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Study: CT scans raise cancer risk

Millions of Americans, especially children, are needlessly getting dangerous radiation from "super X-rays" that raise the risk of cancer and are increasingly used to diagnose medical problems, a new report warns.

In a few decades, as many as 2 percent of all cancers in the United States might be due to radiation from CT scans given now, according to the authors of the report.

Some experts say that estimate is overly alarming. But they agree with the need to curb these tests particularly in children, who are more susceptible to radiation and more likely to develop cancer from it.

"There are some serious concerns about the methodology used," but the authors "have brought to attention some real serious potential public health issues," said Dr. Arl Van Moore, head of the American College of Radiology's board of chancellors.

The risk from a single CT, or computed tomography, scan to an individual is small. But "we are very concerned about the built-up public health risk over a long period of time," said Eric J. Hall, who wrote the report with fellow Columbia University medical physicist David J. Brenner.

It was published in Thursday's New England Journal of Medicine and paid for by federal grants.

The average American's total radiation exposure has nearly doubled since 1980, largely because of CT scans. Medical radiation now accounts for more than half of the population's total exposure; it used to be just one-sixth, and the top source was the normal background rate in the environment, from things like radon in soil and cosmic energy from the sun.

A previous study by the same scientists in 2001 led the federal Food and Drug Administration to recommend ways to limit scans and risks in children.

But CT use continued to soar. About 62 million scans were done in the U.S. last year, up from 3 million in 1980. More than 4 million were in children.

Since previous studies suggest that a third of all diagnostic tests are unnecessary, that means that 20 million adults and more than 1 million children getting CT scans are needlessly being put at risk, Brenner and Hall write.

Ultrasound and MRI, or magnetic resonance imaging, scans often are safer options that do not expose people to radiation, they contend.

CT scans became popular because they offer a quick, relatively cheap and painless way to get 3D pictures so detailed they give an almost surgical view into the body. Doctors use them to evaluate trauma, belly pain, seizures, chronic headaches, kidney stones and other woes, especially in busy emergency rooms. In kids, they are used to diagnose or rule out appendicitis.

But they put out a lot of radiation. A CT scan of the chest involves 10 to 15 millisieverts (a measure of dose) versus 0.01 to 0.15 for a regular chest X-ray, 3 for a mammogram and a mere 0.005 for a dental X-ray.

The dose depends on the type of machine and the person — obese people require more radiation than slim ones — and the risk accumulates over a lifetime.

"Medical care in this country is naturally so fragmented. Any one doctor is not going to be aware of the fact that a particular patient has had three or four CT scans at some point in the past," said Dr. Michael Lauer, prevention chief at the National Heart, Lung and Blood Institute.

People with chronic problems like kidney stones are likely to get too many scans, said Dr. Fred Mettler, radiology chief in the New Mexico Veterans Administration health care system.

"I've seen people who are 30 years old who have had at least 18 scans done," he said.

That puts them at risk of developing radiation-induced cancer, Brenner and Hall said. They base this on studies of thousands of Japanese atomic bomb survivors who had excess cancer risk after exposures of 50 to 150 millisieverts — the equivalent of several big CT scans.

"That's very controversial. There's a large portion of the medical physics community that would disagree with that" comparison, said Richard Morin, a medical physicist at the Mayo Clinic in Jacksonville, Fla. However, others defended the data, which has been widely cited in other radiation studies.

"It's the best evidence we've got" on cancer risks, Lauer said.

Dr. Robert Smith, the American Cancer Society's director of screening, said the authors' estimate that 2 percent of future cancers may be due to CT scans "seems high." But since cancers take 10 to 20 years to develop, "the ability to even observe that kind of an increase is going to be very difficult," he said.

The authors stressed that they were not trying to scare people who need CT scans away from having them. In most cases, the benefits exceed the risks, especially for diagnostic scans.

However, using the scans to screen people with no symptoms of illness — like screening smokers for signs of lung cancer — has not been shown to save lives and is not currently recommended.

