Riderless-Bike Research

Monday, April 18th, 2011

Everyone knows that a moving bike tends to stay upright, but a stopped bike falls right over, and most people who’ve thought about it have assumed that two effects were responsible — gyroscopic effects and caster effects — but a new riderless bike takes those effects out of play without falling over:

The theory of gyroscopic precession holds that when a bike leans to the right or to the left, the spinning front wheel forces the bike to turn into the lean, effectively keeping it upright. Further, the caster effect likens the wheels of bicycles to those on shopping carts.

Next time you go to the grocery store, notice how the point of contact for the cart’s wheels are just behind the steering axis, which is the same imaginary line that extends downward from the forks of the bike. That makes wheels on casters self-righting: As soon as they start to tip, they turn into the direction of the fall, straightening themselves out again.

To debunk the theory, Papadopoulous and colleagues built a bike that eliminates both effects. The steering axis of their model lies behind the front wheel, canceling out the caster effect. And the addition of wheels situated above the front and back wheels, spinning in the opposite direction of each, counters the effect of gyroscopic precession.

They gave it a push and, you guessed it, the bike stayed balanced on its own.

The researchers found it has to do with the bike’s higher distribution of mass in the rear versus lower in the front. As the front of the bike will try to fall faster than the rear, the front is forced to steer into the fall and pull the bike out of tipping over.

Go East, young bureaucrat

Sunday, April 17th, 2011

Go East, young bureaucrat, urges The Economist, and learn from Singapore:

The Singaporeans argue that they have the perfect compromise between accountability and efficiency. Their politicians are regularly tested in elections and have to make themselves available to their constituents; but since the government knows it is likely to win, it can take a long view. Fixing things like ITE takes time. “Our strength is that we are able to think strategically and look ahead,” says the prime minister. “If the government changed every five years it would be harder.”

There is more truth in this than Western liberals would like to admit. Not many people in Washington are thinking beyond the 2012 presidential election. It is sometimes argued that an American administration operates strategically for only around six months, at the beginning of its second year — after it has got its staff confirmed by the Senate and before the mid-terms campaign begins.

Yet even assuming that voters are happy to swap a little more efficiency for less democracy, Singapore still seems a difficult model to follow. Not only is it manageably small, but balancing authoritarianism and accountability comes down largely to personal skills (and even the opposition admits that the two Lees have been extremely good at it). More generally, Singapore’s success as a planning state has a lot to do with the sort of people who run it.

One thing that stands out in Singapore is the quality of its civil service. Unlike the egalitarian Western public sector, Singapore follows an elitist model, paying those at the top $2m a year or more. It spots talented youngsters early, lures them with scholarships and keeps investing in them. People who don’t make the grade are pushed out quickly.

Sitting around a table with its 30-something mandarins is more like meeting junior partners at Goldman Sachs or McKinsey than the cast of “Yes, Minister”. The person on your left is on secondment at a big oil company; on your right sits a woman who between spells at the finance and defence ministries has picked up degrees from the London School of Economics, Cambridge and Stanford. High-fliers pop in and out of the Civil Service College for more training; the prime minister has written case studies for them. But it is not a closed shop. Talent from the private sector is recruited into both the civil service and politics. The current education minister used to be a surgeon.

Western civil services often have pretty good people at the top, but in Singapore meritocracy reigns all the way down the system. Teachers, for instance, need to have finished in the top third of their class (as they do in Finland and South Korea, which also shine in the education rankings). Headmasters are often appointed in their 30s and rewarded with merit pay if they do well but moved on quickly if their schools underperform. Tests are endemic.

How much strategic intervention takes place in the economy? The Lees have dabbled in industrial policy, betting first on manufacturing and then on services. Temasek manages a portfolio of S$190 billion ($150 billion). The country is now trying to push into creative industries, with limited success thus far, as ministers admit.

These attempts at dirigisme have made Singapore a more reserved, less entrepreneurial place than Hong Kong with its feverish laissez-faire. It certainly has far fewer larger-than-life billionaires. But it is hard to hail Singapore as a success of top-down economic management in the way some Chinese seem to think. Indeed, the core of Singapore’s success — its ability to attract foreign multinationals — owes far more to laissez-faire than to industrial policy.

