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I may say with truth that whenever I consider in my thoughts the beautiful order, how one thing issues out of and is derived from another, then it is as though I had read a divine text, written into the world itself, not with letters but rather with essential objects, saying: Man, stretch thy reason hither, so that thou mayest comprehend these things. | ||||
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City of Gilgamesh Found in Iraq 04/30/2003 Now that Iraq has been liberated, we hope many discoveries will follow in this region of the cradle of civilization.ET Could Not Evolve 04/30/2003 If Steven Spielbergs extraterrestrial from the movie ET really had six-letter genetic code, it could not have evolved, says the BBC News reporting on a study by scientists from New Zealand and Sweden who tried evolution by supercomputer. The four-letter base, like our own DNA, is the optimum magic number. The conclusion is based on a scenario of an RNA World evolving into DNA. Four-base RNA showed both the best ability to copy without errors and to evolve into DNA, the researchers claim. Interesting, but the RNA World story is irrelevant because it would not work. RNA neither forms spontaneously in nature, nor is durable enough to survive in a primordial soup, where it would rapidly hydrolyze and degrade. Moreover, it cannot copy itself. We have the optimum base for our genetic code because it was designed to do what it does, and it does it very well. See also another recent evidence of good coding design in our genetic code: the bases used in DNA are even parity.Laziness, Not Diet, Is Bigger Factor in Obesity 04/30/2003 A study of youth obesity reported in Science News 163:17 indicates that people get fat primarily from exercising less, not eating more. During the past two decades, teen calorie consumption rose only 1 percent, but prevalence of overweight teens has tripled to 15 percent. This parallels a 13 percent drop in physical activity over the same period. Lisa Sunderland of University of North Carolina, who conducted the study, said that by 2000, only 29% reported they exercise regularly. Our bodies were made for vigorous physical activity, but todays ease of sitting in front of TV screens or computer monitors for long hours requires will power to make time for exercise. Diet is important, too, but no pill or food can compensate for lethargy. The Proverbs of Solomon satirize the sluggard, and honor the diligent. Exercise does a body good and a mind, too. Along with physical fitness comes improved attitude, happier outlook on life, endurance, reserves of energy, and ability to accomplish more. Exercise rewards a person with terrific-feeling endorphins and a sense of satisfaction. Your body is a marvel of design that feels and looks great when working at optimum performance. Use it or lose it. Start at your own level and make some gains. Recommendation: Instead of using a boring treadmill at a gym, go take a hike surrounded by the wonders of creation. Theres no better time than right now. Go fill those lungs with the delicious fresh air of spring. Then come in for a good cup of tea for your immune system and some creatine with whey protein for your fatigued muscles.Sea Bird Sets World Record 04/30/2003 A Manx shearwater captured on an island off the coast of Wales had a band on its foot put there in 1957. Since the bird was already 4-6 years old when banded, that makes it the oldest wild bird ever captured: about 52 years old. Experts at the British Trust for Ornithology calculated how many miles it must have flown in its lifetime. The result? About five million miles, enough to circumnavigate the globe 200 times. The story is reported in New Scientist. For a description of the Manx shearwater, see the Royal Society for the Protection of Birds website. Man-made aircraft could only survive that much airtime with constant maintenance. Birds have all that upkeep technology built in. The Manx shearwater is also a champion navigator. Birds transported to New England and released have found their way unerringly to their exact nesting sites on tiny islands off the coast of Wales. One wonders what stories this Olympic bird could tell from its long and busy life.How the Cell Avoids Typos 04/29/2003 Some of the most intriguing molecules involved in protein manufacture are the set of 20 molecular machines that fasten amino acids onto transfer RNAs. They are called aminoacyl-tRNA synthetases (aaRS) and it is their job to be certain that the correct amino acid is mated to the correct transfer RNA (tRNA). They are like language interpreters, in that they understand both the DNA language of nucleotides and the protein language of amino acids. Just like an interpreter must carefully match an English word to its Chinese equivalent, the aaRS interpreters are key players for ensuring the resulting protein chain is spelled correctly. Human interpreter errors can be funny (a Chinese interpreter once translated the American idiom out of sight, out of mind as invisible idiot). But in the cell, mistakes can be disastrous, leading to cell death. One difficulty of their job is that some amino acids are very similar to others. Linus Pauling once predicted an error rate of 1 out of 5 (80% accuracy) between isoleucine and valine, since they are differ only in weak van der Waals forces; but experimental evidence shows that the aaRS interpreter scores correctly 2999 times out of 3000 (99.67% accuracy). How do these sightless molecular machines discriminate between nearly identical twins, and almost always pick the right one? An international team of biochemists publishing in the April 25 issue of Molecular Cell has followed the activity of a couple of these interpreters in unprecedented detail. Before attaching the amino acid, the aaRS machine validates it with a double-sieve mechanism, which is like forcing the entrant to open two locks with two independent keys, or making him supply two passwords to two different security guards. It performs both pre- and post-transfer editing. In other words, it validates the incoming amino acid before attachment, and double-checks it after attachment. To begin with, the attachment will not proceed unless the tRNA is charged and the amino acid is activated. The active site for the leucine aaRS machine includes a discrimination pocket for the side chain of the amino acid leucine. Simultaneously, it authenticates the adenine of the RNA. If the parts dont match, or a hacker tries to sneak past, the aaRS machine holds the amino acid in position to be hit by the water-balloon firing squad; an incoming water molecule hydrolyzes both substrates, so that no further harm will come from the mismatched tRNA. The properly-edited tRNA then moves to another machine complex, the ribosome, that joins the amino acids together on an assembly line; here, additional proofreading mechanisms check for accuracy. Then the assembled protein chain moves onto the chaperone for correct folding, then to the intercellular railroad for shipping, etc. The team found a critical aspartic acid in the active site of the leucine aaRS interpreter that is universally conserved in very different organisms. Mutating it to something else, like alanine, destroys the editing function. So far, scientists have learned about four proteins that can deacylate charged tRNAs, and they have completely different structural frameworks. Small changes in these machines also cause a dramatic effect upon editing. The accuracy of the aaRS system is just one of many levels of quality control ensuring cell survival. The authors state, Our results demonstrate the economy by which a single active site accommodates two distinct substrates in a proofreading process critical to the fidelity of protein synthesis. This system hardly needs comment. It speaks so loudly about intelligent design that only willful unbelief could claim such a system evolved by random, undirected natural forces. Language translation, quality control, triple-checking failure analysis, pre- and post-translation authentication, error disposition, precision parts, irreducible complexity ... what more needs to be said?How Does a Stem Decide to Become a Leaf or Flower? 