Many groups also condemn whole-body scans, often peddled by private practitioners in shopping centers as peace of mind to the worried well. Many of these centers are not accredited by the College of Radiology; only a third of all places that do CT scans in the U.S. are, although insurers are starting to require it for reimbursement, Moore said.

Many CT centers also are set up for adults and rarely image children, who need adjustments to limit dose and radiation risk, said Dr. Alan Brody, a radiologist at Cincinnati Children's Hospital Medical Center who wrote a report on the topic. He said parents should seek a center that often handles children.

Both doctors and patients need to be more aware of radiation risks and discuss them openly, Brenner and Hall said.

"We were astonished to find, when we were researching materials for this paper, how many doctors, particularly emergency room physicians, really had no idea of the magnitude of the doses or the potential risks that were involved," Hall said.

Other studies found the opposite problem: Three out of 10 parents in one study insisted on CT scans instead of observing the child's condition for awhile even after they were told of the radiation risk, Brody said.

"This is what our patients want," and they expect fast answers from doctors, he said.

The pressure is greatest for ER doctors who "are in a bind ... they have all these patients stacked up" and need to make quick decisions, Mettler said.

Future generations of devices using less radiation should help alleviate the concern, but these mostly are directed at the emerging field of heart scans, Lauer said.

"When we order a CT scan it just doesn't seem like such a big deal" but it should be, he said. "The threshold for ordering these tests is low and it's getting lower and lower over time, which means that the risks become potentially all that more important." 

Photo
A doctor looks over a CT scan of a brain near the emergency room at the Childrens National Medical Center in Washington in this 2002 file photo. Millions of Americans, especially children, are needlessly getting dangerous.


PR

Drought Exacerbates Carbon Dioxide Problem

Droughts do more harm than just parching the land. They can also exacerbate rising carbon dioxide levels, government scientists have found.

In North America alone, human activity—from driving cars to generating power in factories—releases about two billion tons (1.85 billion metric tons) of carbon in the form of carbon dioxide every year. Natural carbon sinks such as forests, grasslands, crops and soil absorb about one-third of those emissions, scientists estimate.

But droughts seem to hamper the ability of these sinks to suck up the greenhouse gas. A new measurement system introduced by the National Oceanic and Atmospheric Administration, called CarbonTracker, has provided scientists with weekly observations of carbon dioxide exchange from 2000 to 2005.

The data, detailed in a new study in the Nov. 26 issue of the journal Proceedings of the National Academy of Sciences, showed that in 2002, when North America experienced one of the largest droughts in more than a century, the amount of carbon taken up by vegetation and soil plunged from 716 million tons to 363 million tons.

"Scientists often look at the role of greenhouse gases in producing climate extremes," said study leader Wouter Peters, affiliated with Wageninen University and Research Center in The Netherlands. "Here we show the reverse is also true. Climate extremes can have a major effect on the amount of carbon dioxide in Earth’s atmosphere."

Drought and other variations in a region's climate can change temperatures, rainfall, soil moisture and even the length of the growing season in that region. If less rain falls and soil moisture drops, plants may wither and die and so take up less carbon dioxide.

The connection between drought and increased carbon dioxide levels isn't unique to North America; the widespread drought and heat wave that struck Europe in 2003 left more than 500 million extra tons of carbon dioxide in the atmosphere that year, CarbonTracker showed. This problem could have consequences for efforts aimed at reducing greenhouse gas emissions.

"Disruptions to natural carbon uptake can have enormous environmental and economic effects, possibly even erasing efforts to reduce fossil fuel emissions in a given year," Peters said. 

 
On this map of North America, red areas denote reduced carbon dioxide absorption in the summer of 2002 with blue areas showing enhanced absorption.


Fake Photos Alter Real Memories

In 2003, Los Angeles Times photographer Brian Walski caused an uproar when it was discovered that his picture of a British soldier yelling at fleeing residents in Iraq, published prominently by many U.S. newspapers, had been altered.

