Thursday, December 30, 2010

A kind of immortality

It is impossible to think about one of the most important tools in medicine - the culture and study of human cells - without knowing about Henrietta Lacks, a poor, illiterate black woman who died of cervical cancer a week after her 31st birthday nearly 60 years ago.

I've known about Rebecca Skloot's book, "The Immortal Life of Henrietta Lacks," for many months, but it was only this week that I got around to buying a copy. I'm an idiot for waiting so long. It's one of the very best books of 2010, with stunningly moving writing that offers something for everyone - the science of cell cultures, the stumbling growth of medical ethics, race relations over the past 60 years, and the personal tale the lives of Henrietta's children and grandchildren. Let's add the author's long battle to win their trust and respect.

Shortly before Henrietta died doctors at Johns Hopkins operated to insert packets of radiation. In the process, without her knowledge or consent, they took samples of a tumor, hoping to get cells they could keep alive.

Her cancer cells not only thrived, but multiplied like lightning. If you've ever had a polio vaccine, thank Henrietta's cells - code-named HeLa - for showing the way. In fact, they've revolutionized the field. They've participated in atomic bomb tests to examine the effect of radiation on cells. They've been to the moon to study low gravity's effect. They've help lead to big advances in gene mapping, in vitro fertilization, and cloning.

They've also become a multi-million-dollar industry - not one dollar of which ever found its way to Henrietta's family, which knew nothing about HeLa for more than 20 years.

Skloot, an award-winning science writer, knew that this story required far more than science. It's a wonderful book. I'll never think of those vaccine-laden sugar cubes that we kids lined up to swallow in the early 1950s in quite the same way.

Tuesday, December 28, 2010

The start of something big

On some level, every generation of young people thinks it invented sex. (This is SO cool - it MUST be new!) In reality, of course, they know the business of internal fertilization - as opposed to spreading one's eggs on the seafloor for subsequent fertilization by males - has been around a long time. But just how long?

Until very recently, scientists thought our modern form of sexual intercourse was invented by a type of fish that includes early sharks roughly 350 million years ago. Now, however, new fossil study has revealed that copulation was brought into the world by primitive fish called placoderms ("plated skin"), armored creatures with backbones and jaws. They may have been ugly, but they invented the deed at least 25 million years earlier.

This leap back in time apparently has great significance for the study of evolution, but we're interested because placederms are directly on the long line leading to creatures with four limbs, including, eventually, humans.

And if humans are good at anything, it's you know what.

That proficiency took a long time to translate into significant population growth. Warfare, famine and especially disease kept our numbers down. It was one thing to make babies, but qute another to keep them alive to adulthood. Then, a few hundred years ago, all that quickly changed.

And, despite a general slowdown in women's birth rates, late in 2011 the Earth will reach a new milestone: a population of 7 billion souls. According to the UN Population Division, that number is projected to reach 9 billion by 2045.

Those ugly little placoderms had no idea what they'd done.

Monday, December 27, 2010

The glow of cigarettes

Since I quit smoking seven or eight years ago, I've tried not to turn into one of those post-smoker fanatics, pounding on tables and proclaiming: "Tobacco is the Devil and cigarette-company executives are his minions!"

It's been tough, however, given the revelations that keep popping up about what those executives knew, when they knew it, and how little they gave a damn.

For example, I just learned (from an article in the current Scientific American) that each of the almost six trillion cigarettes smoked each year contains a small amount of the uranium isotope polonium 210 (mostly from the phosphate rock from which fertilizer is made). It adds up to the equivalent radiation dosage of 300 chest x-rays a year for a person who smokes a pack and a half a day.

Polonium isn't the worst carcinogen in tobacco smoke, but it no doubt kills thousands of smokers a year. The tobacco industry has known about it for decades, and has come up with a variety of methods that could virtually eliminate the danger. But it was decided that "Removal of these materials would have no commercial advantage."

Grr. I'm looking around for a table to pound. But here is some good news. In June, 2009, President Obama signed into law an act that for the first time brings tobacco under the jurisdiction of the Food and Drug Administration. Requiring the industry to remove radiation from its tobacco products sounds like an obvious place to start.

Friday, December 24, 2010

Animals and math

Stories keep coming along about animals being better at mathematical computation than humans are. Many such stories at least are of scientific interest (with exceptions, such as the story about octopuses' knowledge of soccer), but they generally can be explained in other ways.