04/29/2003 Its the simple questions that sometimes yield the most interesting answers. What junior high kid in a science class hasnt experimented with bean seedlings, watching them germinate and grow toward the light? Many people have seen time-lapse movie clips of germinating plants emerging out of their seeds. The initial shoot splits into branching stems, and leaves start appearing. At a certain stage in the growth cycle, flowers appear, followed by fruits. Have you ever wondered how a plain-looking stem, called an apical meristem, decides to grow a leaf or a flower? Scientists are continuing to learn more of the details at the genetic level, and the emerging picture is quite amazing. In the April 29 issue of Current Biology, Peter Doerner has provided an overview entitled, Plant Meristems: A Merry-Go-Round of Signals Review. He introduces the subject: Growth and organ formation in plants occur post-embryonically, mediated by meristems located on the tips of growth axes in shoots and roots. Meristems are unique structures made up of pluripotent stem cells, a transitory population of indeterminate cells and determinate organ primordia formed at the periphery. Secondary growth, which increases the girth of stems, is mediated by cambial cells, which continue to add vascular cells to the circumference of the central, vascular cylinder of the plant.While shoot meristems produce geometric patterns of leaves and flowers, the root meristems produce stochastic or indeterminate branching arrangements. The meristem center has three layers of slowly-dividing cells. Doerner says that Low rates of cell division reduce the likelihood of mutations affecting the large sectors of the aerial plant body produced by individual stem cells. On the flanks, however, are cells that divide more rapidly, and when an organ needs to start forming, proliferation increases markedly. Something has to signal the meristem to begin producing an organ like a leaf or flower. This has certain requirements (emphasis added): Meristems mediate plant growth and hence are dynamic structures in which cells transit through zones with distinct developmental potential. The coordination of growth with development in such dynamic structure requires extensive short and long distance intercellular signalling. A conceptual framework for meristem function must include at least the following elements. First, meristems must have a capacity to specify an indeterminate cellular ground state. Second, a subset of these indeterminate cells must acquire stem cell identity, ultimately replenishing cells lost to organs and maintaining genetic integrity.. Cells in this stem cell niche must self-regulate their activity to not disappear or overproliferate. Third, indeterminate cells must have the ability to acquire determinate fates associated with organogenesis.An analogy from recent military news might help explain what these cells accomplish. Imagine an army sent into a battlefield, where each soldier is pluripotent or able to do any job required. They are sent out, not yet knowing what specific job they are going to have to do. This is the indeterminate state. At some point, signals come into their walkie-talkies giving orders: Bob, you are to be a tank missile launcher, or Jessica, take over medic responsibility in the infirmary. These soldiers then acquire determinate fates and do their jobs with skill and precision, including the ability to act autonomously and coordinate with other soldiers in their vicinity. In the plant, there are feedback loops maintaining dynamic equilibrium (homeostasis) that is very effective. Doerner comments, Stem cell homeostasis is maintained astonishingly well within tight bounds, as the longevity of the shoot apical meristem of trees demonstrates. In an army, all this cooperation would not work without the generals giving the proper signals from headquarters. A plant, however, does not have a centralized headquarters, like a brain. How does it do it? Each cell has a copy of the DNA master plan, but One of the major unresolved questions of meristem function is the nature of the mechanisms by which signalling occurs to establish specific patterns of gene expression. Biologists have long known about chemicals called auxins and gibberelins that enhance or suppress growth at the meristem, but recent work has led to a startling observation. Small bits of RNA, called micro-RNAS (miRNA), a recently discovered, novel class of non-coding regulatory RNAs found in animals and plants may be responsible for patterning. Another class of RNAs called short interfering RNAs (siRNA), distinct from miRNAs, are involved in epigenetic regulation mediated by DNA and histone regulation. Doerner explains, Therefore it is likely that several small RNA-mediated processes participate in precipitating, enforcing or maintaining patterning decisions. But what controls the RNAs? Do they mastermind the expression, or just enforce developmental decisions? No single master regulator has been identified sufficient to specify shoot or root meristems originating from any single cell, Doerner observes, and from the emerging paradigm for meristem function it is unlikely that such a gene exists. So while we know that meristem homeostasis thrives on antagonism: negative feedback loops and juxtaposition of cells with divergent developmental fates, and while we think small RNA-dependent processes are good candidate mechanisms to effect changes in expression levels or patterns in the short term or for longer periods by epigenetic mechanisms, Doerner leaves the central question unresolved: No clear candidates for morphogens have yet emerged, meaning that while the soldiers are well-trained and exquisitely coordinated, we do not see a clear central command that makes the decision and sends the orders, Grow a flower right here. One of the first amazing stories we reported back in July 2001 was that plants have their own internet, and plant cells talk to themselves in email. This updated report shows that the interplant internet is even more mysterious and wonderful than we imagined. Without a brain, without a general, without a headquarters, a beehive of activity functions with goals and coordination and timing. Flowers appear on schedule. Leaves unfurl with mathematical precision. Roots dive into the dark soil, fruits ripen, seeds disperse, water and minerals flow through the vessels, and dozens of other functions work not haphazardly but with astonishing levels of dynamic equilibrium and