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If we have learned anything at all in a century and a half of evolutionary biology, it is that facile generalizations are dangerous. The evolutionary process finds a way to create exceptions to every model we propose. | ||||||||||||||||
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Next headline on: Human Body Politics and Ethics Origin of Life Bible and Theology Early Man Birds Terrestrial Zoology Cell Biology Darwin Amazing StoriesDarwin Debates Attract Rhetoricians, Some Pro, Some Not 08/31/2005 ![]() Nothing like a controversy to get people talking. Some understand the issues and speak with skill and style; some just like to be part of the excitement. Here are samples from the war of the words over evolution:
When the rhetoric flies, exercise sense, not sensationalism. Some get it right, some have no context. This debate has deep roots in history. Perpetuating buzzwords or labels is not going to make the debate over naturalism vs. design disappear. Caution: read news articles and editorials on this issue only with Baloney Detector engaged and in good working order but do read.Marvelous Puzzle: Enceladus South Pole Surface Less Than 1,000 Years Old 08/30/2005 ![]() Enceladus, a moon of Saturn smaller than the British isles (comparison image), has a region at the south pole that is less than 1,000 years old, and maybe only 10 years old. This conclusion, announced at Cassini science briefings in London August 30, is based on multi-instrument observations taken July 14 during the closest flyby ever of Enceladus (08/09/2005, 07/14/2005). Crystalline ice has been found in four 80-mile-long parallel canyons dubbed tiger stripes due to their appearance. Water ice has been observed venting into a plume of small particles from these cracks, which are noticeably warmer than the surrounding regions. Measurements from all the instruments aboard the Cassini spacecraft converge on the conclusion that Enceladus southern polar surface is young, probably active today. Two instruments detected icy particles coming from the south pole. The Ion and Neutral Mass Spectrometer (INMS) and the Cosmic Dust Analyzer (CDA) measurements reached a peak at closest approach (graph, flyby chart), showing that material is being emitted now, and probably accounts for at least some of the fresh material replenishing the E-ring around Saturn. The Magnetometer (MAG) confirmed the existence of this plume by watching its asymmetric influence on the magnetic field lines around Enceladus; the Ultraviolet Imaging Spectrometer (UVIS) arrived at the same conclusion. The Virtual and Infrared Mapping Spectrometer (VIMS) (picture) and Composite Infrared Spectrometer (CIRS, see article and picture) showed a temperature rise across the tiger-stripe cracks up to -279°F, almost 40° warmer than expected. Apparently this is warm enough to cause sublimation of ice from the surface. The crystalline nature of the ice constrains its age to 1000 years or less. Crystalline ice rapidly changes to an amorphous structure when exposed to solar radiation. Another odd thing about the tiger stripes is that each of them curves into a question mark shape at one end, all facing the same way (picture 1, picture 2). Could this be a rotational effect, or is it due to a massive flow from the west? The closest-approach image (picture and zoom-in movie) revealed boulders about 20m in size that New Scientist said could be ejecta from eruptions. That Enceladus should be erupting material today is puzzling to the planetary scientists for several reasons. For one, the north pole is heavily cratered and therefore looks much older; why would the south pole be active, when normally the equatorial regions are the warmest? (compare prediction vs. observation). Another puzzle is the comparison with Mimas, a moon of similar size. Mimas is heavily cratered with no activity, even though it was pummeled by a colossal impact at some time in the past and is subject to greater tidal stresses due to its proximity to Saturn. Finally, small bodies cool the fastest. A moon the size of Enceladus should long ago have lost all its internal heat and remained forever frozen solid. To account for the heat and resultant activity (03/04/2005), planetary geologists are constructing models combining radiogenic heat from a rocky interior and tidal heating from interactions with Saturn and other moons. So far, however, these energy sources seem to come up short by an order of magnitude or two (see New Scientist). This is a marvelous puzzle, said one scientist; another said that Enceladus is constantly evolving and getting a makeover. Enceladus joins a short list of bodies in our solar system where scientists have found internal activity, the press release said. That list includes Io (05/04/2004), Titan (06/09/2005, 05/18/2005, 04/08/2005), Triton (05/30/2002), Earth, and Venus (see Earths Ugly Sister Cant Get a Date, 08/16/2004). Most other solid planets and moons exhibit surface features that, while not active today, appear young (06/05/2003 commentary). The Cassini team expected that Enceladus would prove one of the prima donnas of the Saturn system. It appears that she delivered a stunning surprise of a performance. Sources: JPL, Cassini press release, NASA Cassini page, New Scientist, BBC News, the Planetary Society, EurekAlert and the Cassini Imaging Team. The latter contains polar projection maps, a graph and flyby chart, and three models attempting to explain the heating process. Scientists love a good puzzle, and being surprised is fun; we can all share the excitement of a new and baffling phenomenon. But what none of them seems to be asking is the obvious question: how could this moon be anywhere near 4.6 billion years old? Look at the size of those canyons 80 miles wide and 50 miles apart they speak of large-scale processes at work, not just minor eruptions. This revelation is just the latest in a long string of discoveries that challenge the consensus view of the age of the solar system. For all the flash and color of the model diagrams, New Scientist says that tidal heating and internal radioactivity are not anywhere near sufficient to drive the activity. Why not consider the possibility that Enceladus as well as the solar system that contains it is young.Back to School, Front to Darwinism Debate 08/30/2005 ![]() The national debate about how to teach origins in public schools continues to roil. Here are some recent developments:
If science were really so threatened by a few people using the D word design, the Darwinists wouldnt have to defend their pet story with loyalty oaths, signed statements, and discrimination. They could solve their little conflict with a little evidence. Thats where the wise advise aiming our eyes.Do You Belong in the Zoo? 08/29/2005 ![]() People are gawking at people in the London Zoo, each probably wondering what side of the cage they belong on. In one of the primate exhibits, eight scantily clad white people are on display, reports AP (see MSNBC and Yahoo). Wearing fig leaves pinned onto their swimsuits, they play, they scratch, they groom each other, they wave to the onlookers. The idea is to show that humans are nothing special, but just like other animals. Unlike the apes and chimpanzees in the other primate cages, however, the humans get to go home at night. The stunt is drawing visitors who had never visited the zoo. Some viewers were disappointed to find the humans wearing clothes; didnt fig leaves come from the Genesis tradition? they wondered. Children, confused by the message of the display, have been overheard asking, Why are there people in there? An apocryphal story has one of the chimpanzees asking, Am I my keepers brother? At least theyre using white people this time (see articles by Carl Wieland and Jerry Bergman). Mark Looy at Answers in Genesis couldnt keep silence any longer, especially when he had a Londoner on staff, Dr. Monty White, to interpret the zoos actions in light of Darwinian theory.Molecular Motors Galore: How Did They Evolve? 08/26/2005 ![]() Myosin is one of the cells little monorail motors that trucks cargo around the cell, pushes false feet into the surrounding environment, forces packages out the cell membrane, makes muscles move and wiggles hairlike cilia. Scientists reporting in Nature1 found twice as many varieties of myosin (37) than were previously known (17) and decided to plug them into the evolutionary tree of life and figure out how they diversified throughout eukaryotic lineages. Although they found many synapomorphies (apparent instances of convergent evolution), Richards and Cavalier-Smith think they reduced the diversity of myosins down to three ancestral types. They wrote, We conclude that the eukaryotic cenancestor (last common ancestor) had a cilium, mitochondria, pseudopodia, and myosins with three contrasting domain combinations and putative functions (emphasis added in all quotes). They did not elaborate, however, on how these mechanisms and functions arose in the hypothetical single-celled ancestor. Margaret Titus, commenting on this paper in the same issue of Nature,2 said, Analysis of their sequences in a wide range of organisms reveals an unexpected variety of domains, and provides insights into the nature of the earliest eukaryotes. In another molecular-machine story, three scientists found that the cellular powerhouse motors named ATP synthase come in pairs. Reporting in PNAS,3 they actually photographed pairs of the miniature machines an incredible feat, considering they are only about 12 nanometers tall and found them bridged together at 40° angles. They suspect that this arrangement helps in the formation of cristae (curved membranes within the mitochondria) and stabilizes the little rotary engines as they generate ATP: This complex is assumed to improve the efficiency of ATP synthesis by substrate-product channeling. The authors did not speculate on the evolution of the motors or of the larger structure that they call an ATP synthasome complex. Additional proteins and enzymes, whose functions are as yet unknown, appear to take part in the operation. 1Thomas A. Richards and Thomas Cavalier-Smith, Myosin domain evolution and the primary divergence of eukaryotes, Nature 436, 1113-1118 (25 August 2005) | doi: 10.1038/nature03949 2Margaret A. Titus, Evolution: A treasure trove of motors, Nature 436, 1097-1099 (25 August 2005) | doi: 10.1038/4361097a. Evolutionary theory is so useless. The first two scientists ought to be humbly standing in awe of cellular wonders at the fringe of our ability to comprehend them, and all they wanted to do was speculate about how machines built themselves by chance. Did Richards and Cavalier-Smith add any logical or observational support for evolution? Assuredly not. They merely assumed it from the start, then organized the observations into a presuppositional template. Could they delineate the actual mutations and selective forces that morphed one form into another? Could they tell how the original ancestral forms already highly complex emerged out of the primordial chemistry lab? Did they even for a moment consider the possibility that apparent design might represent actual design?Do Fossil Counts Match Sediment Counts? 