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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.” 

PR

Small World: Quantum Identity Crisis Observed

A quantum enigma has been put to the test once again, but this time physicists have made the experiment smaller than it has ever been.

The classic double-slit experiment tests the behavior of light, electrons, atoms and some molecules as both particle-like and wave-like, a mysterious duality that has intrigued and puzzled scientists for more than a century.

Light or electrons are aimed at a solid plate with two parallel cuts in it, offering two choices: go through the slit on the left or the slit on the right. Subatomic particles will sometimes break the rules and go through both slits, just as a wave would.

The most bizarre aspect of this particle-wave duality is that it depends on how much an observer pays attention. The more carefully the observer measures whether it was the left or right slit, the more the object in question chooses a single slit, just as a particle would.

Now an international team of scientists has exhibited this quantum identity crisis using a single hydrogen molecule as their lab equipment.

In this case, an incoming X-ray beam strikes the hydrogen molecule, thereby liberating the two electrons that typically buzz around the molecule's two central nuclei. But before these electrons shoot off into the surrounding space, they make a quick pass by one of the nuclei, which act like left and right slits.

The researchers concentrated on the "fast electron" that carried away the majority of the energy. As expected, the fast electron acted sometimes like a wave and sometimes like a particle.

Interestingly, this behavior depended on the other "slow electron," which interacted very slightly with the fast electron and in so doing played the part of the "observer."

If the slow electron had little energy, it had trouble measuring the fast electron's movement. As a consequence, the fast electron went through both slits like a wave. But if the slow electron had more energy, it got a good look at the fast electron, which responded by choosing one slit like a particle.

The results, detailed in the Nov. 9 issue of the journal Science, give some insight into how a future quantum computer might work as it relies on the phenomena of "superposition" and "entanglement" to perform operations on data stored in units called quantum bits.  

Scientists find fossil of enormous bug

This was a bug you couldn't swat and definitely couldn't step on. British scientists have stumbled across a fossilized claw, part of an ancient sea scorpion, that is of such large proportion it would make the entire creature the biggest bug ever.

How big? Bigger than you, and at 8 feet long as big as some Smart cars.

The discovery in 390-million-year-old rocks suggests that spiders, insects, crabs and similar creatures were far larger in the past than previously thought, said Simon Braddy, a University of Bristol paleontologist and one of the study's three authors.

"This is an amazing discovery," he said Tuesday.

"We have known for some time that the fossil record yields monster millipedes, super-sized scorpions, colossal cockroaches, and jumbo dragonflies. But we never realized until now just how big some of these ancient creepy-crawlies were," he said.

The research found a type of sea scorpion that was almost half a yard longer than previous estimates and the largest one ever to have evolved.

The study, published online Tuesday in the Royal Society's journal Biology Letters, means that before this sea scorpion became extinct it was much longer than today's average man is tall.

Prof. Jeorg W. Schneider, a paleontologist at Freiberg Mining Academy in southeastern Germany, said the study provides valuable new information about "the last of the giant scorpions."

Schneider, who was not involved in the study, said these scorpions "were dominant for millions of years because they didn't have natural enemies. Eventually they were wiped out by large fish with jaws and teeth."

Braddy's partner paleontologist Markus Poschmann found the claw fossil several years ago in a quarry near Prum, Germany, that probably had once been an ancient estuary or swamp.

"I was loosening pieces of rock with a hammer and chisel when I suddenly realized there was a dark patch of organic matter on a freshly removed slab. After some cleaning I could identify this as a small part of a large claw," said Poschmann, another author of the study.

"Although I did not know if it was more complete or not, I decided to try and get it out. The pieces had to be cleaned separately, dried, and then glued back together. It was then put into a white plaster jacket to stabilize it," he said.

Eurypterids, or ancient sea scorpions, are believed to be the extinct aquatic ancestors of today's scorpions and possibly all arachnids, a class of joint-legged, invertebrate animals, including spiders, scorpions, mites and ticks.

Braddy said the fossil was from a Jaekelopterus Rhenaniae, a kind of scorpion that lived only in Germany for about 10 million years, about 400 million years ago.