effectiveness. Two wonders are evident in this paper: (1) Epigenetic mechanisms are at work. This means that DNA is not a master control; something is controlling the DNA itself. (2) Elaborate signalling takes place. The micro-RNAs are like email messages delivering the orders to local indeterminate cells, causing them to became flowers, leaves and fruit.PBS Offers Intelligent Design Documentary 04/28/2003 According to Illustra Media, the Public Broadcasting System uploaded the film Unlocking the Mystery of Life to its satellite this past Sunday. For the next three years, it will be available for member stations to download and broadcast. In addition, PBS is offering the film on their Shop PBS website under Science/Biology videos (page 4). The film, released a little over a year ago, has been called a definitive presentation of the Intelligent Design movement. With interviews and evidences from eight PhD scientists, it presents strictly scientific (not religious) arguments that challenge Darwinian evolution, and show instead that intelligent design is a superior explanation for the complexity of life, particularly of DNA and molecular machines. The film has been well received not only across America but in Russia and other countries. Many public school teachers are using the material in science classrooms without fear of controversies over creationism or religion in the science classroom, because the material is scientific, not religious, in all its arguments and evidences, and presents reputable scientists who are well qualified in their fields: Dean Kenyon, Michael Behe, Jonathan Wells, Steven Meyer, William Dembski, Scott Minnich, Jed Macosko, and Paul Nelson, with a couple of brief appearances by Phillip E. Johnson, the founder of the Intelligent Design movement. Check with your local PBS Station to find out when they plan to air it. If it is not on their schedule, call or write and encourage them to show the film. Why should television partly supported by public tax funds present only a one-sided view on this subject, so foundational to all people believe and think? We applaud PBSs move, but it is only partial penance for the Evolution series and decades of biased reporting on evolution.How a Materialist Writes A Users Guide to Life 04/25/2003 Is the soul a collection of neurons on the brain? A materialist must think so. Some would put more emphasis on nurture, beyond just nature (i.e., culture and environment, other than just the wiring). Either way, how does a materialist explain our sense of self and our deepest longings, and how does one explain evil? In the Apr. 25 issue of Science, Nathan J. Emery reviews a new book by two who enthusiastically embrace the reductionist manifesto, Steven R. Quartz and Terrence J. Sejnowski, entitled, Liars, Lovers, and Heroes: What the New Brain Science Reveals About How We Become Who We Are. Emery sets the stage (emphasis added): Can an understanding of brain science ever uncover the answers to the big questions of life: Who are we? How did we become who we are? And what does it mean to have an individual self different from other selves? Many scientists think so. Francis Crick, for example, has suggested that You, your joys and your sorrows, your memories and ambitions, your sense of personal identity and free will, are in fact no more than the behavior of a vast assembly of nerve cells and their associated molecules. He even went as far as to state that the seat of the soul was located in the anterior cingulate cortex. And there is a constant stream of new research that attempts to answer these fundamental questions using sophisticated neuroimaging techniques. A recent trawl through the cognitive neuroscience literature reveals studies of the neural bases of cooperation, self-recognition, gender stereotyping, romantic love, humor appreciation, facial attractiveness and aesthetics, and the attribution of others mental states. But at a fundamental level, one wonders whether the attempts of such research to demystify the mysteries of life are futile. If we found the location of self in the brain, would that discovery tell us any more than we already know from our individual experiences?The book takes a reductionist approach similar to that of Crick, but they argue that these biological systems can only create a psychologically whole person through interactions with the cultural environmentinteractions that affect the structure and function of neural circuits. They call this cultural biology, according to Emery, who describes the main idea behind their highly cognitive sense of the self: The crux of Quartz and Sejnowskis thesis is the suggestion that the neural basis of our individual nature is located within the prefrontal cortex, which they call the users guide to life (emphasis added). But he wonders why this is news. Every scientist he knows already accepts the assumption of an interplay between heredity and environment, not the strictly reductionist idea that brain chemistry alone determines our sense of self. The value of the book, Emery believes, is in providing a wake-up call to neuroscientists: Sometimes students of the brain forget that brains are party to evolutionary processes, do not work in isolation, are not fixed from birth, and can change depending on the environment. A failure to take this information into account would be detrimental to all subsequent studies of mind and brain, he says (emphasis added). Having thus justified the book, Emery is left with a strange aftertaste (emphasis added): At the end of the book, I was left wondering what the authors had actually said about how we become who we are and about how we can use the knowledge of personality development that we already have. I expected to find such uses addressed in the afterword on the terrorist attacks of 11 September, but there I found nothing except a politically charged statement. As I write this, another suicide bomber has killed 20 in Israel, and the United States and the United Kingdom are preparing to go to war with Iraq. I ask myself what could be done about such problems if we had the kind of information this book purports to present. Terrorists do not tend to have a defined psychopathology, and therefore they are unlikely to have a biological deficit in their psychological makeup. Does this mean that many of the flaws in human (and individual) nature are due to culture alone?Emery gives the authors some credit for at least raising consciousness on these questions: Despite its many shortcomings, Liars, Lovers, and Heroes does provide a reasonably good place to start asking these sorts of questions empirically. Did you catch the lesson of this reductionist dialogue? If so, you found the Achilles heel of materialism. It is the crux of the debate about who we are, and how we became who we are: it is the inescapable reality of conscience. These materialists have an innate sense of good and evil, that evil is bad and should be stopped, but they do not know what to do with it. Their own materialism ties their brains in knots. On one side, everything evolved, so the brain evolved and evil evolved. No moral standard exists; everything can be reduced to nature and nurture. Whatever is, is right. On the other side, both Emery and the authors cannot live with this philosophy. Evil happens, and it should be stopped!Titans Ice Reflects Young Surface 