08/25/2005 ![]() If evolution is true, the number of species coming and going should track the number of rock layers in which they are fossilized, at least roughly. The more sediments per unit time, the more new genera should arise within them. Shanan E. Peters (U of Michigan) decided to test this novel approach with marine fossils (the most abundant in the fossil record) over most of the geologic column, from Cambrian to Pliocene, and did indeed find a correlation. He wrote his conclusions in PNAS.1 Peters compared two databases: one that counted genera of marine organisms in the worldwide geologic column, and one that counted rock sections in the geologic column in the USA. (A section is a record of continuous sedimentation bounded by gaps, or unconformities.) First, he graphed genus richness against rock quantity; these measurements correlated well until the Cretaceous, when they diverged sharply. The divergence, he explained, could have been a statistical artifact of sampling called the pull of the recent; i.e., the tendency for recent epochs to be better represented than ancient ones. Thats OK, he explained; one would expect the correlations to be seen better at macro rather than micro scales. Second, he graphed first and last appearances of genera against the bottoms and tops of rock sections. These correlated fairly well for extinctions (r=0.75), but not as well for originations of genera (r=0.54 or less). This finding means, he tells us, that the average longevity of a genus in the fossil record is comparable with the average duration of a sedimentary section. In fact, the entire frequency distribution of genus longevities is remarkably similar to that of section durations. Third, he compared genus turnover with section turnover and also found similar positive correlation, though with some data points as prominent outliers. In his concluding discussion, he tried to explain what these correlations mean. These results demonstrate that the temporal distribution of genus first and last occurrences in the marine animal fossil record is intimately related to the temporal continuity and quantity of sedimentary rock. Determining why this result is the case is more challenging than demonstrating that it is so. (Emphasis added in all quotes.)Since the two databases (genus counts and section counts) were presumed as independent as two data sets that share the same timescale could possibly be, he felt the correlations, rough as they were, indicated something significant. Either the results were artifacts of preservation bias (the luck of the fossilization process), or had a common-cause relationship. The former, he argued, seems unlikely: Thus, if stratigraphic correlation and the shared timescale are the only reasons for statistical similarity, then virtually all temporal patterns derived from the geologic record must be little more than methodological artifacts of binning and correlation. This possibility seems extremely unlikely (although quantifying the magnitudes of the statistical contributions of these factors is very important). That being agreed, which explanation selection bias or common cause best explains the data? Assuming that macroevolutionary patterns derived from genus first and last occurrences have the potential to be meaningful in a biological sense, the task then becomes to explain why patterns in the genus fossil record are closely duplicated by analogous patterns in the sedimentary rock record. As discussed above, there are two possibilities, (i) preservation bias and (ii) shared forcing mechanisms (common cause).He showed that the latter possibility makes better predictions, but does admit one caveat: because only unconformity and rock quantity biases are being measured here, it is possible that facies biases and/or asymmetries in environmental preservation within sedimentary sequences are causing the stronger section-genus extinction correlation; i.e., the beginning and end of the story dont always reveal what happened in the middle. Nevertheless, he felt confident that taxonomists and geologists had not conspired to bias the conclusions: it seems unlikely that the work of hundreds of taxonomists has been so nonrandom as to render the survivorship patterns of >32,000 genera from across the tree of life little more than a quantification of the structure of the sedimentary rock record. Why, however, would the genus extinction count correlate with the end of the rock section better than the origination count correlate with the beginning? Aha, the common-cause hypothesis predicted it would. The answer is in the way evolution works: Under the common-cause hypothesis, however, genera are expected to originate early in a sedimentary basins history as new habitats and environments expand and to go extinct abruptly when environmental changes eliminate the basin environments altogether. Thus, similar average durations for sections and genera as well as corresponding peaks and troughs in rates of origination and extinction are expected. Interestingly, the common-cause hypothesis also predicts that the genus-section extinction correlation should be stronger than the genus-section origination correlation because genus extinction can match the timing of rapid environmental shifts that result in section truncation, whereas genus origination may not be capable of responding instantly to the macroevolutionary opportunities afforded by basin expansion. This possibility is sensitive to choice of timescale, but it is supported by analyses that find less empirical support for pulsed genus origination [i.e., punctuated equilibria] than for pulsed genus extinction at the same level of temporal resolution in the Phanerozoic.The remainder of Peters discussion delved into the meaning of these correlations for theories of environmental forcing of macroevolution and timing of mass extinctions. He favored gradualism over saltation for origination of species, and