What about Hanover or Bielefeld? More Americans than Germans get the answer right (Hanover). In each case, the foreigners pick the right answer by choosing the city they have heard more about, assuming that it's bigger. The natives know too much and let the excess information get in the way.

This is an example of a "heuristic," a highfalutin name for a "rule of thumb" or "gut feeling." Most business people and physicians privately admit that many of their decisions are based on intuition rather than on detailed cost-benefit analysis. In public, of course, it's different. To stand up in court and say you made a decision based on what your thumb or gut told you is to invite damages. So both business people and doctors go to some lengths to suppress or disguise the role that intuition plays in their work.

Prof. Gerd Gigerenzer, the director of the Max Planck Institute for Human Development in Berlin, thinks that instead they should boast about using heuristics. In articles and books over the past five years, Dr. Gigerenzer has developed the startling claim that intuition makes our decisions not just quicker but better. He rejects the notion that hunches are second best, trading off accuracy for effort to achieve decisions that are "good enough" but not perfect.

As Dr. Gigerenzer sees it, complex problems do not necessarily need complex solutions, and more detailed analysis does not necessarily improve a decision, but often makes it worse. He believes, in effect, that less is more: Extra information distracts you from focusing on the few simple aspects of a problem that matter most.

A baseball player running to catch a fly ball is not behaving, even unconsciously, as if he were solving differential equations to work out where the ball will land. He is following a simple rule: Keep the angle of the falling ball constant in your vision and adjust your running speed accordingly. It's the same trick used by dragonflies catching flies.

When Jeffrey Skiles, the co-pilot of the plane that made an emergency landing in the Hudson River in January 2009, explained how he and his captain decided that an airport landing was impossible, he described the same "gaze heuristic": The angle of the plane's descending glide made the airport appear to rise in their windscreen view—clearly signaling that a landing there was doomed.

The economist Harry Markowitz won the Nobel prize for designing a complex mathematical formula for picking fund managers. Yet when he retired, he himself, like most people, used a simpler heuristic that generally works better: He divided his retirement funds equally among a number of fund managers.

A few years ago, a Michigan hospital saw that doctors, concerned with liability, were sending too many patients with chest pains straight to the coronary-care unit, where they both cost the hospital more and ran higher risks of infection if they were not suffering a heart attack. The hospital introduced a complex logistical model to sift patients more efficiently, but the doctors hated it and went back to defensive decision-making.

As an alternative, Dr. Gigerenzer and his colleagues came up with a "fast-and-frugal" tree that asked the doctors just three sequential yes-no questions about each patient's electrocardiographs and other data. Compared with both the complex logistical model and the defensive status quo, this heuristic helped the doctors to send more patients to the coronary-care unit who belonged there and fewer who did not.

It is no surprise that in the wake of the great financial crisis, financial regulators are beating a path to Dr. Gigerenzer's door. The complex algorithms that gave AAA ratings to debts that should not have passed the smell test demonstrated all too well the futility of knowing too much.

For a video showing Gigerenzer presenting his ideas in a lecture, see here.

Don't be such a Higgs Boson

Matt Ridley — Sun, 18 Dec 2011 16:00:27 +0000

Matt Ridley

We need a metaphor for those who impede progress. The Higgs Boson might do.

My latest Mind and Matter column for the Wall Street Journal is on metaphors for the Higgs Boson.

In 1993 a British science minister, William Waldegrave, was sitting on a train reading the speech that his staff had prepared for him for a physics conference. Finding the draft "unspeakably dull," he decided instead to challenge the assembled scientists to answer, on a single sheet of paper, the question: "What is the Higgs boson, and why do we want to find it?" He pledged to the winner a bottle of vintage Champagne.

Even before its existence was at last tentatively suggested by an experiment this week, many people had heard of the Higgs boson, the mysterious manifestation of the field that causes matter to have mass, according to a theory minted in 1964. Yet almost nobody, myself included, knows what a Higgs boson is, or at least can give a sensible description of it. This is a serious handicap if Higgsism, as I hereby christen it, is to have an impact on human culture, let alone on technology.

Most scientific discoveries can be boiled down to a sound bite, however imperfectly. Black holes are so dense that they do not even let light out. Genes are pieces of heredity. Vaccination is a medical procedure that works by stimulating the body's immune system. And so on.

In particle physics, sound-bite explanations are much harder: wave-particle duality, quantum mechanics, general relativity and string theory make good mathematical sense, or so I am told, but they generally defy translation into English. So do philosophical conundrums like free will—a subject whose paradoxes seem all but impossible to capture in language. Can the Higgs boson be made intuitively comprehensible?