For instance, bees that seem to find the shortest path between many flowers in a meadow are said to have powers of calculation that far surpass our own. This is nothing more than a guess. To determine if a bee's path is optimal, you would have to measure all possible paths. Nobody's done that, or likely ever will. To suggest that bees have invented a general algorithm for picking the shortest path is a bit ridiculous - such tasks are so complex that they fall into a class of virtually unsolvable problems called NP-hard. Bees have evolved to be good at what they do, but they surely aren't doing math.

Another story asserts that pigeons are better than humans at "getting" our old friend the Monte Hall Problem. (Recall that a prize hides behind one of three doors. The contestant picks one door, and thus has a one-third chance of winning the prize. The game host then opens one of the remaining two doors, revealing no prize. Should the contestant switch to the remaining closed door? Yes. While his first choice still has that one-third chance, the remaining closed door now has a two-thirds chance of winning the prize.)

People are bad at this. In a recent study, even after playing multiple times (ample time to see that switching doubles one's chance of winning), most people switched only two-thirds of the time. It took only a few tries for pigeons to learn to switch every time.

Does this mean that pigeons are making some kind of statistical analysis? Are they thinking about the odds? Nope. They're just good observers who follow the evidence.

People, on the contrary, think too much. They overanalze, and get themselves all confused.

Thursday, December 23, 2010

Big findings, subtle flaws

Most of us put great weight on scientific consensus. When the results of peer-reviewed experiments gain general acceptance, it would be silly to doubt.

Unfortunately, it is becoming harder to keep the faith when results get harder to replicate as time goes by. The reason? Blame the human factor.

Let's take a fanciful example. You're a research biologist with a "brilliant" idea: red ants are "red" because back in their evolutionary history their main preditors were colr blind! Red and green looked the same to them!

You obtain grants and embark on experiments. Your grad students return with reams of data. Are you going to pick and choose between the data to confirm your hypothesis? Of course not, you're no fraud! But there still are subjective, delicate decisions to make regarding exactly which data to report. And, after all, you do hope for positive results - results more likely to be published in leading journals.

In recent years, attempts to replicate initial findings are tending to fail. For instance, the therapeutic value of certain new antipsychotic drugs seems to be waning. A study showing a srong correlation between bodily symmetry in animals and their reproductive success seems to be falling apart. A finding - already in the textbooks - that describing a face doesn't help us remember it may be true, but it is getting harder and harder to prove.

Chance plays a role in all this, of course, but subtle selectivity seems to be a big part of the story. This is unconscious - not fraud. Australian scientist Leigh Simmons (quoted by Jonah Lehrer in a recent New Yorker) put it this way: "The act of measurement is going to be vulnerable to all sorts of perception biases. That's not a cynical statement. That's just the way humans work."

Monday, December 20, 2010

An energy dilemma

Is increasing energy efficiency a bad thing? Well, maybe so.

In his article in the current New Yorker, author David Owen says the question was first raised 150 years ago. The 29-year-old British economist Willam Jevons concluded that more economical use of fuel results not in diminished consumption but an overall increase.

At the time, Great Britain was the world's leading industrial power, but its coal reserves were running out. Jevons said efforts to increase coal-burning efficiency would only backfire. As an example, he focused on the British iron industry. If a new process could produce iron with less coal, profits would rise, stimulating construction of new blast furnaces. Coal use at the increased number of furnaces would more than make up for the diminished consumption of each of them.

We no longer live in the Industrial Revolution, but similar examples still abound. The efficiency of refrigeration and air conditioning has improved greatly over the past half century, but their spread throughout society has meant that their overall energy use has grown far more. Cars have become much better at using fuel economically. But rather than fall, fuel consumption keeps rising. Whenever we save energy, we find more and more ways to use what we saved. Our standard of living goes up, but so does our energy use.

Those who downplay the Jevons effect believe that, in the end, it has little applicability in the modern world. And they raise this rather absurd corollary - if our energy use were to become less efficient, does that mean consumption would decrease?

So, is efficiency a bad thing? Well, maybe.

Sunday, December 19, 2010

Tragedy of the commons

Most of us have heard the story of the "tragedy of the commons." But have we heard the ecological version, or the ideological one?