discounted the need for major catastrophes to explain extinction rates. He defended the challenging concept that much of the macroevolutionary history of marine animals is driven by processes related to the formation and destruction of sedimentary basins. If some evolutionists believe that extinctions and explosions of biological diversity can be forced by a meteorite impact, for instance, why not consider the possibility that macroevolutionary change can also be forced by slower geological changes? Thus, it would seem prudent to revisit some of the classic unifying hypotheses that are grounded in the effects of continually operating processes and to reevaluate seriously the extent to which unusual or episodic events are required to explain the macroevolutionary history of marine animals. In conclusion, he admitted that more work will need to be done to rule out taxonomic biases. These remain a potential obfuscator of macroevolutionary patterns in all global taxonomic databases, he says; though he has shown some correlation, he is not trying to push his point too far. Further quantifying the relationships between the large-scale temporal and spatial structure of the geologic record and the distribution of fossil occurrences within this structure will be important, he ended, in overcoming persistent sampling biases and in testing the extent to which common-cause mechanisms have dominated the macroevolutionary history of marine animals. 1Shanan E. Peters, Geological constraints on the macroevolutionary history of marine animals, Proceedings of the National Academy of Sciences USA, August 30, 2005, vol. 102, no. 35, 12326-12331, published online before print August 16, 2005, 10.1073/pnas.0502616102. This lengthy entry is exhibited here to show how evolutionists can fool themselves into thinking the observations support Charlies tall tale. In the first place, he used evolutionary assumptions to calibrate evolutionary assumptions: the common timescale of both databases is the geologic column, a theoretical arrangement of global sediments built on the assumption of evolution and millions of years. This is reminiscent of the joke about the church bell ringer who set his watch by the clock tower on the parliament building, only to find out that the clock tower maintenance man set his clock by the church bell. Second, the correlations are only marginally significant. His charts show severe outliers. Sometimes the anomalous data points have an important story to tell. Third, his use of gap-bound rock sections only concentrates on the beginning and ending of continuously-deposited sediments. In the old Dr. Seuss book The Cat in the Hat, the first and last pages of the book, showing the children contentedly at ease in a clean living room, belies all the chaos and commotion that occurred in the middle. Last, Peters trusted in the if you build it, they will come theory of evolution. He didnt explain how new genera of marine organisms would emerge when the sea level rose or fell; he just assumed that whenever organisms are given a safe haven, presto! macroevolution happens. In short, the evolutionary story rigged, controlled, operated and guaranteed the outcome of the entire analysis. Evolution is a self-fulfilling prophecy.Looking for Ethical Alternatives to Embryonic Stem Cells 08/24/2005 ![]() Pro-life advocates perked up their ears at the announcement of a new method that can produce stem cells without destroying embryos. National Geographic News and MSNBC News talked about the method, which uses skin cells and reprograms them to act like embryonic stem cells. Religion Journal thinks the ethical debate over stem cells may be over. This story illustrates the need for conservatives who respect the sanctity of life to keep boundaries around maverick scientists motivated by dollars more than ethics. Researchers would not be looking for alternatives to grinding up human embryos if it werent that there were enough people outraged at the ethical malfeasance of killing one life to save others. The selfish motives of the stem-cell pushers became evident when some reporters showed them worrying that this discovery might reduce funding for embryonic stem cell research.Darwins Finches Evolve Back and Forth 08/24/2005 ![]() Whats new on the Galápagos? For those needing an update on Darwins famous finches, the researchers who have spent the most time studying them Peter and Mary Grant (Princeton) wrote a Quick Guide in Current Biology1 in question-and-answer format. Well skip the introductory material about how the birds got named after Darwin, and what makes them special in the history of evolutionary thought, to see if the Grants have any evidence that they have, indeed, evolved. The key question is: Are Darwins finches still evolving? An often asked question may be phrased as follows: what can be said about evolution if it all happened in the past, for surely understanding where our biological diversity came from is then a mixture of scientific inference and inspired guesswork, almost impossible to verify? Imperceptibly slow evolution encourages such skepticism. In the Origin of Species, Darwin wrote We see nothing of these slow changes in progress until the hand of time has marked the lapse of ages.Moreover, when asked about finch genomics, they claimed the genes of the finches are evolving, though the evidence is only preliminary: The molecular analysis of finch beaks has only just begun. In addition to this functional genetic study, molecular markers in the nuclear and mitochondrial genome have been used to estimate the phylogeny of the finches. With some exceptions they support the traditional grouping of the species on the basis of their plumage and beak characteristics. Molecular markers have also been used to track the exchange of genes between species that interbreed, albeit rarely, and the finding is dramatic. They show a pair of species on Daphne in a state of flux, at present converging genetically and morphologically, having diverged strongly in the past. This nicely captures the evolutionary dynamism that Darwins finches display to an unusual degree.Yet if they diverge then converge back to where they were before, is that really evolution? The Quick Guide moves on, leaving that question unasked and unanswered. 