04/25/2003 A team of scientists found evidence of water ice on Titan, the haze-shrouded largest moon of Saturn. This represents a problem. The international team of planetary scientists and astronomers, publishing in the Apr. 25 issue of Science explains that we shouldnt be able to see the icy bedrock of Titan, because dark compounds ought to have buried it long ago (emphasis added): Methane, the second most abundant atmospheric constituent (0.05 bar) detected after N2 (1.4 bar), is continually and irreversibly destroyed by solar ultraviolet photolysis, a process rapid enough to require a recent supply of methane. Two end-member scenarios are possible. Ongoing geologic activity supplies atmospheric methane (and leads to an atmosphere that varies in size with supply), or ocean reservoirs of methane exist as a result of past geologic activity. The products of methane photolysis, a variety of simple and complex organic compounds, precipitate to Titans surface, leaving a history of Titans atmospheric composition. If Titans atmosphere has existed in its present form since its formation, ~800 m of organic liquids and solids blanket Titans surface.Thats roughly 2,600 feet thick of methane products. Yet presumably Titans solid surface is composed largely of water ice, as on Ganymede or Enceladus. How can the ice show through such a thick blanket? The authors do not offer a suggestion. Most of their report focuses on how they detected the water ice through narrow windows in the smog at 8 wavelengths. We derived a spectrum of Titans surface within these windows and detected features characteristic of water ice, they state without theorizing. Therefore, despite the hundreds of meters of organic liquids and solids hypothesized to exist on Titans surface, its icy bedrock lies extensively exposed (emphasis added). More detailed and extensive data are expected to be received when the Cassini Spacecraft makes its first flyby of Titan on July 1, 2004, and especially when its detachable Huygens Probe parachutes down to Titan for the first-ever in situ measurements and photographs of the atmosphere and surface. The BBC News and Space.Com both report on this story, quoting some who suggest that maybe somehow the blanket of material moves around or goes through cycles to expose the icy surface. Space.Com also has a weather diagram explaining the differences between Titan and Earth weather. Unlike on earth, where the sun is the driving force, energy released during condensation drives much of the weather on Titan. But that condensation energy would need to be compensated by an energy source to drive evaporation to keep the cycle going. This is one of many phenomena in the solar system that argue against the commonly-accepted age of 4.6 billion years. (1) In the first place, all the methane should have eroded by now into products blanketing the surface. (2) In the second place, if organic compounds have been raining down to the surface for that long, there should be a blanket over half a mile thick covering any water-ice surface, yet today, water ice is detectable.How Hummingbird Beaks Coevolve With Flower Shape 04/25/2003 Island ecosystems, isolated and self-contained, have been studied since Darwins day as laboratories of evolution. In an Enhanced Perspective piece in the April 25 issue of Science, two evolutionists highlight the relationship between the hummingbirds and their nectar sources on the islands of the Lesser Antilles. The curvature of the beak correlates to the shape of the flower. Female beaks in some species are longer and more curved than those of males, but males have larger and heavier bodies. The sexes tend to feed on flowers that match their characteristics. While the sexual dimorphism seems a response to foraging, it casts doubt on assumptions that sexual dimorphism is a measure of sexual selection. The authors consider this a fine-tuned coevolutionary dance (where evolution of the flower affects the evolution of the bird, and vice versa), yet they admit puzzles remain: On the other side of the equation, how do differences in animal feeding behavior and efficiencies affect plant fitness? Gene flow is clearly available to plants with traplining pollinators [i.e., birds in which the sexes feed on different flowers], but how do plants with territorial pollinators accomplish genetic outcrossing? Also, does the consumption of insects by hummingbirds directly influence hummingbird morphology and indirectly influence flower morphology? Once again, islands may provide the ideal setting for answering these questions. The Darwinists are never done with their stories. Its always going to take more studies (and more funding, and more Caribbean cruises). Here you have a study that undercuts one of Darwins pet theories, sexual selection, but demonstrates no clear cause-effect relationship between variation and fitness, or between morphology and the species responsible for the variation: the flower, insects, or the other sex of the hummingbird. There are enough loopholes in the tale to drive a tank through. Even if the birds and flowers are coevolving, the birds are still birds and the flowers are still flowers. So what does this story have to do with Darwinian evolution, the origin of hummingbirds and flowers from bacteria? Nothing. Even creationists unabashedly affirm this amount of variation, and are the first to exhibit, in their lectures, colorful montages of dogs, horses and people in all their varied glory. One cannot extrapolate recklessly a function that is not known to be linear. Some functions rise gradually and then fall sharply to zero. All observable, repeatable studies show that variation has limits. If it stays within limits, it is variation, but not evolution in the sense most people understand the word. Writing a paper as if small-scale microevolution has anything to do with Darwins theory of common ancestry is equivocal and misleading.Cave Date Puts Hominids Too Early 04/25/2003 Results are in from the dating game, says Science Magazine 04/25/03, but the contestants are not happy. Darryl Granger used a new dating method to estimate the age of remains in Sterkfontein Cave, South Africa, and concluded the hominid skeleton there is 4 million years old, nearly a million years older than the oldest previous estimate. Others dont buy it. That puts australopithecines in south Africa far earlier than expected, and makes Little Foot (one of the skeletons) the contemporary of Lucys ancestor. Yet the skeleton does not resemble that ancestor in crucial aspects, complains one investigator. To add confusion, dates from recent discoveries in nearby Jahovec Cave may represent two types of australopithecines, suggesting a diversity of 4-million-year-old hominids. Critics feel use of the cosmic radionuclide dating method is on shaky ground because of the complexities of the cave environment. A news report on the story can be found at Purdue News. So the hominid wars carry on. As usual, shaky method + shaky assumptions = shaky story. If contemporaneous australopithecines showed significant diversity, on what basis can scientists arrange them into an evolutionary relationship? See also Tim Whites damaging assessment of assumptions used in interpreting hominid bones in our March 28 headline.Are Metal-Poor Stars Closer to the First Generation? 