Giving Doctors Orders

Saturday, April 16th, 2011

Maureen Dowd recommends giving doctors orders:

When my brother went into the hospital with pneumonia, he quickly contracted four other infections in the intensive care unit.

Anguished, I asked a young doctor why this was happening. Wearing a white lab coat and blue tie, he did a show-and-tell. He leaned over Michael and let his tie brush my sedated brother’s hospital gown.

“It could be anything,” he said. “It could be my tie spreading germs.”

I was dumbfounded. “Then why do you wear a tie?” I asked. He shrugged and left for rounds.

Michael died in that I.C.U. A couple years later, I read reports about how neckties and lab coats worn by doctors and clinical workers were suspected as carriers of deadly germs. Infections kill 100,000 patients in hospitals and other clinics in the U.S. every year.

A 2004 study of New York City doctors and clinicians discovered that their ties were contagious with at least one type of infectious microbe. Four years ago, the British National health system initiated a “bare below the elbow” dress code barring ties, lab coats, jewelry on the hands and wrists, and long fingernails.

The Centers for Disease Control and Prevention says that health care workers, even doctors and nurses, have a “poor” record of obeying hand-washing rules.

A report in the April issue of Health Affairs indicated that one out of every three people suffer a mistake during a hospital stay.

I saw infractions of the rules in the I.C.U. where Michael died, but I never called out anyone. I was too busy trying to ingratiate myself with the doctors, nurses and orderlies, irrationally hoping that they’d treat my brother better if they liked us.

The Real Villain

Saturday, April 16th, 2011

Ayn Rand’s works aren’t hard to caricature — which is why it’s so infuriating that the caricaturists routinely miss the point:

When Rand created the character of Wesley Mouch, it’s as though she was anticipating Barney Frank (D., Mass). Mouch is the economic czar in “Atlas Shrugged” whose every move weakens the economy, which in turn gives him the excuse to demand broader powers. Mr. Frank steered Fannie Mae and Freddie Mac to disaster with mandates for more lending to low-income borrowers. After Fannie and Freddie collapsed under the weight of their subprime mortgage books, Mr. Frank proclaimed last year: “The way to cure that is to give us more authority.” Mouch couldn’t have said it better himself.

But it’s a misreading of “Atlas” to claim that it is simply an antigovernment tract or an uncritical celebration of big business. In fact, the real villain of “Atlas” is a big businessman, railroad CEO James Taggart, whose crony capitalism does more to bring down the economy than all of Mouch’s regulations. With Taggart, Rand was anticipating figures like Angelo Mozilo, the CEO of Countrywide Financial, the subprime lender that proved to be a toxic mortgage factory. Like Taggart, Mr. Mozilo engineered government subsidies for his company in the name of noble-sounding virtues like home ownership for all.

Still, most of the heroes of “Atlas” are big businessmen who are unfairly persecuted by government. The struggle of Rand’s fictional steel magnate Henry Rearden against confiscatory regulation is a perfect anticipation of the antitrust travails of Microsoft CEO Bill Gates. In both cases, the government’s depredations were inspired by behind-the-scenes maneuverings of business rivals. And now Microsoft is maneuvering against Google with an antitrust complaint in the European Union.

The reality is that in Rand’s novel, as in life, self-described capitalists can be the worst enemies of capitalism. But that doesn’t fit in easily with the simple pro-business narrative about Rand now being retailed.

75, Including the Quigley

Saturday, April 16th, 2011

Within 40 days, a two-man British sniper team achieved 75 confirmed kills:

On one occasion they killed eight Taliban in two hours, ‘I wasn’t comfortable with it at first,’ said Osmond, ‘you start wondering is it really necessary?’ But the reaction of the locals soon persuaded him. ‘We had people coming up to us afterwards, not scared to talk to us. They felt they were being protected’.

This is gruesome but fascinating:

Most of the kills were at a range of 1,200 metres using the 7.62 mm L96 sniper rifle.

The snipers used suppressors, reducing the sound of the muzzle blast. Although a ballistic crack could be heard, it was almost impossible to work out where the shot was coming from. With the bullet travelling at three times the speed of sound, a victim was unlikely to hear anything before he died.