The basic yarn posits a pasture used in common by herdsmen for their mutual benefit. But eventually, as people keep introducing more cattle, the pasture is degraded by overgrazing. People can't help trying to maximize their own wealth, even when it becomes clear that their individual actions are destroying the very pasture they all depend on.

Conservatives like to give the story an anti-socialism slant, saying that it proves the futility of collective ownership. Only individuals who own their land will take care of it properly.

This version appears not to be true. If it were, how could so many Middle-Ages collectives have succeeded for so many hundreds of years? There is indirect evidence in the historical record that success was the norm: Records of civil lawsuits contain almost no evidence that people were sued for damaging the commons by overgrazing. It seems likely that local ordinances - and a strong dose of peer pressure - kept greedy herdsmen in line.

Of course, the metaphor of the commons remains of vital ecological importance. I don't think I need to belabor all the ways that the Earth is under threat. Think of the commons not as a small pasture, but as the whole planet itself. And remember what Professor Eric G. Strauss of Boston College likes to point out: Around 1990, humans exceeded the capacity of Earth to support the demands we place on it.

Friday, December 17, 2010

Princess Leia

When the first Star Wars movie came out, I already was a bit too long in the tooth to fully embrace the Force. But for a time my son, 6 or 7 back then, fell deeply into a land of long ago and far away. He'd spend hours with his action figures - Luke Skywalker, Hans Solo, Darth Vader, Chewbacca and the rest - oblivious to the grown-up world.

But I wasn't completely immune. After all, there was Princess Leia. In her white dress. (Carrie Fisher recalls that when she first modeled the outfit for director George Lucas, he told her to lose the bra. "They don't wear underwear in space," Lucas said.

I took an interest in her career, and when HBO recently aired a feature-length movie of her one-woman production - "Wishful Drinking" - I made it a point to tune in. It's an excellent show, filled with powerful and gleeful wit along with some serious dish on her skirt-chasing father, Eddie Fisher, and her off-kilter mother, Debbie Reynolds.

It would be easy to joke about the poor little rich girl, but Fisher has had to cope with some big problems - not only her parents and her addictions to drugs and alcohol, but the bipolar disorder first diagnosed when she was a teenager. (At one point, she says, she was "invited" to a mental hospital. "You don't want to be rude. Right? So you go."

That kind of humor pervades the show. For instance, she described the end of her parents' marriage after the the death of their friend, Mike Todd, Elizabeth Taylor's husband: "Naturally my father flew to Elizabeth's side, gradually making his way, slowly, to her front." On her mother's fame: "She is literally an icon - a gay icon, but you take your iconic stature where you can find it."

Now in her mid-fifties, she says she recently Googled herself and found this posting: "WTF happened to Carrie Fisher? She used to be so hot. Now she looks like Elton John."

"Wishful Drinking" is a fun refusal by Fisher to take herself or her family too seriously, and it is welcome evidence that damaged people - even Princess Leia - can pull things together.

Tuesday, December 14, 2010

Taking scalps

During the War of 1812, America soldiers' greatest fear was being massacred, hacked to pieces and scalped by Indians fighting with the British. The sight and sound of war-painted, whooping warriors often was enough to send them into flight.

On May 29, 1813, British naval officer James Richardson watched as first one and then another boatload of American soldiers rowed toward his fleet on Lake Ontario, whitle flag flying. These 115 well-armed Americans were terrified of Indians on shore, and chose to surrender rather than fight them - all 36 warriors.

Richardson said the surrender can be explained by tales of Indian atrocities in the mouths of all mothers and nurses.

Americans blamed the British for spurring the Indians on. In Congress, Henry Clay refuted Federalist claims that Canadians were innocent. "Canada innocent? Canada unoffending? Is it not in Canada that the tomahawk of the savage had been molded into its death-like form?

The British, in turn, valued the Indians precisely because they scared the poop out of Americans. But they argued that Americans were hardly innocent. When an American general rebuked a british officer for the Indians' conduct, he reported that the officer cited as justification "that our government would send the Kentuckians into Canada."

A British sargeant reported that "These Kentucky men are wretches ... served out with blankets like the Indians, with a long knife and other barbarous articles ... After engagements they scallop the killed and wounded that could not get out of the way."

For what it's worth, it was an American who took the first scalp in the War of 1812. On July 29, 1812, Capt. William McCulloch killed and scalped a Menominee warrior, outraging the Menominee who had promised the British they would refain from taking scalps. Maybe it was a harsh sort of justice when, 10 days later, McCulloch fell into an ambush and lost his own scalp.