Walski had combined two snapshots taken moments apart of the British soldier urging residents to take cover as Iraqi forces opened fire. This digital alteration is one of several in recent years to cast doubt on the old saying that the camera doesn't lie.

Some researchers are worried that digitally altered photos could alter our perceptions and memories of public events.

To test what effect doctored photos might have, researchers from the University of California, Irvine, and the University of Padua in Italy showed 299 people aged 19 to 84 either an actual photo or an altered photo of two historical events, the 1989 Tiananmen Square protest in Beijing and the 2003 anti-war protest in Rome.

The original Tiananmen Square image was altered to show a crowd watching at the sidelines as a lone man stands in front of a row of tanks. The Rome anti-war protest photograph was altered to show riot police and a menacing, masked protester among the crowd of demonstrators.

When answering questions about the events, the participants had differing recollections of what happened. Those who viewed the altered images of the Rome protest recalled the demonstration as violent and negative and recollected more physical confrontation and property damage than actually occurred.

Participants who viewed the doctored photos also said they were less inclined to take part in future protests, according to the study, detailed in the journal Applied Cognitive Psychology.

"It’s potentially a form of human engineering that could be applied to us against our knowledge and against our wishes, and we ought to be vigilant about it," said UC Irvine psychologist Elizabeth Loftus, who designed the study. "With the addition of a few little upsetting and arousing elements in the Rome protest photo, people remembered this peaceful protest as being more violent than it was, and as a society we have to figure how we can regulate this." 

 
Original photo of the Tianamen Square protest in Beijing (left) and the doctored photo of the event, with a crowd added (right). Credit: UCI

 
A photograph of a peaceful 2003 anti-war protest in Rome is doctored so that the added elements make viewers recall the event as more violent that it was.

Oddly, Hypocrisy Rooted in High Morals

Morally upstanding people are the do-gooders of society, right? Actually, a new study finds that a sense of moral superiority can lead to unethical acts, such as cheating. In fact, some of the best do-gooders can become the worst cheats.

Stop us if this sounds familiar.

When asked to describe themselves, most people typically will rattle off a list of physical features and activities (for example, "I do yoga" or "I'm a paralegal"). But some people have what scientists call a moral identity, in which the answer to the question would include phrases like "I am honest" and "I am a caring person."

Past research has suggested that people who describe themselves with words such as honest and generous are also more likely to engage in volunteer work and other socially responsible acts.

But often in life, the line between right and wrong becomes blurry, particularly when it comes to cheating on a test or in the workplace. For example, somebody could rationalize cheating on a test as a way of achieving their dream of becoming a doctor and helping people.

In the new study, detailed in the November issue of the Journal of Applied Psychology, researchers find that when this line between right and wrong is ambiguous among people who think of themselves as having high moral standards, the do-gooders can become the worst of cheaters.

The results recall the seeming disconnect between the words and actions of folks like televangelist and fraud convict Jim Bakker or admitted meth-buyer Ted Haggard, former president of the National Evangelical Association, an umbrella group representing some 45,000 churches.

"The principle we uncovered is that when faced with a moral decision, those with a strong moral identity choose their fate (for good or for bad) and then the moral identity drives them to pursue that fate to the extreme," said researcher Scott Reynolds of the University of Washington Business School in Seattle. "So it makes sense that this principle would help explain what makes the greatest of saints and the foulest of hypocrites."

Why cheat? Why not?

Why would a person who thinks of himself as honest cheat? The researchers suggest an "ethical person" could view cheating as an OK thing to do, justifying the act as a means to a moral end.

As Reynolds put it: "If I cheat, then I'll get into graduate school, and if I get into graduate school, then I can become a doctor and think about all the people I'm going to help when I'm a doctor."

A competitive playing field, whether at a university or business, can also motivate cheating behaviors.