Walkie-talkie messages revealed that the Taliban thought they were being hit from helicopters. The longest-range shot taken was when Potter killed an insurgent at 1,430 metres away. But the most celebrated shot of their tour was by Osmond at a range of just 196 metres.

On September 12th, a known Taliban commander appeared on the back of a motorcycle with a passenger riding pillion. There was a British patrol in the village of Gorup-e Shesh Kalay and under the rules of engagement, the walkie-talkie the Taliban pair were carrying was designated a hostile act. As they drove off, Osmond fired warning shots with his pistol and then picked up his L96, the same weapon — serial number 0166 — he had used in Iraq and on the butt of which he had written, ‘I love u 0166’.

Taking deliberate aim, he fired a single shot. The bike tumbled and both men fell onto the road and lay there motionless. When the British patrol returned, they checked the men and confirmed they were both dead, with large holes through their heads.

The 7.62 mm bullet Osmond had fired had passed through the heads of both men. He had achieved the rare feat of ‘one shot, two kills’ known in the sniping business as ‘a Quigley’. The term comes from the 1990 film Quigley Down Under in which the hero, played by Tom Selleck, uses an old Sharps rifle to devastating effect.

Meat Contaminated with Staph

Friday, April 15th, 2011

Apparently half the meat in the US is contaminated with staph, and half of that is drug-resistant:

Researchers from the Translational Genomics Research Institute, a nonprofit biomedical research center in Phoenix, analyzed 136 samples of beef, chicken, pork and turkey from 80 brands. The samples came from 26 grocery stores in five cities: Los Angeles, Chicago, Fort Lauderdale, Fla., Flagstaff, Ariz., and Washington, D.C.

About half — 47% of the samples — contained S. aureus, the researchers reported Friday in Clinical Infectious Diseases. Of those bacteria, 52% were resistant to at least three classes of antibiotics. DNA testing suggested the animals were the source of contamination.

Knowledge Corrupts

Friday, April 15th, 2011

In 1968, when Kissinger was just entering the government, Daniel Ellsberg was analyzing the Vietnam War for the Pentagon and Rand, and he gave Kissinger this advice:

“Henry, there’s something I would like to tell you, for what it’s worth, something I wish I had been told years ago. You’ve been a consultant for a long time, and you’ve dealt a great deal with top secret information. But you’re about to receive a whole slew of special clearances, maybe fifteen or twenty of them, that are higher than top secret.

“I’ve had a number of these myself, and I’ve known other people who have just acquired them, and I have a pretty good sense of what the effects of receiving these clearances are on a person who didn’t previously know they even existed. And the effects of reading the information that they will make available to you.

“First, you’ll be exhilarated by some of this new information, and by having it all — so much! incredible! — suddenly available to you. But second, almost as fast, you will feel like a fool for having studied, written, talked about these subjects, criticized and analyzed decisions made by presidents for years without having known of the existence of all this information, which presidents and others had and you didn’t, and which must have influenced their decisions in ways you couldn’t even guess. In particular, you’ll feel foolish for having literally rubbed shoulders for over a decade with some officials and consultants who did have access to all this information you didn’t know about and didn’t know they had, and you’ll be stunned that they kept that secret from you so well.

“You will feel like a fool, and that will last for about two weeks. Then, after you’ve started reading all this daily intelligence input and become used to using what amounts to whole libraries of hidden information, which is much more closely held than mere top secret data, you will forget there ever was a time when you didn’t have it, and you’ll be aware only of the fact that you have it now and most others don’t…. and that all those other people are fools.

“Over a longer period of time — not too long, but a matter of two or three years — you’ll eventually become aware of the limitations of this information. There is a great deal that it doesn’t tell you, it’s often inaccurate, and it can lead you astray just as much as the New York Times can. But that takes a while to learn.

“In the meantime it will have become very hard for you to learn from anybody who doesn’t have these clearances. Because you’ll be thinking as you listen to them: ‘What would this man be telling me if he knew what I know? Would he be giving me the same advice, or would it totally change his predictions and recommendations?’ And that mental exercise is so torturous that after a while you give it up and just stop listening. I’ve seen this with my superiors, my colleagues….and with myself.