1Peter R. Grant and B. Rosemary Grant, Quick Guide: Darwins Finches, Current Biology, Volume 15, Issue 16, 23 August 2005, Pages R614-R615. There you have it: the worlds leading authorities on the beaks that made Charlie famous, and they dont add a thing to what young-earth creationists already believe. The Grants merely repeated what is already admitted by intelligent-design researchers in the films Unlocking the Mystery of Life and Icons of Evolution; any observed changes are mere oscillations about a mean. These poor devoted people have measured beaks for over 30 years and have not found any persistent directional changes nor could they be expected to in one human lifetime. They even admit that today the birds remain interfertile and so have not really undergone speciation after however long they have lived on these islands. Yet they expect us to think that it is a scientifically sound inference to extrapolate their data, which, in evolutionary terms, constitute noise, into long-term directional trends.Your Brain Has Perfect Pitch 08/23/2005 ![]() Scientists have a knack for asking questions about things most of us take for granted. The whole orchestra tunes up to an A note from the oboe but how do our brains tell that all the different sounds are the same pitch? asks Robert J. Zatorre in Nature.1 This is a puzzling question to neurologists. Theres more, as Zatorre illustrates with a Disney story: As Pythagoras knew, if you pluck a string, it will vibrate in its entire extent, as well as in halves, thirds and so on, and each of those vibrational modes will result in a separate harmonic frequency. Yet we usually perceive the pitch as corresponding to the lowest of these, which is the fundamental. For a simple demonstration of the missing fundamental effect, pick up a phone. Most telephone lines cut off the lower frequencies, resulting in a slightly tinny sound, yet the fundamental pitch does not change; a male voice does not sound like Mickey Mouse. The brain seems to figure out the missing pitch. (Emphasis added in all quotes.)Is this just learned behavior, or what? Apparently not. Researchers working with marmosets have found neurons that are pitch-sensitive: Bendor and Wang studied the auditory cortex (the region of the brain that enables perception of sound) in the marmoset monkey. They show that there are neurons in this region that respond in essentially the same way to a variety of sounds that all have the same fundamental but do not share any frequencies. For example, a neuron that responds to 200 hertz also responds to the combination of 800, 1,000, and 1,200 hertz because all correspond to the same fundamental. This effect is unusual because neurons usually respond only within their receptive field, which is typically a narrow range of frequencies. The marmoset neurons, however, responded not only to frequencies in their receptive fields, but also when there was no frequency within the receptive field but the other frequencies in the stimulus were harmonically related to the missing one. This property makes psychologists happy, because it provides evidence (if not yet a mechanism) for perceptual constancy. These neurons respond to an abstract property pitch derived from, but not identical to, physical sound features. Presumably, therefore, it is thanks to such neurons that we can follow a tune as the instruments change.That leads to an evolutionary follow-up question, which Zatorre attempts to answer: One might wonder why marmosets need such a system, given that they dont spend much time listening to iPods. But periodic sounds are important in the natural environment because they are almost exclusively produced by other animals, and so pitch is a good cue to segregate these sounds from background noise. Marmosets are highly vocal creatures, and the development of pitch-sensitive neurons would also be central to communication. From an evolutionary perspective, these abilities could be seen as precursors to human pitch perception, which has led to our unique development of music and is similarly crucial for speech.Thats that for now; he quickly changes the subject: Now that we know that there are pitch-sensitive neural units, we have to discover how they work. He has a long list of unanswered questions: How does the ear keep the information intact through the transformations between eardrum and cochlea? How does the brain extract details from the overall fabric of sound? What are the inputs to these pitch-sensitive neurons? are they hierarchical, or built up from multiple inputs from other structures in the brain? Do inputs from the higher cognitive regions of the brain participate? Are these neuronal properties hard-wired or learned? The list of answers is shorter: we dont know. 1Robert J. Zatorre, Neuroscience: Finding the missing fundamental, Nature 436, 1093-1094 (25 August 2005) | doi: 10.1038/4361093a. This article almost earned a Dumb award for its useless evolutionary speculations. Zatorre committed the plostrum ante equum fallacy (cart before the horse), assuming that necessity was a sufficient mother of invention. Aside from the empty evolutionary fluff, though, the article underscored a