04/24/2003 Astronomers have a strange convention of calling anything heavier than hydrogen and helium metals even it is oxygen, iron or carbon. Most stars have a good portion of the periodic table of elements represented in their spectra, but last year a star with only 1/200,000 the suns metallicity was discovered. This excited astronomers, because they believe the big bang created only H and He, so every other element would have had to be formed within stellar interiors by fusion. (Most elements heavier than iron would require a supernova explosion.)  That means the first generation of stars would have to be composed of only hydrogen and maybe some helium, but no pure stars without metals have ever been detected. The lower the metal content, however, the closer to the beginning, they assume, because it would have formed out of a cloud not yet enriched in metals. The picture is not quite so straightforward. In the April 24 issue of Nature, three conflicting papers try to explain the puzzling spectrum of HE0107-5240. Though its overall metallicity is low, it has an anomalously high C/Fe ratio, 10,000 times that in our sun, and a nitrogen abundance enhanced over the suns ratio by a factor of 200. In the News and Views summary of these papers, Timothy C. Beers of Michigan State sorts through the frustrating variety of possibilities the data permit. Astronomers cant tell if this star formed out of a metal-poor cloud, if it started out metal-rich but became depleted, or if it was salted with its metals by nearby supernovas. Though optimistic, Beers believes numerous additional stars with extremely low Fe abundances will need to be discovered to fully tell the tale of early star formation and the creation of the first metals in the Universe. I.e., those stars have not been discovered yet. We think people should know that the simplistic story of nucleosynthesis, leading to Carl Sagans oft-quoted line we are all made of starstuff is not so simple when you look at the actual data. If the big bang started with only hydrogen, why do virtually all stars already have heavy elements? Notice that even HE0107-5240 contains nine elements: H, C, N, Na, Mg, Ca, Ti, Fe, and Ni, which Beers admits present a dizzying array of possible explanations for their origin. Its not that scientists are unable to concoct a story around the data, its the data require a story to fit a belief.Navajo Sandstone Theory Proposed 04/24/2003 The Navajo Sandstone of Utah-Arizona is one of the most remarkable landforms of the American southwest. It reaches over 2000 feet in thickness at Zion National Park. Some of its outcroppings are bizarrely beautiful, as in the striking crossbedded strata at Coyote Buttes. Its canyons are meccas for hikers (as in Paria Canyon) and photographers, such as the dramatic slot canyons like Antelope Canyon. How did this varied and colorful landscape, which extends from mid-Arizona up into Colorado, Wyoming and Idaho, form? In the current (March 2003) issue of the Journal of Geology, David Loope and Clinton Rowe of the University of Nebraska investigate the Navajo Sandstone, one of the largest sand seas known in Earth history, which they describe as an ecological/depositional system without an obvious modern analog. After identifying various features within the Coyote Buttes, including fossils such as burrows, dinosaur tracks and insect nests, they describe the region as a large area of dry sand dunes interrupted by pluvial (wet) periods of heavy monsoons. Although the study area including Buckskin Gulch could be interpreted as originating from a single pluvial episode, they argue that two long-lived, monsoon-dominated wet periods were required to explain some overlapping bioturbated features described in the paper. Geology is a fascinating science. Researchers have to get out into some wild country, some of it remote and harsh, and describe phenomena ranging from microscopic grains to vast regions covering several states or sometimes continents. Needless to say, geology theorizing is also an art. A geologist can often find similarities to current processes, but many times there are formations without an obvious modern analog, as here. What then? The geologist proposes a theory that tries to explain as many details as possible, but it can never be thoroughly tested, because the true story is hidden in the unobservable past. It can only achieve a certain measure of plausibility.Atheist Reviews Atheist Book 04/23/2003 In the Apr. 24 issue of Nature, Jerry Coyne, an evolutionist at the University of Chicago, reviews a new book by the foremost advocate of Darwinian evolution today, Richard Dawkins. Strangely, the book has a religious title: The Devils Chaplain. (The title is taken from an atheistic evangelist, Robert Taylor, who stormed Cambridge in Darwins student days.) Dawkins takes Taylors chair in this polemic against all religion, preaching atheistic science with a passion that Coyne finds almost startling. Coyne counts six of the 32 essays in the book dealing directly or indirectly with religion, a surprising statistic for a science writer whose chair at Oxford University is dedicated to the public understanding of science. Attacking organized religion as well as pseudoscience, Coyne remarks, Clearly, Dawkins sees his brief as not only popularizing science, but demolishing its competitors. Another surprise is that Dawkins other bugbear in this book is another atheistic evolutionist, his erstwhile nemesis Stephen Jay Gould. Most evolutionists are aware of their heated disagreement regarding speciation, Gould promoting punctuated equilibria and Dawkins fiercely defending traditional Darwinian gradualism. But Dawkins also had little patience with Goulds accommodating spirit toward religion (as long as it keeps its hands out of science). Dawkins feels no rapprochement is possible; religion, in his opinion, is the vehicle of evil, xenophobia, and delusion. Coyne notes that Dawkins is a fierce advocate of scientism, the philosophy that genuine truths — as opposed to spiritual or personal truths that are not universally held — can be found only through the scientific method. He groans at Dawkins endorsement of meme theory, which he calls the collections only low point, given my view that mimetics is an extended tautology that has yielded no real understanding of human culture. Notwithstanding these critiques, Coyne makes it clear he sides with Dawkins in the attacks on religion. He says, Dawkins aficionados outside Britain have had little exposure to his withering assaults on religion, pseudoscience and accommodationism. Its a rare treat to see him sail into battle, prose and logic perfectly attuned to the destructive business at hand. In his concluding sentence, Coyne states, Dawkins makes a strong case that most religions are insidious and dangerous illusions. Its time for those who agree to stand up beside him. In the same issue of Nature, David Hull reviews Goulds last book (published posthumously). He says, Gould spends a lot of time debunking the myth of objectivity as a psychological characteristic of scientists. Self-delusion is tragic, but it is doubly so when one thinks its the other guy who is deluded. If Coyne has accurately summarized Dawkins views in this book, the two of them espouse self-defeating claims. Coyne admits plainly that Dawkins is a fierce advocate of scientism (similar to logical positivism), an outdated 19th-century philosophy that shoots itself in the foot with the self-referential fallacy. I.e., scientism was not discovered by the scientific method, so it is not scientific. If we are only to accept what has been found through the scientific method, then we must reject scientism with the same ferocity we reject other further impassible routes to knowledge (such as homoeopathy, crystal worship and postmodernism). As one of our readers pointed out, their position is also self-defeating in that it judges things as good or bad, when evolution provides no moral standard. Hey, if religion evolved, then it must be good. Why knock it?Quick Picks 04/23/2003: National Geographic News posted some interesting nature stories that illustrate the variety of organisms inhabiting our planet and their amazing capabilities:
Garbage (and Almost Anything Else) In, Oil Out 04/22/2003 Making oil and gas from hydrocarbon-based waste is a trick that Earth mastered long ago. Most crude oil comes from one-celled plants and animals that die, settle to ocean floors, decompose, and are mashed by sliding tectonic plates, a process geologists call subduction. Under pressure and heat, the dead creatures long chains of hydrogen, oxygen, and carbon-bearing molecules, known as polymers, decompose into short-chain petroleum hydrocarbons. However, Earth takes its own sweet time doing this--generally thousands or millions of years--because subterranean heat and pressure changes are chaotic. Thermal depolymerization machines turbocharge the process by precisely raising heat and pressure to levels that break the feedstocks long molecular bonds.Unlike previous attempts at getting oil from organic matter, TDP is energy-efficient, only using about 15BTU for every 100BTU produced. Investors and the government are supporting TDP development and expect the first operational center to be running in 2005. By then, Lemley concludes, it should be clear whether the technology is as miraculous as its backers claim. On a related subject, National Geographic has a news item about the use of vegetable oil to replace fossil fuels. This sounds like a superb example of applied science with benefits for all. Anything that reduces our dependence on foreign oil and can make useful products out of waste is good stewardship of the environment. Can it really be that this process is all good news and no bad news? Well have to wait and see.Age of Chauvet Cave Art Disputed 04/22/2003 A debate is rising over the claim Frances cave art in Chauvet is 30,000 years old, says New Scientist. Some critics think the radiocarbon date is unreliable since it was done at one lab. They also imagine it hard to believe that the best cave art was 15,000 years earlier than thought; the earliest art should have been more primitive and improved as early man evolved. Chauvet cave was discovered in 1994. When the paintings were dated by the Carbon-14 method, the results shocked everyone. Let this be a lesson in the unreliability of dating methods and in the implausibility of evolutionary assumptions about the rise of man. See also our July 2001 and Oct 2001 about Chauvet Cave. What about the Italian cave art National Geographic reported November 2001 that was claimed to be 35,000 years old and just as good?Stem Cell Update 04/22/2003: New Scientist reports on a promising source of stem cells, better than adult stem cells, that also avoids the destruction of embryos, which pro-life groups oppose. The source? Baby teeth. Dont tie your kids tooth to the doorknob just yet. EurekAlert reports that human stem cells might also be produced by parthenogenesis, another method that would avoid the ethical concerns that have led to restrictions or bans on embryonic stem cell research in many countries. The stem cells from this method appear to be indistinguishable from embryonic stem cells. On April 24, EurekAlert reported that scientists at University of Minnesota, working with lab mice, succeeded in getting stem cells from adult bone marrow to differentiate into all brain cell types. Next headline on: Politics and Ethics.
How Long Can Fossil DNA Survive? 04/21/2003 Why do these scientists believe these samples are 400,000 years old? One word: evolution. They dated their samples on the presumption that animals have slowly evolved over millions of years from flatworms to mammoths, and with that assumption guiding everything, made their claim. They used index fossils to date these samples, a method dependent on evolutionary assumptions that is how they determined what a 30,000 year mark is, and so forth. But there are good reasons to believe DNA could not survive that long. The fact that the DNA of leafy plants and moderate-temperature animals like horses is locked in permafrost should make one think of alternatives. The samples do not show evolution; they show extinction, and stasis of some plants and animals that were fortunate to survive whatever drove their fellow critters under.Archaeology Update 04/21/2003: National Geographic News led today with two stories about ongoing efforts to validate two recent archaeological discoveries of Biblical interest: the James ossuary and the Joash inscription. The bottom line is that it is difficult to verify artifacts that come from dealers rather than being dug up in situ. Techniques involve paleography, or research into the writing habits and styles of the period, and analysis of the materials, including the amount of weathering and the freshness of the inscriptions. While authenticity seems likely, there are doubters, and more work remains to be done. One must also keep in mind the strong religious and political feelings on both sides, such as the desire by Jews to validate claims to the temple mount and the Arabs desire to contradict it. There are also opportunists seeking to take advantage of these desires, and to fake spectacular finds (this also is a danger in the Chinese fossil market). A rush to judgment or lack of care in analysis can sometimes backfire by giving an impression of lack of objectivity. Nothing has ruled out these two artifacts from being genuine, but keeping a cool head is hard to do in such a highly polarized emotional atmosphere. Let the experts do their analysis and let all sides be heard. As interesting as these artifacts are, their authenticity (or doubts about it) should not in any way diminish the serious study of the Scriptures.Peppered Mice? 04/18/2003 In a mammalian version of the famous peppered moth study by Kettlewell, some Arizona biologists have studied dark- and light-colored mice. Color variants of rock pocket mice, Chaetodipus intermedius, were collected from natural populations in Arizona and New Mexico. Most of the dark-haired mice live on dark lava, and most of the light-haired ones live on light-colored rock. These scientists wanted to go beyond the work of Kettlewell and determine the genetic basis for melanism (darkening of coloration) in these mice. They begin (emphasis added), A key problem in evolutionary biology is to connect genotype with phenotype for fitness-related traits. Finding the genes underlying adaptation has been difficult for a number of reasons. First, it requires that we identify traits that are ecologically important and that we have some understanding of how these traits affect fitness in different environments. Second, phenotypic variation of ecological relevance