“You will deal with a person who doesn’t have those clearances only from the point of view of what you want him to believe and what impression you want him to go away with, since you’ll have to lie carefully to him about what you know. In effect, you will have to manipulate him. You’ll give up trying to assess what he has to say. The danger is, you’ll become something like a moron. You’ll become incapable of learning from most people in the world, no matter how much experience they may have in their particular areas that may be much greater than yours.”

….Kissinger hadn’t interrupted this long warning. As I’ve said, he could be a good listener, and he listened soberly. He seemed to understand that it was heartfelt, and he didn’t take it as patronizing, as I’d feared. But I knew it was too soon for him to appreciate fully what I was saying. He didn’t have the clearances yet.

(Hat tip to David Brooks.)

Beast’s Castle

Thursday, April 14th, 2011

Disney has a long history of using forced perspective at its parks, and Beast’s Castle, which they’re building as part of the new Fantasy Land in the Magic Kingdom, takes it to another level:

Learn the Fundamentals

Thursday, April 14th, 2011

It’s easier to learn the fundamentals before you’ve built up bad habits:

For example, when young children start working with music teachers, they start to work on simple music pieces. Easy music pieces of low to medium difficulty levels can be played with a wide range of playing styles, so there is no inherent need to acquire sound fundamental technique. However, when the students progress and attempt to master more advanced and difficult pieces that require higher speed and more expressive control, the quality of fundamental technique becomes the limiting factor for performance.

The music students with flawed fundamentals may at this point have reached a firm limit, unless they take off a year or two to focus on relearning the fundamentals correctly and then re-acquire the complex skills on that base.

Interestingly, recent investigations have observed neurological differences between students with flawed fundamentals and those possessing proper techniques (for a review, see Pascual-Leon, 2001). The importance of acquiring fundamental posture and movement patterns has also been demonstrated in some sports. For example, Law et al. (2007) found that world-class rhythmic gymnasts started their careers by studying classical ballet, a technically demanding form of dance, as children. In contrast, rhythmic gymnasts at the national level started with less structured dance activities, such as playful gymnastics.

Induction motors

Thursday, April 14th, 2011

Rare-earth elements have been in the news because the US hardly produces any these days, and one rare-earth, neodymium, makes super-strong permanent magnets, which go into permanent-magnet motors and generators.  But the induction motor designed by Nikola Tesla doesn’t use permanent magnets — and it has other advantages, too:

Tesla’s invention is, in essence, a rotating transformer. Its primary windings reside in a stationary steel casing (the stator) and and secondary conductors are attached to an inner shaft (the rotor). The stator surrounds — but does not touch — the rotor, which is free to rotate about its axis. An alternating current applied to the stator’s windings creates a rotating magnetic field, while simultaneously inducing a current in the separate conductors attached to the rotor. With an alternating current now circulating within it, the rotor creates a rotating magnetic field of its own, which then proceeds to chase the stator’s rotating field — causing the rotor to spin in the process and thereby generate torque.

Modern induction motors usually have three (or more) sets of stator windings, each using a different phase of the alternating current being applied. Having three “waves” of magnetism induced in the rotor with every revolution, instead of just one, smooths out the induction process and allows more torque to be generated.

Such machines are known as asynchronous motors, because the rotor’s magnetic field never catches up with the stator’s field. That distinguishes them from synchronous motors that use a permanent magnet in their rotors instead of a set of aluminium or copper conductors. In a synchronous motor, the stator’s rotating magnetic field imposes an electromagnetic torque directly on the fixed magnetic field generated by the rotor’s permanent magnet, causing the rotor-magnet assembly to spin on its axis in sync with the stator field. Hence the name.

In the past, the main disadvantage of asynchronous induction motors was the difficulty of varying their speed. That is no longer an issue, thanks to modern semiconductor controls. Meanwhile, the induction motor’s big advantage — apart from its simplicity and ruggedness — has always been its ability to tolerate a wide range of temperatures. Providing adequate cooling for the Toyota Prius’s permanent-magnet motor adds significantly to the vehicle’s weight. An induction motor, by contrast, can be cooled passively — and thereby dispense with the hefty radiator, cooling fan, water pump and associated plumbing.