Sunday, December 12, 2010

Night thoughts

I had been having night thoughts anyway (albeit on a cold, cloudy Sunday afternoon) when I picked up the current New Yorker off the floor beside my chair and read an absolutely stunning essay by Joyce Carol Oates about the death of her husband of nearly 50 years.

As you would expect, Oates' piece is personal writing at its best. She describes how her robust if elderly husband, Raymond Smith, was hospitalized for an apparent case of pneumonia before succumbing a week later to raging bacteriological infections in his lungs. Interspersed with wise reflections about the nature of marriage, her memoir is a record of terror, wild hope, and ultimate despair. It is well worth the price of the Dec. 13 New Yorker.

As it happened, those night thoughts of mine had involved a similar topic. Oates spent most of her waking hours during her husband's last week at his bedside. When my Dad died - while my mother was home packing to stay with him at the hospice - I was 1,200 miles away. When, years later, my mother died of heart failure at 89, I was 1,800 miles away.

According to long tradition, a family gathers at a death bed to see a loved one off. The recent dispersal of family members across the country often makes that impossible. That last outpouring of feeling for the dying must be done from afar, and after the fact.

It can be suggested that, given what little we know of a dying person's last hours, the presence of family at the end may not really matter. It also can be said that, given the hopelessness and inevitability of the outcome, such a gathering is somehow futile. It even can be said that I was lucky to be 1,800 miles away.

Maybe. So why don't I feel lucky?

Friday, December 10, 2010

Early politics

After taking a break from history, I'm back reading Alan Tylor's "The Civil War of 1812." It didn't take long to find an analog to the deeply divided politics of today.

It was clear that by declaring and then winning the war, Republicans hoped to finally do in the Federalists. But for many, the passions of the day didn't want to wait that long. Thomas Jefferson, for instance, for instance, suggested that mobs armed with tar and feathers would intimidate Federalists in the South. In the North, where Federalists were more numerous, he implied the leaders should be hanged and their property confiscated.

Passions peaked in Baltimore, where shortly after the declaration of war a mob of hundreds attacked the office of a Federalist newspaper. The Federalists inside surrendered to city officials, who put them in jail for their safety. No luck. The next day a mob shouting "kill the tories" broke into the jail and attacked and tortured those who had been defending the newspaper. One died of a stab wound to the chest, 11 others suffered crippling injuries while the authorities refused to intervene. Rioters sang, "We'll feather and tar ev're d(amne)d British tory/And that is the way for American glory."

This sort of thing was the nightmare of the founders, who had especially feared political parties, or "factions," as a basic threat to the new republic. In their own way, Republicans agreed. Said Jefferson, "I will not say our party, the term is false and degrading, but our nation will be undone. For the Republican are the nation."

Thursday, December 9, 2010

Through a scanner, weakly

The recent flap over possible danger from airport body scanners - like the ongoing concern about cell phone radiation - demonstrates that for most Americans, radiation is scary, and that's all you need to know.

The appropriate meansurement for X-rays' impact on people is the amount of energy the rays contain. The unit used is the millirem, or mrem. According to international standards, 5,000 mrem per year is the maximum dose permitted for those who work with or around radioactive material. For the rest of us, the average yearly exposure is 620 mrem - most from outer space (from the sun, black holes, and supernovae) - and about 10 percent from medical procedures and other earthly causes.

Radiation exposure from airport full-body scanners is incredibly weak: about 0.01 mrem. After all, unlike medical X-rays, the scanners don't needd to look into your body - just through your clothes. By contrast, at 0.5 mrem, a dental X-ray is 50 times more powerful.

Here are some other figures, from data in the latest Newsweek magazine: 40 mrem for a mammogram, 50 mrem a year if you live in Denver, and 200 mrem a year from radon in the average home. It takes 100,000 mrem to get radiation sickness.

Worry about displaying your imperfections in an airport scanner if you must, but don't sweat the X-rays.

Tuesday, December 7, 2010

As with all surgery, side effects can occur

Hey, guys ... frustrated by the grim fact that women outlive men by an average of five to six years? That by age 85 there are roughly six women for every four men? That by age 100 the ratio is more than two to one?