"Cheating is a way to get ahead in a competitive environment where there are rewards for winning or getting ahead of others," said Daniel Kruger, an evolutionary psychologist at the University of Michigan, who was not involved in the current study. "It seems like there is an increasing desire and expectation in our society to 'be the best.'"

Even if a person doesn't justify his unethical behaviors, "cheating can save lots of time and energy and take advantage of the knowledge and reasoning of others who are more adept, but could be disastrous if one is caught," Kruger said. He added, "I am not surprised that some of the extreme examples of cheating—ripping the relevant pages out of library books so other students cannot see them—happen in intensely competitive environments, law school in this example [of ripping out book pages]."

Cheating basics

Reynolds and University of Washington colleague Tara Ceranic surveyed about 230 college students with an average age of 21 who were enrolled in an upper-level business course. The survey measured moral identity with 12 questions about the importance of certain characteristics, such as generosity, willingness to work hard, honesty and compassion, and whether things like clothing, books, activities and friends were associated with the moral characteristics.

Students were also asked whether they had engaged in each of 13 cheating behaviors, including using cheat sheets (crib notes), copying from another student and turning in work completed by someone else.

Overall, cheating was rampant.

  • More than 90 percent reported having committed at least one of the 13 cheating behaviors.
  • More than 55 percent reported saying nothing when they had benefited from an instructor's grading error.
  • Nearly 50 percent reported having inappropriately collaborated on an individual assignment.
  • Nearly 42 percent indicated copying from another student during a test.

Students who scored high on moral identity and also considered cheating to be morally wrong were the least likely to cheat. In contrast, the worst cheaters were the "moral" students who considered cheating to be an ethically justifiable behavior in certain situations.

"If they think it's wrong, they'll never do it," Reynolds told LiveScience. "If they think it's OK, they do it in spades."

The researchers found similar results when they surveyed 290 managers, asking them whether they had engaged in 17 workplace "no-no's," including using company services for personal use, padding an expense account and taking longer than necessary to do a job. The managers with moral identities were also most likely to engage in the sketchy office behavior.

"When people have a strong moral identity, they think of themselves as great moral people, their behavior tends to go to the extremes," Reynolds said.

Cheat-proof tactics

In order to encourage students and managers to forego cheating in exchange for ethical behaviors, Reynolds suggests ethics education. Classes, newsletters and other means of communication should help organizations to communicate which behaviors are morally acceptable and which are not.

The old-school method of rewards and punishments could help. "We learn through rewards and punishments so to the extent that schools crack down when they need to crack down, we'd all be better off," Reynolds said.

For managers recruiting new employees, just because a person identifies himself or herself as honest doesn't mean they won't cut corners.

"If you can recruit people with a moral identity and then train them appropriately, you'll get some of the best behavior you can imagine," Reynolds said.

 

Rock of Ages, Ages of Rock

On a muggy afternoon
in July, a group of geologists from around the country put on some bug spray and fanned out along one of Ohio’s richest fossil beds. The rock walls were slippery and steep at points, and some people came in their dress shoes straight from the conference that brought them together. But no one seemed daunted; when let loose on the rocks they behaved like children with a piñata, filling their pockets with local specimens and cooing over their treasure. “Ahh, that’s a beautiful brachiopod!” or “A fine trilobite! Let me see that.”
A brightly painted sign in the state park explained that 450 million years ago these ancient creatures lived at the bottom of a warm, shallow sea during the Ordovician period. But none of these geologists believed it. As young-earth creationists, they think the earth is about 8,000 years old, give or take a few thousand years. That’s about the amount of time conventional geology says it can take to form one inch of limestone.

Creationist ideas about geology tend to appeal to overly zealous amateurs, but this was a gathering of elites, with an impressive wall of diplomas among them (Harvard, U.C.L.A., the Universities of Virginia, Washington and Rhode Island). They had spent years studying the geologic timetable, but they remained nevertheless deeply committed to a different version of history. John Whitmore, a geologist from nearby Cedarville University who organized the field trip, stood in the middle of the fossil bed and summarized it for his son.