fascinating aspect of hearing that merely hints at the engineering necessary to make it work. Music doesnt make evolutionary sense because it is a gift of God. If Bach appreciated that fact, how much more so should modern anatomists, physiologists and neurologists.Origin of Life: How Dry I Am? 08/23/2005 ![]() Stephen Benner (U of Florida) has stopped looking for life in water. A researcher into the evolutionary origin of life, he understands that water is a terrible solvent for life not life as we know it today, he means, but life at the beginning. This sounds strange, considering most astrobiologists believe in a follow the water approach to finding life in space. In Nature,1 he explained: Benner points out that water is generally not a good solvent for doing organic chemistry which is, in the end, what life is all about. For one thing, water is rather reactive, tending to split apart the bonds that link the building blocks of biomolecules together. It readily breaks peptide bonds, for example, as well as many of the bonds in nucleic acids, such as RNA. The structure of RNA screams I did not arise in water! Benner asserts. He says that in about four out of five cases, synthetic organic chemists will avoid using water as a solvent. (Emphasis added in all quotes.)Benner shared his ideas at a conference in Italy earlier this year. Philip Ball investigated his ideas in the article, but puzzled over what Benner said and what we know about how life utilizes water: But of course organic chemists arent usually trying to create life. Water has many properties that seem indispensable for the functioning of proteins and cells. It is an excellent solvent for ions, for example crucial for nerve signalling, enzymatic processes, biomineralization and the behaviour of DNA. It is also a master of weak intermolecular interactions such as hydrogen bonds and hydrophobic forces. The latter play a central role in protein folding and protein-protein interactions, whereas the former often act as bridges between protein binding sites and their substrates. And waters ability to absorb and lose heat without undergoing a large temperature change provides thermal cushioning, shielding cells and organisms from wild temperature swings.Because water is an enemy at the origin of life but an indispensable friend for sustaining it, chemical evolutionists have a conundrum on their hands. As an escape, they are asking what if questions about whether life could have arisen in other solvents. Asking such what if questions might seem strange to biologists and chemists, but it is far more common in cosmology or physics [see 08/16/2005]. For cosmologists, the physical Universe seems to be precariously fine-tuned to make life possible. For example, the fine-structure constant, which determines the strength of electromagnetic interactions, is not fixed by any known fundamental theory; and yet if it was ten times larger, stable atoms could not exist....Others at the conference thought Benner was putting the cart before the horse: life on Earth is adapted to water rather than the other way round, they agreed. Benner, meanwhile, beset by the problems with RNA and proteins in water, is going to investigate uncharted territory: dry, frozen worlds with liquid methane, perhaps, like Titan (08/09/2005, 01/21/2005), or ones of his own making: Benner is participating in a US National Academies panel funded by NASA that is looking at possible alternative chemistries for life, and which he hopes will identify research directions that funding agencies can pursue. He believes that researchers should aim high to create life forms that do not reproduce the chemistry that is found on Earth. In other words, if we cant easily get to other worlds, we should build them here. 1Philip Ball, Water and Life: Seeking the Solution, Nature, 436, 1084-1085 (25 August 2005) | doi: 10.1038/4361084a. Steven Benner should know better. He knows more than most evolutionists how many and intractable are the problems with chemical evolution; the problems are so bad, in fact, that he joked that they are almost enough to make one consider becoming a creationist (see 11/05/2004 entry). Now that is really bad to a Darwinist! Nothing could be worse.Paleoanthropology: Start Over? 08/22/2005 ![]() The September issue of National Geographic, featuring the African continent, has arrived in homes. On page 1, Joel Achenbach of the Washington Post wrote about the quest for early man, asking, Are we looking for bones in all the right places? The bulk of the article describes the messy story of human origins. It used to be clean-cut, he said, but no longer: Scientists are good at finding logical patterns and turning data into a coherent narrative. But the study of human origins is tricky: The bones tell a complicated story. The cast of characters keeps growing. The plot keeps thickening. Its a heck of a tale, still unfolding.That represents the bulk of the article: the simple picture is gone, we dont know who begat whom, we have no fossils of chimpanzees, the family tree is full of dead ends, and we may be trying too hard to tell a story from too few bones. Achenbach quotes Dan Lieberman of Harvard: Were not doing a very good job of being honest about what we dont know. Sometimes I think were trying to squeeze too much blood out of these stones. Achenbach also contrasts the study of human evolution with the classical hard sciences: Earth doesnt yield a perfect database. Still, its our scientific impulse to impose parsimonious explanations on complex problems in the same way that Newton realized that the fall of the apple and the motion of the planets were governed by the same simple force called gravity. But the process of evolution cant be observed