What's the reason for this outrage? It appears that evolution is to blame. After all, evolution is a lot more interested in our offspring than it is about us. And healthy offspring need healthy moms. If the female body is weakened, reproduction is threatened. So gals get more maintenance - and apparently that early better health pays off in a longer lifespan.

Guys, on the other hand, while important to the wellbeing of their kids, don't do the womb thing. They don't do the suckle thing. No special maintenance for them.

In addition, it's been shown that, from an evolutionary point of view, the factors in males that lead to mating success aren't drivers of longevity. In fact, ligh levels of testosterone are quite bad for long-term survival.

The historical record doesn't show us whether eunuchs outlived normal healthy men, but there are recent studies that suggest they do. Not too long ago, castration of men in institutions for the mentally ill was surprisingly common. In a study of several hundred men at an unamed institution in Kansas, castrated men were shown to have lived 14 years long than those who were intact.

Ask your doctor if castration is right for you.

Sunday, December 5, 2010

Grow-up time?

Most scientists have long taken for granted that there had to be a multitude of alien civilizations out in our vast galaxy. Among so many stars, how could there not be? But of late, many scientists are starting to wonder: Is the Earth it?

Consider: The Earth is in the right 5 percent or so of the galaxy. Too far out, there's insufficient heavy elements, like the radioactive material that keeps continental plates moving and alive with energy. Too far in, it's a madhouse of dangerously close stars, a constant bombardment of comets and rocks, and fierce radiation. Also, our sun is just the right size. Stars that are too big don't last long enough to nurture life, stars that are too small (which are most of them) emit lower energy and create a habitable zone that's too close, resulting planets tidally locked so only one side always faces the sun. In addition, the earth is lucky in its neighbors. For instance, Jupiter is just in the right place and just the right size to steer most meteors and comets away. Meanwhile, our Moon is just the right size and in the right position to act as a gyroscope, minimizing changes in the tilt of the Earth's axis.

Add all the wondrously complex details that keep the planet alive - the rock cycle, the water cycle, the carbon cycle, and so on. The Earth, created with precisely the elements it needed, might exist despite overwhelming odds against it. Our planet might be a very special place indeed.

Do we treat it that way? Afraid not. Each year we lose about 70 gigatons of precious topsoil to the sea. We've filled in important wetlands. In the U.S. we've paved an area greater than the state of Ohio.

This is not to mention the huge and increasing changes we've made to the atmosphere, and all the extinctions we've caused in the biosphere. Geological eras are based on mass extinctions. All by ourselves, we've erased enough species to put paid to the current Cenozoic era - a 65-million-year era of time is crashing to an end.

Professor Michael E. Wysession of Washington University in Lt. Louis reminds us that humans are new to all this, and we're bound to make mistakes. He likens us to children.

Children grow up. Will we?

Friday, December 3, 2010

Global warming can be cool

These days, many people who hear the term "global warming" tend to wrinkle their noses and launch a lecture on responsibility. Of course, rapid human-caused climate change would be bad news for billions of people. But generally, global warming saves our butt every day. And, between 800 and 600 million years ago, runaway warming has cut short a particularly nasty sort of climate change: Snowball Earth.

Greenhouse gasses in the atmosphere - water vapor, carbon dioxide, ozone and methane - let sunlight pass on down to heat up the surface, but when the same amount of heat is reflected back at infrared frequencies, the gasses gobble it up and send much of it right back down to Earth. Be glad of this. Without that heat, the Earth would be too cold for liquid water to exist.

There is good geological evidence of several episodes of Snowball Earth - a time of cold and runaway glaciation that covered not only the continents with ice, but may well have frozen the entire surface of the oceans. Such episodes haven't happened since about 600 million years ago, perhaps because life forms like worms in marine sediments have churned up the seafloor, preventing the squestering of carbon and keeping it free to do its greenouse thing. (It is no surprise that fossiles of multicellular creatures don't exist until after this period.)

But how come the planet didn't just stay frozen? One leading theory is that as ice piled up, ocean levels dropped significantly. Seafloor, much of which lies atop huge deposits of methane, was exposed to erosion. Before long, methane (21 times as efficient, greenhousewise, as carbon dioxide) was streaming into the atmosphere. Runaway warming counteracted the runaway freezing.

This is not to say that humans ought to be messing with a planetary feedback system that's worked for billions of years. But think of global warming every time you enjoy a cool drink of water.