He said some geologists believe that gigantic sea scorpions evolved due to higher levels of oxygen in the atmosphere in the past. Others suspect they evolved in an "arms race" alongside their likely prey, fish that had armor on their outer bodies.

Braddy said the sea scorpions also were cannibals that fought and ate one other, so it helped to be as big as they could be.

"The competition between this scorpion and its prey was probably like a nuclear standoff, an effort to have the biggest weapon," he said. "Hundreds of millions of years ago, these sea scorpions had the upper hand over vertebrates — backboned animals like ourselves."

That competition ended long ago.

But the next time you swat a fly, or squish a spider at home, Braddy said, try to "think about the insects that lived long ago. You wouldn't want to swat one of those." 

This is a computer generated image issued by the University of Bristol in England released on Tuesday Nov. 20,  2007 showing a size comparison between a human an ancient sea scorpion. A fossil found in Germany indicates the ancient sea scorpion was once 2.5 metres (8 feet) long, making it the biggest bug ever known to  have existed. (AP Photo/University of Bristol, HO)

This is a computer generated image issued by the University of Bristol in England released on Tuesday Nov. 20, 2007 showing a size comparison between a human an ancient sea scorpion. A fossil found in Germany indicates...

 

Is Disease "Inheritance" More Random than Once Thought?

Random and frequent cellular deactivation of one of two gene copies could potentially change a genetic outcome 

purple genome with one gold gene

GOLD MARKS THE SPOT: Random inactivation of one of the two copies of genes passed on by parents is a more common occurrence than previously thought.

New research shows that cells often randomly deactivate one of a pair of gene copies or alleles, one of which they get from mom, the other from dad. This inactivation may potentially help explain why some children in a family may exhibit certain heritable disorders, whereas others do not.

Researchers at Massachusetts General Hospital (MGH) in Boston found that such disruptions may take place in as many as 1,000 genes in the autosomal genome (the part of our genetic repertoire that excludes sex cells), leading to different outcomes in the structures and levels of the proteins coded by these genes. These arbitrary alterations may, in some cases, clear a pathway for certain diseases such as Alzheimer's to manifest themselves.

"The general principle is that when a gene is turned on by a given cell or cell type that both alleles get expressed," says Harvard Medical School's Andrew Chess, a associate professor of medicine at MGH's Center for Human Genetic Research and co-author of the new study published in Science. "We've now found a large number of examples of an exception to that."

The finding could speak to more heterogeneity between individuals than can be accounted for by basic genetics. Though Chess and his colleagues do not know the mechanism by which alleles are silenced, the discovery that these events—called random monoallelic expression—occur so frequently suggests that epigenetic effects (influences on the activity of a gene that are not due directly to DNA mutations) may play a much more significant role in the development of some human diseases than previously believed.

Occurrences of allele inactivation are not new to researchers, although fewer than 1 percent of the genome undergoes a process called imprinting, in which an allele is transcribed into RNA and translated into a protein only if it comes from a specific parent. For instance, the IGF2 gene, which codes for the hormone insulinlike growth factor 2 in fetal liver cells, is only activated if it comes from the father. A version of monoallelic expression takes place in all female cells, where one of the two X chromosomes is randomly inactivated to eliminate redundancy. Genes that code for olfactory receptors, immunoglobulins (which produce antigens that trigger immune responses) and T cell receptors (that recognize antigens), also occur in populations of cells that express only one of their alleles, which actually results in a greater repertoire of antigens and receptors.

With the new work, the quantity of genes known to be vulnerable to this has ballooned to between 5 and 10 percent of the entire genome.

Chess's team took advantage of DNA microarray technology to survey the activity of certain gene variants in the genome of human B lymphocytes (white blood cells that, like T cells, help fight infection). By cataloguing point mutations in the genetic code, they could decipher when two different alleles were being transcribed from DNA into RNA (the template that provides the recipes to build specific proteins). They focused on a sample of just under 4,000 genes, nearly 400 of which appeared to undergo monoallelic expression.

Of those 400, several had previously been linked with human disorders, such as APP, the gene for amyloid beta precursor protein, which in excess quantities is believed to up the risk of Alzheimer's disease. Although no genes seemed immune to this process, researchers detected an abundance of cell receptor–coding genes in the mix. "The overabundance of receptors and other surface proteins suggests a role for monoallelic expression in each given cell's interactions with other nearby cells," the authors write in the Science paper.