like the fall of an apple. Lifedespite all the efforts of modern scienceis messy.One might be tempted to conclude, therefore, that the field is open to alternative explanations. Why, then, does Achenbach put this statement in the middle of his article? The central fact of human evolution is a givenhumans descended from a primate that lived in Africa six or seven million years agoand those who would doubt evolution are arguing against the entire enterprise of science. The basics are established, he claims; its only some key details that are unknown. Is it any wonder why Achenbach wins Stupid Evolution Quote of the Week? Look at what he did. He demolished everything most of us were taught as evolutionary fact years ago. He admitted that the whole picture is a mess of disconnected, confusing pieces. He admitted that no one can make sense of it. He admitted that paleoanthropology is not in the same ballpark as Newtons hard science, and why?because the process of evolution cant be observed like the fall of an apple. There arent enough ape bones, there arent enough human bones, and there arent enough bones of anything in between that is not controversial. On top of all that, we might even just be imposing our own preconceptions on the data! He quotes someone who casts doubt on the honesty of paleoanthropologists. That seasoned veteran of the science of paleoanthropology believes the researchers are trying to squeeze too much blood out of their bones.I.D. vs. Evolution Rhetoric Continues Unabated 08/22/2005, updated 08/24/2005 ![]() The surge in articles and editorials about intelligent design vs. evolution, prompted by President Bushs remarks (08/13/2005) often seems to track the political philosophy of the person or group: Republican vs. Democrat, conservative vs. liberal but not always. Recent salvos:
The wording may seem subtle but is significant. Anti-ID reporters are determined to portray intelligent design as inherently religious, so they employ the word supernatural to make their point: See? they gloat, hammerlocking their straw man; This cant be science, because its about the supernatural! But if the reference is to intelligent causes, those are already employed in scientific explanations in many fields. Science can investigate whether the cause was planned or unplanned without making any statements about who the Planner was or what the motive for the design was: this is done all the time in archaeology and criminology, for instance even in SETI itself, which makes DeVores position all the more ironic. Caught in a logical trap, all she can do is fall back on arguments from authority and bandwagon.You Otter Hair How Otters Keep Warm 08/22/2005 ![]() While on a sabbatical exploring Isle Royale National Park, John Weisel (U of Pennsylvania) decided to collect hair from various mammals. He found otter fur to be particularly interesting, says a press release from U of Penn Health System. Since otters dont have a layer of fat, he wondered, how do they keep warm in the icy water? Scanning electron microscopy showed the secret: the hairs fit together like tongue-and-groove woodwork: They found that the cuticle surface structure of the underhairs and base of the less-abundant guard hairs are distinctively shaped to interlock, with wedge-shaped fins or petals fitting into wedge-shaped grooves between fins of adjacent hairs (emphasis added). Click on the micrograph for additional photos and diagrams of how these hairs interlock. Not much on a mammals body seems simpler than hair, but like everything else in living things, simplicity evaporates on closer inspection. Not only are these hairs shaped just right to produce a tight, insulating pattern, but the blueprint has to be encoded in DNA and transcribed by the cellular construction factory according to spec, and extruded from each hair follicle at the right time, with the right shape, the right color and the right length. Lecturer Dr. David Menton can keep an audience entranced for an hour about the wonders of hair. The structural details on the micro level are necessary to produce the macro result: a sleek, playful otter that makes a living in cold water. It doesnt take much water to keep a daughter otter happy. Two pints makes one cavort.Why Mathematical Formalism Eludes Evolutionary Theory 08/19/2005 ![]() An important mathematical tool used by evolutionists has been discredited. To study life history evolution (i.e., the changes over time in a populations reproductive age, maximum size, age at death, etc.) evolutionists have relied on Charnovs concept of life history invariants. These invariants, which are dimensionless ratios of two life history traitsfor instance, age at maturity and average length of life, according to Gerdien de Jong writing in Science,1 have been a staple of evolutionary models, providing generalizations leading to an understanding of universal life history strategies. Now, warns de Jong about work by Nee et al. in the same issue,2 the principal method of detecting life history invariants has been called into question. The authors have determined that the approach is misleading, throwing the very existence of the concept into doubt. (Emphasis added in all quotes.) Ratios can fall on a straight line when plotted, suggesting a mathematical relationship, but Nee et al. have demonstrated that the relationships are figments of the method and not necessarily real. The same data plotted between groups of animals might yield a straight line, for instance, but when plotted within isolated groups of animals can yield lines offset from one another. The regression analysis is therefore misleading, de Jong says. The same problem can exist within other biological models. Are the patterns real, therefore, or