Better still, by being able to tolerate temperatures that cause permanent magnets to break down, an induction motor can be pushed (albeit briefly) to far higher levels of performance — for, say, accelerating hard while overtaking, or when climbing a steep hill. Hybrid vehicles like the Toyota Prius or the Chevrolet Volt have to use their petrol engines to get extra zip. Pure electric vehicles such as the Nissan Leaf depend on gearboxes to generate the extra torque for arduous tasks. By contrast, the Tesla Roadster uses just one gear — such is the flexibility of its three-phase induction motor.
[...]
Weighing in at 52kg (115lb), the Tesla Roadster’s tiny three-phase induction motor is no bigger than a watermelon. Yet it packs a hefty 288 horsepower punch. More impressively, the motor’s 400 Newton-metres (295 lb-ft) of torque is available from rest to nearly 6,000 revolutions per minute. Having access to such a wide torque band eliminates the need for a second or third gear in the transmission. The result is a power unit that is light, compact and remarkably efficient.

Overall, the Tesla Roadster is said to achieve a battery-to-wheels efficiency of 88%—three times better than a conventional car.

Isocaloric but not Isometabolic

Wednesday, April 13th, 2011

Equal amounts of glucose and fructose may be isocaloric but not isometabolic:

This means we can eat 100 calories of glucose (from a potato or bread or other starch) or 100 calories of sugar (half glucose and half fructose), and they will be metabolized differently and have a different effect on the body. The calories are the same, but the metabolic consequences are quite different.

The fructose component of sugar and H.F.C.S. is metabolized primarily by the liver, while the glucose from sugar and starches is metabolized by every cell in the body. Consuming sugar (fructose and glucose) means more work for the liver than if you consumed the same number of calories of starch (glucose). And if you take that sugar in liquid form — soda or fruit juices — the fructose and glucose will hit the liver more quickly than if you consume them, say, in an apple (or several apples, to get what researchers would call the equivalent dose of sugar). The speed with which the liver has to do its work will also affect how it metabolizes the fructose and glucose.

In animals, or at least in laboratory rats and mice, it’s clear that if the fructose hits the liver in sufficient quantity and with sufficient speed, the liver will convert much of it to fat. This apparently induces a condition known as insulin resistance, which is now considered the fundamental problem in obesity, and the underlying defect in heart disease and in the type of diabetes, type 2, that is common to obese and overweight individuals. It might also be the underlying defect in many cancers.

If what happens in laboratory rodents also happens in humans, and if we are eating enough sugar to make it happen, then we are in trouble.

The Dan Plan

Wednesday, April 13th, 2011

I’ve been discussing the notion of deliberate practice and expertise, but Dan McLaughlin has decided to personally test the notion that 10,000 hours of practice can turn you into a pro:

Could he, an average man, 5 feet 9 and 155 pounds, become a pro golfer, just by trying? Dan’s not doing an experiment. He is the experiment.

The Dan Plan will take six hours a day, six days a week, for six years. He is keeping diligent records of his practice and progress. People who study expertise say no one has done quite what Dan is doing right now.

The rest of Dan’s high-achieving family has followed the normal road to success — college, grad school, respected profession — but Dan’s a bit unusual:

He went to Fiji with no guidebook during a military coup in which he saw men with machine guns at the airport and men with machetes outside. He biked through Thailand and Cambodia. He lived for five months in Australia, where he worked as a waiter because he arrived in the country with no money.

In Portland, throughout his late 20s, he took pictures of dental equipment, which let him buy his own home but also left him with a dissatisfied feeling. There had to be something more.

He started saving money for graduate school. He didn’t eat out or go to first-run movies and he rented out rooms in his house. He managed to save $100,000. When it came time to apply to grad school, though, that didn’t feel right, either.

He seems to be practicing deliberately:

He has three clubs in his bag, a putter, a chipper and a wedge. That’s it. That’s because of his coach.

Back when he first pitched his idea to Christopher Smith, a Nike-affiliated coach who has written a book about golf, Smith was not just uninterested. He was insulted. Golf is famously frustrating. Smith told Dan it was much harder than he thought. He told him to Google K. Anders Ericsson at Florida State University, a psychology professor and a leading expert on expertise.