Rolf Ohlsson, group leader of the mammalian epigenetics lab at Sweden's Uppsala University, wrote in an accompanying editorial that the findings may cause a shift in perspective on how scientists view illnesses believed to have a genetic component. "Anyone unfortunate enough to possess the 'wrong' set of monoallelically expressed genes might be susceptible to the earlier onset of a complex disease, such as Alzheimer's," his commentary read. "Considering the interplay among genotype, epigenotype and gene inactivation [these findings] will become more important in understanding developmental mechanisms and the penetrance of diseases in an individual as well as responses to medical treatments."

Next up: Chess says his lab will try to find triggers for monoallelic expression and probe whether genes can produce protein from one or both alleles at different times throughout a person's life span.

Our Evolving Present

Human changes to the environment are accelerating evolution in many ecosystems


The cane toads go bump in the night. I hear them banging as they misjudge where my hotel door ends and the forest begins. The force of a large toad knocking wood is substantial. But the force with which the toads, which are native to Central America, have hit Australia is even greater. Brought to Queensland in 1935 to combat beetles infesting sugarcane fields, the toads have spread out from their point of entry like the shock waves of a bomb, warty legs and oversize tongues jettisoned into every conceivable ecological crack.

Recent research by Ben Phillips and his collaborators at the University of Sydney has shown that the toads are evolving as they spread, perfecting their ability to adapt to the Australian landscape. The toads at the front edge of the invasion now have smaller bodies, reduced toxicity and relatively longer legs, apparently because individuals with those traits were having greater success. The native fauna has evolved in response: the mouths of some snake species are getting smaller, for instance, because so many of the snakes with big mouths were eating the poisonous cane toads and dying off.

Such examples are changing scientists’ views of the speed of evolution. The process was long considered to be slow, even lumbering. Increasingly, though, researchers are observing evolution in action. You may be familiar with the examples of the evolution of drug-resistant bacteria or agricultural pests. Microbes and pests may change the fastest, but they are not unique.

We see rapid evolution most often where some force (often us) has given it a jump start by suddenly and dramatically altering an organism’s environment. Rats have developed smaller bodies when introduced to islands. Trophy fish have also adopted smaller body sizes in response to fishers’ preference for big fish (which, if killed, do not breed). Mayflies in streams where trout were released now forage at night to avoid the fast-swimming predators. Many hundreds of herbivorous species have switched to novel, sometimes toxic, food sources introduced by humans and have come to specialize in consuming those new resources. Various native species have evolved in response to newly arrived competitors. Cedar trees have begun making toxins to protect themselves from being eaten by deer now roaming in their formerly benign habitats. Mussels in New England have evolved the ability to detect invasive green crabs and produce thicker shells where the crabs are present.

Most of these changes appear to have resulted from natural selection: organisms that by chance had some genetic trait that helped them thrive in the face of a new stress were favored, and subsequently they reproduced successfully and spread the helpful trait to future generations. But some evolutionary changes we see may simply be the result of genetic drift (random genetic changes that accrue over time).

The more we look, the more we can observe evolutionary changes that are fast enough to be seen during the course of a single study. A Ph.D. student might, in the five or so years of a dissertation project, realistically see the development of new species, whether in real time or using genetic tools to reconstruct evolutionary history. As house mice and rats have spread with us around the world, they have speciated into forms best adapted to the different regions where they live. In the northeastern U.S., a species of fly has evolved to feed on a species of honeysuckle introduced to North America less than 250 years ago. Although the new fly is a hybrid between two existing species, it can mate with neither one and maintains viable populations of its own.

People tend to imagine evolution as acting only on long-extinct creatures such as the dinosaurs, but the flensing knives of natural selection and the random pushes and pulls of genetic drift are still at work today. We see a red oak tree in our backyard or a cane toad at our hotel-room door, but the names fool us. These species are not the same this year and next. Although the evolution we observe in real time will not suddenly give us dinosaurs, it is still a process to be reckoned with. Give natural selection a few individuals of any species, and it will work the same way in a waste pool as it does in Yellowstone National Park. Nature abhors a vacuum, but nearly anything else will do.

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