“Dad, how’d these fossils get here?” asked Jess, 7, looking up from his own Ziploc bag full of specimens.

Whitmore, who was wearing a suede cowboy hat, answered in a cowboy manner — laconic but certain.

“From the flood,” he said.

What was remarkable about the afternoon was not so much the fossils (the bed is well picked over) but the gathering itself, part of the First Conference on Creation Geology, held on the Cedarville campus. Creationist geologists are now numerous enough to fill a large meeting room and well educated enough to know that in rejecting the geologic timeline they are also essentially taking on the central tenets of the field. Any “evidence” presented at the conference pointing to a young earth would be no more convincing than voodoo or alchemy to mainstream geologists, who have used various radiometric-dating methods to establish that the earth is 4.6 billion years old. But the participants in the conference insist that their approach is scientifically valid. “We’re past the point of being critical of evolutionists,” Whitmore told me. “We’re trying to go out and make new discoveries and actually do science.”

Creationist geologists are thriving, paradoxically, at a moment when evangelicals are becoming more educated, more prosperous and more open to scientific progress. And though they are a lonely few among Christian academics, they have an influence far out of proportion to their numbers. They have just opened a state-of-the-art $27 million museum in Kentucky, and they dominate the Christian publishing industry, serving as the credentialed experts for the nearly half of Americans who believe in some version of a young earth. In a sense, they represent the fundamentalist avant-garde; unlike previous generations of conservative Christians, they don’t see the need to choose between mainstream science and Biblical literalism.

This creationist approach to science is actually a relatively modern phenomenon, only about 50 years old. When the state of Tennessee put the biology teacher John Scopes on trial for teaching evolution in the 1920s, the creationists did not have a single credentialed supporter. Their main champions were an expert on penmanship, a dropout from homeopathic school and a Canadian surgeon who was billed on his travels as “the greatest scientist in all the world.” William Jennings Bryan, noted prosecutor in the Scopes trial, was not overly concerned with the age of the earth; he equated six-day creationism with the flat-earth theory.

Then in 1961, John Whitcomb, a theologian, and Henry Morris, a hydraulic engineer from Texas, published “The Genesis Flood: The Biblical Record and Its Scientific Explanations.” The book revived a relatively obscure, century-old theory of Noah’s flood as the most violent catastrophe in earth history. The flood, they argued, warped the normal geological processes and caused rapid transformations. Water from the skies and from within the earth (“the floodgates of heaven”) slammed into the oceans, killing the sea creatures and covering the “high mountains,” as it says in Genesis. For months afterward, the planet convulsed with earthquakes, tsunamis and volcanoes. After a brief ice age, the earth became the ecosystem we know today. Continents shifted; the water receded; the animals left the ark and spread over the earth.

Until then fundamentalists had mostly avoided any close study of geology, because a literal reading of the Bible was too difficult to reconcile with the accepted age of the earth. But “The Genesis Flood” served as their version of “The Feminine Mystique,” a generational manifesto that liberated them to explore. In the decades since, a small band of geologists, including Whitmore, have set to work improving on the Morris-Whitcomb model using the modern tools of their field: close examination of rocks and fossils combined with computer models.

Now the movement can count hundreds of scientists with master’s or Ph.D. degrees in the sciences from respectable universities. The change started in part when Christian colleges that used to resist mainstream science started premed programs, which meant they needed trained biologists and chemists. Eventually they added courses in physics, chemistry and geology. Most geologists teaching at Christian colleges in the United States today say they do not believe in a young earth; they typically argue that a “day” in Genesis does not necessarily mean a literal 24-hour day, or that there could have been long gaps between the days. But the young-earthers treat the words of Genesis as irrefutable fact.