Dan Googled him. Then called him. Then read his scholarly work. Smith started to think Dan was more committed than he had originally thought. Perhaps Dan was an opportunity. How would he teach golf to a person who was relatively fit, clearly willing and totally untouched, with no bad habits to undo because there were no habits at all?

Dan persuaded Smith to coach him. He got Nike to give him some free shoes, clothes and clubs. He set up a Twitter account, a Facebook page and a blog at thedanplan.com. By now, on Dan’s loose team of interested consultants are Smith, Ericsson, a personal trainer in Portland and a professor of kinesiology at the University of Nevada at Las Vegas.

Here’s how they have Dan trying to learn golf: He couldn’t putt from 3 feet until he was good enough at putting from 1 foot. He couldn’t putt from 5 feet until he was good enough putting from 3 feet. He’s working away from the hole. He didn’t get off the green for five months. A putter was the only club in his bag.

Everybody asks him what he shoots for a round. He has no idea. His next drive will be his first.

In his month in Florida, he worked as far as 50 yards away from the hole. He might — might — have a full set of clubs a year from now.

Most golfers don’t go pro, of course:

There are more than 27 million people in this country who play golf. There are 125 permanent spots on the PGA Tour.

Revolution U

Wednesday, April 13th, 2011

Egyptian revolutionaries arranged — via Facebook — protests and strikes for April 6, 2008, but these efforts failed.  Then the revolutionaries attended Revolution U, the Center for Applied Non-Violent Action, with its “professors” who had learned their craft running Otpor, the Serbian resistance movement:

But Otpor’s founders realized that young people would participate in politics — if it made them feel heroic and cool, part of something big. It was postmodern revolution. “Our product is a lifestyle,” Marovic explained to me. “The movement isn’t about the issues. It’s about my identity. We’re trying to make politics sexy.” Traditional politicians saw their job as making speeches and their followers’ job as listening to them; Otpor chose to have collective leadership, and no speeches at all. And if the organization took inspiration from Gandhi and Martin Luther King Jr., it also took cues from Coca-Cola, with its simple, powerful message and strong brand. Otpor’s own logo was a stylized clenched fist — an ironic, mocking expropriation of the symbol of the Serb Partisans in World War II, and of communist movements everywhere.

Otpor steered clear of the traditional opposition tactics of marches and rallies — partly out of necessity, because the group didn’t have enough people to pull them off. Instead of political parties’ gravity and bombast, Otpor adopted the sensibility of a TV show its leaders had grown up watching: Monty Python’s Flying Circus. Its daily work consisted of street theater and pranks that made the government look silly and won coverage from opposition media. Wit was perhaps not always achieved, but it was always the aim.

The most famous stunt involved an oil barrel painted with Milosevic’s picture. Otpor rolled it down a busy street, asking people to insert a coin in a slot for the privilege of whacking Milosevic with a bat. This was Otpor’s favorite kind of prank, a dilemma action: It left the regime damned either way. If the government had let the barrel roll, it would have looked weak. But when the police stepped in, the optics were no better: The Otpor members fled, and the opposition TV the next day showed pictures of the police “arresting” a barrel and loading it into the police van. The country sniggered at these pranks — and signed up for Otpor.

Rather than trying to avoid arrests, Otpor decided to provoke them and use them to the movement’s advantage. After a few months it became evident that while police would rough up Otpor members, torture was rare and few of them would even be kept overnight. When any Otpor member was arrested, the organization sent a noisy crowd to hang out on the street outside the police station. Detainees would emerge from the police station to find a pack of opposition journalists and a cheering crowd of friends. Young men competed to rack up the most arrests. If wearing Otpor’s signature fist-emblazoned black T-shirt made you an insider in the revolution, getting arrested made you a rock star. People who once thought of themselves as victims learned to think of themselves as heroes.