has often been studied in species for which we have little genetic information, making the genetic basis of the traits difficult to analyze. For example, one of the best known cases of adaptation involves color morphs of the peppered moth Biston betularia. Yet, after more than a half-century of study, the genes responsible for the color differences remain unknown. Finally, many fitness-related traits are quantitative and are unlikely to have a simple genetic basis. Because of these difficulties, the molecular basis for adaptation is known in only a handful of cases. Most involve either biochemical polymorphisms or response to human disturbance, such as heavy metal tolerance in plants, insecticide resistance, warfarin resistance in rats, or antibiotic resistance, and in many cases, the specific nucleotide changes have not been identified.These scientists looked into the genes of their mice for clues. In a gene known to be responsible for hair color, they did see some frequently occurring patterns in the gene Mc1r among the dark mice; four out of nine single-nucleotide polymorphisms were found only among the dark mice at one of the collection sites. This, they feel, lends a genetic basis to the the melanism occurring there. But to their surprise, the population collected in New Mexico did not have these patterns in this gene. They say that this indicates that a similar dark phenotype has evolved independently on these different lava flows and has done so through different genetic changes, although the gene(s) involved in the Armendaris population have not yet been identified. The distinct molecular basis for the same phenotype in two different populations provides strong evidence for convergent phenotypic evolution on a relatively short timescale; both lava flows are less than one million years old. So although their genetic linkage to phenotype was only a partial success, they feel this illustrates natural selection in the wild. Owls are presumed to be the primary agent of selection, since they are assumed to detect the contrasting color more easily. The data reported here, they conclude, present a rare example of the molecular changes underlying adaptation in a simple and natural ecological setting. The paper is entitled The genetic basis of adaptive melanism in pocket mice, by Michael W. Nachman, Hopi E. Hoekstra, and Susan L. D'Agostino of the Department of Evolutionary Biology, University of Arizona, Tucson, published in the April 18 online preprints of the Proceedings of the National Academy of Sciences. For a summary, see the May 15 article on SciNews. You wont get any fair analysis on the SciNews link, which is another example of the kind of fawning, gullible, gutless, mousy science reporting that cannot bring itself to ask any hard questions, but takes whatever a scientist says as if it were a Delphic oracle. So we will rise to stand in the gap. What does this story prove about evolution? Zilch.Cell Celebrated 04/17/2003 The April 17 issue of Nature features a collection of reviews on cellular dynamics: cell division, the cytoskeleton, microtubules as molecular machines, molecular motors, and more. In the overview article, Thomas D. Pollard of Yale sees this all as the triumph of the reductionist agenda: i.e., that all this complexity can be explained from simple evolutionary precursors. No long comments this time, since this is more of the same intellectual schizophrenia we have discussed so many times before. Interestingly, the other authors, who describe the fine details of molecular machines, have very little to say about evolution, but Pollard waxes eloquent about it. His remarks are characterized by sweeping generalities of bluff so characteristic of evolutionary prose, authoritative pronouncements that the peasants are supposed to just accept with awe because he, a scientist, says so. Examples: (1) Genes for actin and tubulin arose in prokaryotes. How? He doesnt say. They just arose (the miracle of emergence). Does he have any idea how mathematically improbable that is, that a mindless one-celled organism could invent the complex three-dimensional parts of a railroad system? Shh! Its not polite to interrupt a scientist during his oracle. (2) In a fascinating role reversal early in eukaryotic evolution, actin filaments took over cytokinesis and microtubules assumed the partitioning of the genome. Awesome! Those little mindless molecules sure are smart! (3) Moreover, nematodes evolved completely different cytoskeletal polymers for their amoeboid sperm. Wow! Worms are even smarter.State of the Solar System Theories: A Mess 04/17/2003 The tally of recently discovered extrasolar planets exceeds 100, but not everyone is celebrating, says Dan Falk in the April 17 issue of Nature. Why the long faces? Extrasolar planets have peculiar properties, and our understanding of how planets form, which was incomplete even before the new data became available, now looks even shakier. The newly discovered bodies have strange, highly elliptical orbits. They are also far closer to their stars than equivalent planets in our Solar System. Amid the thrill of discovery, planetary scientists are wondering how to make sense of the processes that shaped these strange new worlds. Falk describes how the two competing models of planetary formation, the core-accretion model and the disk-instability model, both have problems, and neither can explain the highly elliptical orbits of many extrasolar planets, or why so many large ones are so close to the parent star. He can only hope that new instruments in Chile (Atacama Large Millimeter Array) and Hawaii (Sub-Millimeter Array) that can peer into stellar dust disks might provide answers within a decade. But for now, these new-found worlds dont look much like our planetary neighbours, and no one is quite sure why. We think students and the public should know that after over two centuries of the nebular hypothesis, planetary scientists are still at square one explaining our solar system by natural causes. If they thought finding extrasolar planets would complete the picture, it has only compounded the problems. Perhaps future observations will lend support to one hypothesis over another, but if history is any guide, the number of new puzzles will outpace simple answers. They certainly are not confident at this stage, as this article makes clear.Reports from Iraq 04/16/2003: Though somewhat off the topic of origins, a few stories coming out of Iraq are a study in contrasts, and a grim reminder that ideas have consequences. Read these and weep. How the prince lived. How the people lived. What the reporter who interviewed Saddam found. What the Marines found. What some people think about all this. Weeping is a good sign, even anger. Now, what are you going to do about it? Have you ever considered what people in 1945 must have thought when the unspeakable cruelties of the Holocaust became known? Did you ever prejudge the indifference some showed? Now its our turn. And remember, Iraq has been just one of many places around the world where people suffer unspeakable atrocities and are denied basic human rights. Personal or armed intervention may not always be possible, but anyone can do these: get informed, support those who can intervene, speak out, and pray.Gene for Speciation Found? 