Their ideas are being showcased in the new Creation Museum in Petersburg, Ky., opened in May by a creationist group called Answers in Genesis, whose headquarters are nearby. With its wide-open spaces and interactive exhibits, the place feels like a slick museum of natural history, updated for the Hollywood age. Many of the exhibits were designed by Patrick Marsh, who helped create the “Jaws” and “King Kong” attractions at Universal Studios in Florida. Giant dinosaurs guard the courtyard entrance, promising fun and adventure. Inside, a replica of the ark leads you from seaboard to bottom deck, a rumbling theater replicates the flood, James Cameron-style. Lifelike models of Adam and Eve (who looks like the Brazilian supermodel Gisele Bündchen) frolic in a lush garden among the animals, including several dinosaurs.

The museum expected about 250,000 visitors in the first year. Instead, despite its $20 entry fee, it has had that many in six months, according to Michael Matthews, the museum’s content manager. Almost every day, minivans and buses from Christian schools fill the parking lot, sometimes after 10-hour road trips. The museum’s target group is the 45 percent of Americans who, for 25 years, have consistently agreed with the statement in a Gallup poll that “God created human beings pretty much in their present form at one time within the last 10,000 years or so.”

The museum sends the message that belief in a young earth is the only way to salvation. The failure to understand Genesis is literally “undermining the entire word of God,” Ken Ham, the founder of Answers in Genesis, says in a video. The collapse of Christianity believed to result from that failure is drawn out in a series of exhibits: school shootings, gay marriage, drugs, porn and pregnant teens. At the same time, it presents biblical literalism as perfectly defensible science. A fossil shows a perch eating a herring, evidence, they claim, of animals instantaneously trapped by catastrophic events after the flood. In a video, geologists use evidence from Mount St. Helens to show how a mud flow can cut a deep canyon in a single day. “This is what I see based on science,” said Andrew Snelling, one of the many creationist geologists at the conference in July who consulted with the museum.

At the conference, participants got together to tackle some difficult questions: How is radioisotope dating flawed? How was the Grand Canyon formed? If all those animals died in one cataclysmic event, why do their fossils appear in such distinct order? Their discussions recall a pre-Darwinian age, before science and faith became enemies. The old-earthers see their discipline as more pure than intelligent design; the intelligent-design people focus on a notion of a mystery “designer,” without specifying who that might be and what the mechanisms are. To the young-earth creationists, this is both unscientific and dubiously religious. “We don’t subscribe to this idea of the ‘God of gaps,’ meaning if you can’t explain something, then blame God,” Whitmore told me before describing a method that hardly seemed more scientific. “Instead, we think: ‘Here’s what the Bible says. Now let’s go to the rocks and see if we find the evidence for it.’ ”

The heads of all the leading scientific creationist institutes from several countries showed up for the Cedarville event, along with the movement’s other stars: John Baumgardner, a geophysicist who worked for 20 years at Los Alamos National Laboratory; Kurt Wise, who got his Ph.D. in paleontology from Harvard in the ’80s as a student of Stephen Jay Gould, the nation’s most famous opponent of creationism; and Marcus Ross, 31, the latest inductee into the movement, who got his Ph.D. in environmental science from the University of Rhode Island last summer.

Like any group of elites, they were snobs about their superior degrees. During lunch breaks or car rides, they traded jokes about the “vulgar creationists” and the “uneducated masses,” and, in their least Christian moments, the “idiots on the Web.” One leader of a creationist institute complained about all the cranks who call on the phone claiming to have seen dinosaurs or to have had a vision of Noah’s ark. (How Noah fit the entire animal kingdom onto the ark is a perennial obsession.)

Because they have been exposed to so much standard science, the educated creationists like Kurt Wise try not to allow themselves the blind spots of their less sophisticated relations. Some years ago, for instance, fellow creationists claimed to have found fossils of human bones in Pennsylvania coal deposits, which scientists date to millions of years before humans appeared. After examining them, Wise concluded that they were “not fossil material at all” but “inorganically precipitated iron siderite nodules.” Wise later pushed to get himself appointed as scientific adviser to the new creationist museum so he could “keep out the scientific garbage.”