Out of hundreds of entries responding to Mr. Waldegrave's challenge, the judges chose five winners (costing the minister five bottles of fine Champage, from his own pocket). The striking thing about the essays is how much they resorted to analogy to explain Higgsism.

The most memorable metaphor was offered by David Miller of University College, London. Since Mr. Waldegrave had been a colleague of Margaret Thatcher, Mr. Miller chose to portray the Higgs field thus: "Imagine a cocktail party of political-party workers who are uniformly distributed across the floor, all talking to their nearest neighbors. The ex-prime minister enters and crosses the room. All of the workers in her neighborhood are strongly attracted to her and cluster round her. As she moves, she attracts the people she comes close to, while the ones she has left return to their even spacing."

The party-goers are the Higgs field, which gives mass to particles like electrons (Lady Thatcher) by viscously impeding their progress. "Once moving, she is harder to stop, and once stopped, she is harder to get moving again because the clustering process has to be restarted." The Higgs boson itself he compared to a rumor spreading through the party, causing a wave of local clustering in the Higgs field.

As for the second part of Mr. Waldegrave's question—"why do we want to find it?"—the essays gave few answers beyond the pursuit of knowledge as an end in itself. The Higgs boson feels untouchably esoteric, a fragment of pure knowledge that may never be applied in the practical world. But the same could have been said of the theory of general relativity, and yet satellite navigation, on which we all now depend, would be riddled with inaccuracies without corrections derived from it.

Even without eventual practical use, it would be good if the Higgs boson had a cultural impact, by moving into the language as a metaphor, just as "light year," "Darwinian," "subconscious" and "in the DNA" have done.

Perhaps the way that a bureaucracy impedes, delays and weighs down a simple course of action could henceforth be described as Higgsian. When a committee member proposes a time-wasting complication, one could cry out, "Don't be such a Higgs boson!" Just a suggestion.

Bioenergy versus the planet

Matt Ridley — Thu, 15 Dec 2011 18:54:10 +0000

Matt Ridley

Biomass and biofuels are not carbon neutral, can't displace much fossil fuel, require huge subsidies, increase hunger and directly or indirectly cause rain forest destruction. Apart from that...

Prospect has published my essay on bioenergy, in which my research left me astonished at the environmental and economic harm that is being perpetrated. Biomass and biofuels are not carbon neutral, can't displace much fossil fuel, require huge subsidies, increase hunger and directly or indirectly cause rain forest destruction. Apart from that, they're fine... Here's the text:

From a satellite, the border between Haiti and the Dominican Republic looks like the edge of a carpet. While the Dominican Republic is green with forest, Haiti is brown: 98 per cent deforested. One of the chief reasons is that Haiti depends on bioenergy. Wood—mostly in the form of charcoal—is used not just for cooking but for industry as well, providing 70 per cent of Haiti’s energy. In contrast, in the Dominican Republic, the government imports oil and subsidises propane gas for cooking, which takes the pressure off forests.

Haiti’s plight is a reminder there is nothing new about bioenergy. A few centuries ago, Britain got most of its energy from firewood and hay. Over the years the iron industry moved from Sussex to the Welsh borders to Cumberland and then Sweden in an increasingly desperate search for wood to fire its furnaces. Cheap coal and oil then effectively allowed the gradual reforestation of the country. Britain’s forest cover—12 per cent—is three times what it was in 1919 and will soon rival the levels recorded in the Doomsday Book of 1086.

Yet if the government has its way, we will instead emulate Haiti. In 2007, Tony Blair signed up to a European Union commitment that Britain would get 20 per cent of its energy from renewable sources by 2020. Apparently neither he nor his officials noticed this target was for “energy” not “electricity.” Since much energy is used for heating, which wind, solar, hydro and the like cannot supply, this effectively committed Britain to using lots of wood and crops for both heat and electricity to hit that target. David Cameron and Chris Huhne, anxious to seem the “greenest of them all,” dare not weaken the target, despite its unattainability. Biomass consumption in power stations was up 27 per cent in 2010 and “co-firing” (burning biomass alongside coal) was up 39 per cent. To replace coal, the government projects that by 2020 Britain will be generating electricity from burning up to 60m tonnes of biomass, mainly wood, about five times the timber harvest that Britain could conceivably produce. To replace oil, the European Union has set a target of making 10 per cent of our transport fuel renewable by 2020, which will mean mainly biodiesel made from rape, soybean and imported palm oil. To replace gas, a gold rush of developers is trying to build anaerobic digesters on farms, where they will turn whole crops into methane.

All this is driven by subsidies that are mouth-wateringly generous to energy producers and eye-wateringly costly to consumers and drivers. According to the pressure group Biofuelwatch, the biomass power stations proposed for Britain would attract over £3bn a year through “renewable obligation certificates.” Drax power station alone gets £43m a year to “co-fire” biomass alongside coal, much of it imported—for example in the form of olive pits, sunflower husks and peanut shells.