04/15/2003 What splits a species in two, such that reproductive isolation occurs? A team of Cambridge geneticists, writing in the April 14 preprints of the Proceedings of the National Academy of Sciences, thinks they have uncovered a gene in fruit flies that drives different species apart, making hybrids incapable of producing fertile or viable offspring. In the 1940s, Dobzhansky and Muller theorized how genes might diverge between two populations and become lethal to each other: Their theory envisions that during or after speciation different alleles will evolve in different species. These alleles can reach fixation by either positive selection or neutral drift, but during this period, there is no selection against potentially deleterious interactions with derived alleles that are evolving in other species. These deleterious interactions will be observed only in hybrids between the species.John Roote et al claim to have discovered a hybridization gene Hmr in fruit flies that keeps Drosophila melanogaster (the widely-studied species) from being able to produce fertile hybrids with others. The gene has diverged rapidly, they claim, between various species of Drosophila, at an extraordinarily high rate of amino acid substitutions, insertions, and deletions, such that crosses between species are either sterile or lethal. This hints at a mechanism that produces reproductive isolation; Population genetic analysis will be required to test the hypothesis, they caution, that the divergence of Hmr reflects positive selection, but our present results do strongly suggest that this divergence cannot be explained as nonfunctionalization of Hmr caused by a loss of selective constraint. Other clues suggest to them that the changes are not due solely to neutral drift (i.e., random substitutions due to mutations or copying errors), but are being acted on by natural selection in some way, and quickly: Our first glimpses of speciation genes therefore suggest that they may have the special property of rapid sequence divergence. So have they found the answer to speciation? Can one rapidly-evolving gene explain it? They map out the action items, in conclusion (emphasis added): These findings raise important questions about the mechanism of species incompatibilities. If the rapid evolution of speciation genes is found to be typical, it might suggest that multiple substitutions with synergistic effects are required before a gene becomes functionally diverged enough between species to cause a hybrid phenotype. Alternatively, a few substitutions, or even a single substitution, might be sufficient to create a hybrid incompatibility allele, with their high divergence rates reflecting the fact that many substitutions must occur before one has functional significance in hybrids. These possibilities can be addressed by investigating the mechanism of hybrid lethality by using the powerful genetic resources of D. melanogaster. Identifying the genes that interact with or are downstream of Hmr will also help to answer whether hybrid incompatibility genes are in general evolving rapidly.The paper is entitled, A rapidly evolving MYB-related protein causes species isolation in Drosophila. Judge: You may now question the witness. Prosecutor: Thank you, your honor. Mr. Roote, what led you to conclude this gene had evolved rapidly? (We found homologues in other species with numerous substitutions, insertions, and deletions.) And yet these genes were functional, correct? (Yes.) How did you know they were homologous? (Presumably they derived from a common ancestor.) How do you know they had a common ancestor? (Because they have these homologous genes.) I see. How did you calibrate the speed at which this gene diverged? (We used the molecular clock, the rate at which mutations accumulate.) And how is the molecular clock calibrated? (By invoking the time of the last common ancestor, and counting the changes since then.) In this exhibit, I show two family trees of arthropods from two scientists that differ radically in their placement and timing of the last common ancestor. Can you tell me which one I should use to calibrate the molecular clock?Origin of Sex: Queen of Evolutionary Problems 04/14/2003 Despite the suggestions given on the PBS Evolution TV episode Why Sex?, the origin of sex is still hard to explain in evolutionary terms, because it involves a high cost without a clear benefit. Now, according to a piece in the April 15 Current Biology, the conundrum got deeper. Some evolutionists have hypothesized that sex provides an advantage by purging the genome of debilitating mutations. Presumably, asexual organisms have a tougher time shedding mutations than sexual populations, who can dilute a mutation by half every time a couple mates. A tiny crustacean named Darwinula stevensoni, however, appears to have maintained its genomic integrity across long ages and widely separated habitats. This may be due to enhanced DNA repair mechanisms; so it not only avoids mutation load, but has the asexual benefit of passing 100% of its genome along. Reporter Nigel Williams remarks that there are now more than 20 hypotheses concerning the origin of sex. He calls it the queen of evolutionary problems. Williams leaves the problem unsolved, stating that if this crustacean has enhanced DNA repair, then these small crustaceans may have beaten sex at its own ubiquitous and influential game. If this is the queen of evolutionary problems, then the king is how you get life at all without intelligent design, and the joker is the evolutionary storyteller.Traffic Controls in the Cell Prevent Traffic Jams 04/14/2003 Cells have a variety of cargos that need shipping, including messenger RNA particles, mitochondria, endosomes, lipid droplets, and more. These are continually on the move in the cell, going from one part of the cell to another, where needed. They are carried along by molecular motors that move along tracks called microtubules that have a + (plus) end and a - (minus) end. Each transporter moves toward its specific polarity: kinesin moves toward plus, and dynein moves toward minus. Both motors can grab a piece of cargo simultaneously, but this creates a situation like a boxcar being pulled by engines facing opposite directions. How does the cell coordinate the movements? Is it a tug-o'war, or is there some switching action that coordinates the traffic? Apparently the latter. In the April 15 issue of Current Biology, Steven P. Gross of UC Irvine reviews todays understanding on the subject. Although much remains to be explained, a complex of proteins appears to act like springs to engage or disengage the transporter when necessary, as if putting the idle engine in neutral so the driving engine can have priority. In addition, additional regulation is needed to govern which direction has priority. The result is that even with one-way engines, interference is avoided, so that cargo can move both forward and backward on the track, and even reverse direction if the need arises. By removing these controls, scientists have been able to create traffic jams and pile-ups in a system that otherwise works in smooth coordination. All this, and no need for traffic reports every six minutes on the radio. How many commuters have any conception of the fact that deep inside their bodies, a transportation network vastly exceeding the freeway system of a large city, functions smoothly, night and day, without accidents? |