In a presentation at the conference, Wise showed a slide of a fossil sequence that moved from reptile to mammal, with some transitional fossils in between. He veered suddenly from his usual hyperactive mode to contemplative. “It’s a pain in the neck,” he said. “It fits the evolutionary prediction quite well.” Wise and others have come up with various theories explaining how the flood could have produced such perfect order. Wise is refining a theory, for example, that the order reflects how far the animals lived from the shore, so those living farthest from the water show up last in the record. But they haven’t settled on anything yet.

“We have nothing to fear from data,” Ross told me. “If we’re afraid, it means we don’t trust God’s word.” The older generation of creationists “would come up with an explanation or a model and say, ‘This solves it!’ I’m a bit more cautious and at the same time more rigorous. We have lines of possibility that we continue to advance but at the same time we recognize that this is science, so the explanations are subject to change with new discoveries.”

As the latest recruit into a small elite, and with his clipped dark hair and goatee, Ross was the novelty at the conference. He grew up in Rhode Island, was an undergraduate at the University of Pennsylvania and got his Ph.D. under David Fastovsky, a well-known expert in dinosaur extinction at the University of Rhode Island. Fastovsky knew Ross was a young-earth creationist; they’d talked about it after his application came in. “I guess I thought of it as a little bit like Jews playing Wagner,” Fastovsky told me. “The science stands or falls, just like the music, regardless of the disposition of the scientist.” Ross subsequently wrote a 197-page dissertation about a marine reptile called a mosasaur, whose disappearance he tracked through the Cretaceous period, about 65 million years ago. Fastovsky described the paper as “utterly sound,” and the committee recommended very minimal edits.

At the conference I asked Ross whether he still believes what he wrote in his graduate thesis. His answer confirmed him as the product of the postmodern university, where truth is dependent on the framework: “Within the context of old age and evolutionary theory, yes. But if the parameter is different, portions of it could be completely in error.”

Outside school, Ross studied what he considered great breakthroughs in creation geology. In 1999, Ross came across John Baumgardner’s theory of catastrophic plate tectonics, which was proposed a few years earlier. The theory is the first attempt to describe the mechanism of the flood. It involves a fantastic “runaway” situation in which the ocean floor slides into the earth’s mantle in a matter of weeks and then hot rocks come to the surface of the ocean floor, causing ocean water to vaporize and rush out like a geyser (“the fountains of the great deep” described in Genesis). A computer model refining the theory purports to show an earth wobbling crazily on its axis as land masses come together and then break apart, forming the continents we have today.

“Until then, my options were pretty pathetic,” Ross said. Now he had something that “accounted for a large body of geological evidence,” proposed by a geophysicist trained at U.C.L.A. and supported by three other geology Ph.D.’s.

So which side did he choose?

“I have faith that the Bible is a true and accurate record of the earth,” he said. “I also entertain the possibility that I’m wrong. It would be cartoonish to say I don’t have doubts from time to time. Everybody has moments of doubt. But I can have those moments without my brain exploding.”

The new creationists are not likely to make much of a dent among secular scientists, who often just roll their eyes at the mention of flood geology. But they have become a burden to many geologists at Christian colleges around the country.

In recent years a number of Christian institutions have been undergoing what Alan Wolfe, a sociologist, calls “the opening of the evangelical mind.” Instead of teaching a fundamentalist world-view that is always at odds with secular academia, many evangelical colleges are easing their students into the mainstream.