For all the furore that wind farms attract, bioenergy is a much bigger drain on the public purse than wind. Bioenergy currently supplies 83 per cent of all renewable energy used in Britain, while wind, solar, hydro, tide, wave, geothermal and heat pumps manage just 17 per cent, or 1 per cent of total energy. About half of that bioenergy is from waste incineration, sewage and landfill gas. The rest comes from timber or crops. The uncomfortable truth is that more than four-fifths of all “renewable” energy involves burning something.

If you mention biomass crops to an environmentalist, he or she will usually agree they are a bad thing—for reasons I will come to—but claim that they have little to do with the green movement, being driven instead by American electoral politics. (Iowa, a key state for presidential candidates to win early support, benefits from subsidies when the maize grown there is turned into ethanol.) Inconveniently for this thesis, the amount of Britain’s primary energy supply from biomass (3 per cent) is about the same as America’s (4 per cent).

It was not US politics that caused a subsidised wheat ethanol plant to open on Teesside in 2009 (and then close in May because the smell was a nuisance and the wheat price had become too high). As Robert Palgrave of Biofuelwatch says: “In America, bioenergy’s supporters stress energy security; here the big driver has been climate change and in particular the European Union’s Renewable Energy Directive.”

Whether they admit it or not, the green movement caused this policy, the sole justification being to address climate change. Yet bioenergy is not just doing nothing to help cut carbon emissions— like wind; it is actually making the problem worse.

Here is why. A carbon atom is a carbon atom, wherever it comes from. Oxidise (burn) it and you get carbon dioxide. That is true whether it is in a hydrocarbon (like coal, oil or gas), a carbohydrate (like sugar in sugar cane or starch in maize), or a lipid (like oil from palm oil). Roughly one-third of the atoms we oxidise to liberate energy are carbon and two-thirds hydrogen. (Oxidised hydrogen is better known as water.)

As Jesse Ausubel of Rockefeller University has calculated, wood has a higher ratio of carbon to hydrogen (10) than coal (1), oil (0.5) and gas (0.25). Burn wood and you make 40 times more carbon dioxide for each unit of energy than if you burn gas. It’s the worst thing you can do in carbon terms.

However, a carbon atom in wood was absorbed from the air a few years before when the tree grew, whereas a carbon atom in coal or gas was absorbed from the air hundreds of millions of years before. Since a felled tree can be fairly quickly replaced by a new one, wood is said by its supporters to be “carbon neutral” whereas gas is not.

The trouble with this argument is that it fails to take into account the fact that burning the timber oxidises carbon atoms decades before they would be released naturally. According to a report from Joanneum Research, this up-front carbon debt could take two or three centuries to be paid back in the case of timber. Harvesting also denies the carbon atoms to other species, such as beetles and woodpeckers (whereas almost nothing eats coal or gas).

In the case of crops grown for liquid fuel, a bigger problem emerges: the carbon oxidised in planting, harvesting, transporting and drying the grain turns out to be about as much as the carbon content of the plant itself. That is to say, almost as many carbon atoms (and almost as much energy) are burned in making the fuel as are in it. This is the case for maize grown for ethanol in the US, for example. By contrast drilling for, transporting and refining petrol has a 600 per cent energy gain.

Some biofuels are better. Brazilian sugar cane, which supplies a third of all fuel used by cars in that country, contains more carbon atoms than were burned in growing it. But don’t celebrate too soon. The reason is that Brazilian sugar cane is mostly cut by poor labourers on piece rates, some of them children, rather than by machinery.

It gets worse. When a forest is felled to make way for a biofuel crop, the carbon stored in the trees and soil leaks into the atmosphere through decay. The crop is then grown with nitrogen fertiliser, some of which turns to nitrous oxide, a greenhouse gas 300 times more potent than carbon dioxide.

In Borneo vast areas of forest have been cleared to grow palm oil to make into biodiesel to sell to Europeans striving to meet their renewable targets. Much of this forest grew on waterlogged peat with high carbon content. When this is drained, the peat oxidises. Researchers at the University of Leicester have calculated that the carbon emissions from the drained peat are double the previous estimates of carbon emitted in the clearing of forests, so the policy of clearing forest for palm oil can “actually increase emissions relative to petroleum fuels.” It would take 423 years to pay back the up-front carbon debt.

This is to say nothing of the orangutans whose habitat is eroded and fragmented. The European Environment Agency (EEA) says that “accelerated destruction of rainforest due to increasing biofuel production can already be witnessed.”