Two years after its founding, Otpor’s 11 members had become more than 70,000. “The signal thing they did that should never be lost is that they made it OK for Serbs to say publicly that the regime was not invincible, that many Serbs shared a sense that change could come,” said James O’Brien, the Clinton administration’s special envoy to the Balkans. By the time Milosevic ran for reelection as president of Yugoslavia in September 2000, Otpor’s prolonged protest campaign — and Milosevic’s attempts to suppress it — had eroded the president’s popularity and emboldened and helped to unify the opposition. When Milosevic refused to concede defeat to opposition candidate Vojislav Kostunica, Otpor’s example of disciplined nonviolence, along with its masses of activists, were crucial in convincing Serbia’s security forces to defy Milosevic’s orders to shoot at the protesters. On Oct. 7, the embattled president resigned.

The unthinkable had happened. For the young Serbs, the next step was figuring out how to export it.

The Battle of Towton

Tuesday, April 12th, 2011

When I started reading A Game of Thrones a few years ago, I couldn’t help but notice that Martin took some inspiration from the Wars of the Roses — which had inspired other notable works.

Recently The Economist discussed The Battle of Towton, a little-known but important battle from that era:

In a letter sent nine days after the battle George Neville, the then chancellor of England, wrote that 28,000 men died that day, a figure in accord with a letter sent by Edward to his mother. England’s total population at the time is thought not to have exceeded 3m people. George Goodwin, who has written a book on Towton to coincide with the battle’s 550th anniversary in 2011, reckons as many as 75,000 men, perhaps 10% of the country’s fighting-age population, took the field that day.

They had been dragged into conflict in various ways. Lacking a standing army, the royal claimants called on magnates and issued “commissions of array” to officers in the shires to raise men. Great lords on either side had followings known as “affinities”, comprising people on formal retainers as well as those under less rigid obligations. These soldiers would have been among the more experienced and better-equipped fighters that day (foreign mercenaries were there, too). Alongside them were people lower down the social pyramid, who may have been obliged to practise archery at the weekend as part of the village posse but were not as well trained. Among this confusion of soldiers and weaponry, almost certainly on the losing Lancastrian side, was Towton 25.

He gets his name from the order in which he was removed from the ground. In the summer of 1996 builders working at Towton Hall, about a mile away from the main battlefield, discovered a mass grave. Archaeologists from the University of Bradford eventually took charge of an excavation of almost 40 individuals, 28 of whom were complete skeletons. (Further bodies have subsequently been recovered from beneath the dining-room at Towton Hall, which must make for conversation, at least.) The skeletons had clearly been the victims of great violence. Many display the same frenzied wounding as Towton 25. “Imagine one of those movie scenes with people closing in on a cornered individual,” says Christopher Knüsel, one of the original team of archaeologists and now at the University of Exeter. “Usually the camera has to pan away because you cannot show some things. Here you see it.” The location of the bodies, and subsequent carbon-dating, linked them conclusively to the battle of Towton.
[...]
The men whose skeletons were unearthed at Towton were a diverse lot. Their ages at time of death ranged widely. It is easier to be precise about younger individuals, thanks to the predictable ways in which teeth develop and bones fuse during a person’s adolescence and 20s. The youngest occupants of the mass grave were around 17 years old; the oldest, Towton 16, was around 50. Their stature varies greatly, too. The men’s height ranges from 1.5-1.8 metres (just under five feet to just under six feet), with the older men, almost certainly experienced soldiers, being the tallest.

This physical diversity is unsurprising, given the disparate types of men who took the battlefield that day. Yet as a group the Towton men are a reminder that images of the medieval male as a homunculus with rotten teeth are well wide of the mark. The average medieval man stood 1.71 metres tall — just four centimetres shorter than a modern Englishman. “It is only in the Victorian era that people started to get very stunted,” says Mr Knüsel. Their health was generally good. Dietary isotopes from their knee-bones show that they ate pretty healthily. Sugar was not widely available at that time, so their teeth were strong, too.

Laid out on a laboratory bench in the University of Bradford’s archaeology department, the biggest of the soldiers still look burly (though their bones, without any collagen in them, are incredibly light to handle). They seem to have led active lives. Bone grows in response to strenuous muscular activity, particularly if exercise starts in childhood. For instance, the serving arm of a professional tennis player has as much as a third more bone in it than his non-dominant arm.