The statement of faith for Wheaton College in Illinois, Billy Graham’s alma mater, for example, says that Scripture is “inerrant in the original writing” and that “God directly created Adam and Eve,” but when it comes to pinning down the age of the earth, the school balks. Wheaton has a strong geology department. Its professors argue that the Bible makes no specific mention of the age of the earth. They belong to groups like the Geological Society of America and wring their hands about the “geo-literacy” of the church. “Geology at Wheaton is presented and practiced much the same way as at secular universities,” the department chairman, Stephen Moshier, said in a recent talk. Other professors have issued long tracts comparing the various methods of radiometric dating and showing that they all agree: The earth is over four billion years old.

Most members of the American Scientific Affiliation, a collection of Christians with degrees in the sciences, qualify as old-earthers, according to Moshier. But the young-earthers have “a lot more influence,” he told me. They have “tremendous clout” with Christian publishers and are “very, very successful at getting their word out,” he said. “I know so many Christians who have tried to write books from a different perspective and been rejected.”

Marcus Ross, meanwhile, is thriving in his teaching job at Liberty University in Lynchburg, Va., founded by Jerry Falwell in 1971. Like many Christian colleges, Liberty is expanding rapidly to keep up with growing demand; the school adds 800 students a year, and now has a total of 10,000 on campus and 18,000 more distance-learning students. Each semester, Ross teaches a huge, mandatory survey course called History of Life. Most kids in the class are creationists, but Ross finds gaps in their world-view. His aim is to make their creationist logic more consistent, and his surveys show that he succeeds. At the beginning of the class, only 54 percent of students say the age of the earth is less than 10,000 years. By the end, it’s 87 percent. The biggest shift? Did dinosaurs and man live at the same time? That one moves to 80 percent from 40.

These numbers make Moshier cringe. “It can get so frustrating,” he said. “Many of us at Christian colleges really grieve at what a problem this young-earth creationism makes for the Christian witness. It’s almost like they’re adding another thing you have to believe to become a Christian. It’s like saying, You have to believe the world is flat to be a Christian, and that’s absolutely unreasonable.”

Given the difficulty of their intellectual enterprise, the creationist geologists often have a story about the time they nearly gave it up. For Wise the crisis hit when he was a sophomore in high school. He was already an avid fossil collector who dreamed “an unattainable dream” of going to Harvard to study paleontology and then to teach at a big university. But as he told a friend, he couldn’t reconcile the geologic ages with what he read in his Bible. So he set about figuring this out: every night, for months, he cut out every verse of the Bible he’d have to reject to believe in evolution. “I dreaded the impending end,” he writes in a collection of essays called “In Six Days: Why 50 Scientists Choose to Believe in Creation.” “All that I loved to do was involved with some aspect of science.”

When he was done, he tried to pick up what was left. But he found it impossible to do that without the Bible being “rent in two,” he writes. “Either the Scripture was true and evolution was wrong or evolution was true and I must toss out the Bible.” In the end, he kept his Bible and achieved his unattainable dream. But it left him in a strange, vulnerable place. “If all the evidence in the universe turned against creationism, I would be the first to admit it, but I would still be a creationist because that is what the Word of God seems to indicate. Here I must stand.”

In “The God Delusion,” Richard Dawkins, the evolutionary biologist and author, presents Wise as an Othello figure, destroyed by his own convictions. “The wound, to his career,” Dawkins writes, “and his life’s happiness, was self-inflicted, so unnecessary, so easy to escape. All he had to do was toss out the Bible. Or interpret it symbolically, or allegorically, as the theologians do. Instead, he did the fundamentalist thing and tossed out science, evidence and reason, along with all his dreams and hopes.”

If Wise still has doubts, or unhappiness, he has learned to put them aside. When consulting for the Creation Museum, he considered his most important duty to be presenting a “coherent story line about the earth’s history,” he said. “Even if it’s wrong, it’s a starting point. We use coherence as a criteria. It ought to fit together not as a set of random processes but something coherent orchestrated by God. And not just coherent but spine-tingling. God is behind this story. I can know it as a single story, and the story can be understood, and the story can be spine tingling. There’s a Whoa! factor. And it’s there from the first verse: The Lord God is One.” 

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