Even if you do not clear rainforest to grow biofuels, you usually displace a food crop. This pushes up food prices, as a total of 17 independent reports have concluded. In August the UN Committee on World Food Security said biofuels had been a bigger cause of recent food price increases than the growth of the Asian middle class. The independent scholar Indur Goklany has estimated that biofuels killed 192,000 people in 2010 by increasing hunger.

Higher prices encourage farmers to cultivate more virgin land, so biofuels encourage the destruction of rainforest to grow food, even if they did not directly replace forest. Such “indirect land use change” is impossible to measure. The European Commission promised to come up with an estimate, but in September Reuters obtained a leaked report in which the commission admitted it could not put a number on the problem. A few days later the EEA issued a statement that because biofuels displace food crops, the assumption that they are carbon neutral is “not correct.”

An American study published in Science in 2008 concluded that because maize made into ethanol could not be exported as food, some virgin land would be cleared and ploughed elsewhere in the world for every acre of ethanol maize grown, which meant that ethanol had effectively double the carbon footprint of petroleum.

Britain gets most of its biofuel from Argentinian soybeans. A recent report commissioned by the Department of Energy and Climate Change concluded that if bioenergy grows to 20 per cent of primary energy by 2020 as envisaged, we will be importing 67 per cent of it. So not only is the impact on hunger and rainforest destruction directly on our conscience; there is also no prospect of energy security from bioenergy. This import dependence is causing second thoughts about how “sustainable” Britain’s rush to biomass really is, and that is frightening off the banks that would need to lend to such projects.

At this point, biofuel’s supporters argue that the second generation of biofuels, consisting of “cellulosic” miscanthus grass and jatropha plants, will be grown on marginal land not used for farming and not covered in rainforest. When asked where this land is, and how it can be made fertile enough to grow biofuels, they point to degraded and abandoned farmland. The trouble is, they forgot to tell the people who live there. Göran Berndes of Chalmers University of Technology in Sweden co-authored a report that studied 17 bioenergy feasibility studies. Its conclusion was that “land reported to be degraded is often the base of subsistence for the rural population.”

In Andhra Pradesh, Berndes did find that jatropha planting helped retain water and didn’t prevent land being grazed, so its impact was “generally positive, creating a complementary source of income to the farmers.” But elsewhere things are not so rosy. Fatou Mbaye, food rights co-ordinator for Action Aid Senegal, told the New Internationalist recently: “At first, we were told that [jatropha] would be grown on marginal land. But it’s being grown on the best arable land with the highest rainfall, or where good irrigation is possible, to make it economically profitable.”

While the impact of bioenergy on food prices has been severe, the reduction in oil use has been minuscule. In 2010, America turned 40 per cent of its maize crop into fuel, displacing just 3 per cent of its oil consumption. Worldwide, 5 per cent of grain was turned into fuel, displacing just 0.6 per cent of oil. To cut say 20 per cent of world oil use would require such a gigantic land grab that starvation would be widespread and rainforest a distant memory.

The land grab is huge because of bioenergy’s low power density. According to Jesse Ausubel, an American ethanol farm generates about 0.047 watts per square metre, once the energy inputs are deducted; a New England forest can provide wood at the rate of about 0.1 watts per square metre; and a Brazilian sugar cane field, ignoring human toil, manages about 3.7.

The energy expert Vaclav Smil of the University of Manitoba says a realistic estimate of the energy density of bioenergy worldwide is less than 0.5 watts per square metre. The world economy uses energy at the rate of 15,000 gigawatts (474 exajoules per year). To supply that from bioenergy would require 30 million square km, a territory the size of China, Brazil, India and Australia put together. Or “Renewistan” as engineer Saul Griffith calls this fabled land.

The champions of biofuels are left with one card to play: algae. In theory, by growing algae in closed bioreactors in salty water in sunny places, you can achieve much higher power densities. In practice, many engineering hurdles remain before first-generation algal farms go commercial.

The conclusion is stark. There is no way to run even a fraction of the world economy on bioenergy without severely damaging the planet. For the environment’s sake we must use a much denser form of energy, such as fossil fuel or nuclear, whose footprints I estimate to be about 100 and 10,000 times smaller than biofuel’s respectively. The same applies to other forms of renewable energy, with the possible exception of solar power, whose density could one day be better than the rest (except in cloudy Britain). So by all means install a wood-burning stove or use biodiesel in your car. But don’t pretend you are doing the planet a favour.

A declaration of interest. As a landowner I benefit from the recent increases in prices of wheat and wood caused by bioenergy. Recently I turned down a proposal to establish an anaerobic digester on my farm, even though it would have guaranteed a good income. So the views expressed here are against my financial interest.