Some of the Towton men display the same type of unusual bone density. But it is distributed in a very unmodern way: their upper-arm bones are very well-developed towards the right shoulder and the left elbow. The medieval longbow, which placed huge stress on both the drawing arm and the arm that held the bow steady, may have been responsible. Towton 16 has something known as an avulsion fracture to his left elbow, a condition first clinically identified among young baseball players in America. This injury occurs only in adolescence, when the bones in the arm have not yet fully fused, and may have been caused by attempts to practise with an adult longbow. In 1420s England the teenage Towton 16 was suffering from Little Leaguer’s Elbow.
[...]
By looking at the different ways that bone fractures when it has fluids in it and when it has dried out, Ms Novak found that 27 of the 28 skulls she examined had suffered blows at the time of death. Not just one, either. Both Towton 16 and 25 were struck eight times and Towton 10 six times. Towton 32 suffered no fewer than 13 different blows to the head.

According to Graeme Rimer of the Royal Armouries, Britain’s arms museum, medieval weapons had the capacity to decapitate or amputate at a single stroke. “Given how much damage you can do with one blow, why land another 12?” he asks. There were signs of mutilation, too: marks on the left side of Towton 32’s head suggest that his ear had been sliced off.

The next task was to try to identify the weapons which might have done this damage. Ms Novak took a variety of medieval weapons from the collection of the Royal Armouries and poked them through pieces of acoustic ceiling tile to see what shape they made. Some of the matches were uncanny — the dagger that had to be twisted on the way out, the beak of a war hammer. The puzzling range of blunt, sharp and puncture wounds have their explanation in the lethal versatility of the poleaxe, with its bladed axe, top-spike and hammer (see picture).

Put all this together and two questions stand out: what had happened to the men’s helmets, and how could their assailants hit them so many times? In the press of battle, after all, you are unlikely to want to spend time and energy landing repeated blows.

At this distance any theories are likely to remain plausible rather than proven. But the likeliest explanation is that the Towton soldiers (or some of them, at least) were among the Lancastrian soldiers routed from the battlefield. The secret of success in medieval battle was to hold ranks, so that comrades on either side would still be protecting your flanks. That is particularly true given the steep ground shelving away from the plateau where the main battle was fought. “If you move, you lose,” says Mr Sutherland.

On the run from the battle, with Yorkist soldiers in pursuit (some of them doubtless on horseback), the men would have soon overheated. They may have removed their helmets as a result. Overhauled — perhaps in the vicinity of Towton Hall, which some think may then have been a Lancastrian billet — and disorientated, tired and outnumbered, their enemies would have had time to indulge in revenge. Even at this distance the violence is shocking. “It’s almost as if they were trying to remove their opponents’ identities,” says Mr Knüsel of the attackers’ savagery. Thanks to some unsuspecting builders and a team of archaeologists, they did not entirely succeed.

Anatomical Changes from Practice during Development

Tuesday, April 12th, 2011

Some types of expertise benefit from anatomical changes from practice during critical developmental periods:

For example, ballet dancers’ ability to turn out their feet, and baseball pitchers’ ability to stretch back with their throwing arm are linked to practice overload at around 8- to 11-years-of-age, when the children’s bones are in the process of being calcified (Ericsson & Lehmann, 1996).

More generally, early and extended training has been shown to change the cortical mapping of the brain area controlling fingers of string players (Elbert et al., 1995) and the flexibility of fingers (Ericsson & Lehmann, 1996). Also interesting is the recent finding that intense music practice influences the development of myelin around nerves in critical brain regions. The development of white matter (myelin) occurs in different brain regions at different ages (Bengtsson et al., 2005). Even the famous ability to name musical notes in isolation — ‘the gift for perfect pitch’ (Simonton, 2005, p. 312) — is linked to a very early developmental window of opportunity. It is most easily acquired between ages 3 and 5 years during early music instruction, when children encode stimuli in absolute terms (Levitin & Rogers, 2005). At older ages music students encode musical tones in relation to other tones and thus acquire relative pitch, finding it far more difficult to acquire absolute pitch.

Importantly, these differences in adult abilities are explained with critical periods, rather than with genetic differences between individuals. There are interesting examples of late starters, who attempt to attain the physical adaptations of the early starters but are not able to do so and where the training of the late-starting adults may lead to injuries (Pieper, 1998).