contrived? Are they meaningful in evolutionary terms? Life history evolution is not the only field where invariants or universal constants are proposed. The Universal Temperature Dependence of metabolism proposal asserts that the metabolism of all organisms can be described by a single equation. Scaling laws (as, for instance, basic metabolic rate scale as mass to the power 3/4) are called universal over all life. This hankering for universal explanations has been criticized not only on technical grounds but also for ignoring biology and the variation between organisms. Interesting biology might not be in life history invariants but in biological variation.De Jong illustrates, for example, that two species of fish in the same habitat can have completely different ratios of sex to social rank. De Jong doesnt go so far as to argue that it is a waste of time to look for mathematical relationships in biology, just that We should be wary of treating an average across species as an explanatory general life history invariant. 1Gerdien de Jong, Evolution: Is Invariance Across Animal Species Just an Illusion?, Science, Vol 309, Issue 5738, 1193-1195, 19 August 2005, [DOI: 10.1126/science.1117591]. 2Nee et al., The Illusion of Invariant Quantities in Life Histories, Science, 2005 309: 1236-1239. Evolutionists desperately want their theories to be considered scientific, but the language of science is mathematics. They should recall the difference between the hard sciences and biology, as expressed by the Harvard Law: Under the most rigorously controlled conditions of pressure, temperature, volume, humidity, and other variables, the organism will do as it *@#&! well pleases. The deception is even worse when evolutionary psychologists measure human behavior according to Koestlers Ratomorphic Fallacy, treating people like lab rats, or when they try to describe altruism, whether in humans or bacteria, in terms of the equations of game theory. One of the ugliest of recent examples involved anthropologists trying to measure the evolution of anti-Semitism (see 07/19/2005).Saddle Up Your Algae: Scientists Harness Flagellar Motors 08/19/2005 ![]() 1805: Beast of burden of choice: oxen. 2005: Beast of burden of choice: algae. Science Now reported an unusual item: scientists have learned how to hitch their loads to a single-celled green alga named Chlamydomonas reinhardtii (see Yale description). Researchers are actually calling their little teams micro-oxen. Scientists are increasingly interested in harnessing biological motors for use in micro- and nanotechnology, but recent research has mainly involved taking moving parts out of cells and adapting them for use elsewhere. Its a complicated process that can require protein engineering. So, chemist Doug Weibel of Harvard University in Cambridge, Massachusetts, and colleagues wondered if they could simply use an intact organism as a beast of burden instead. (Emphasis added in all quotes.)This alga contains whiplike flagella that propel them through liquid like motorized paddleboats (see U of Wisconsin description). These algae are very reliable, Weibel said. See also the BBC News report. In other flagellum news, Howard Berg of Harvard, writing in Current Biology,1 described how bacterial flagella (the rotary kind) receive feedback from the environment: the flagellum senses wetness, he reported. The wetness of the environment affects antagonistic regulatory proteins that control flagellum production. Research by Q. Wang et al. found that a suppressor is pumped out of the cell by the flagellar transport apparatus once assembly of the basal part of the flagellum is complete, Berg said. What for? This prevents the cell from wasting energy on flagellin synthesis when this protein cannot be put to use. The scientists sprinkled a little water on dry colonies for 90 seconds and, sure enough, got them to produce more and longer flagella that exhibited normal swarming behavior. Berg describes it: Swarming is a specialized form of bacterial motility that develops when cells that swim in broth are grown in a rich medium on the surface of moist agar. The cells become multinucleate, elongate, synthesize large numbers of flagella, secrete surfactants and advance across the surface in coordinated packs. 1Berg, Howard, Swarming Motility: It Better Be Wet, Current Biology, Volume 15, Issue 15, 9 August 2005, Pages R599-R600. The intelligent design movement could get a load of this. It was amazing enough that some flagella are built like high-tech rotary motors. For humans to harness that power and use it underscores the claim that these really are molecular machines. Its there; it works; why reinvent the wheel?Do Emperor Penguins Know the Meaning of True Love? 08/19/2005 ![]() The nature film sensation March of the Penguins is capturing the public imagination because of its portrayal of emperor penguins in almost anthropomorphic visions. Strutting upright in their feathery tuxedos, these Antarctic seabirds seem almost human: they love, they walk, they sacrifice, they grieve over the loss of a chick, they endure hardship bravely, they rejoice at a family reunion. Its a bit over the top, reports Hillary Mayell for National Geographic News. She quotes biologists who cast doubt on whether penguins can experience true feelings. Penguins respond to hormones, biologists tell us, and their social behavior is instinctive. Still, the movie is worthwhile, the article confesses; the simplistic portrayal is useful, helping make some aspects of the life cycle of penguins more accessible to the general public. Mayell is right about the fallacy of imputing human emotional and moral qualities to birds. Still, birds are among the smartest of animals (03/23/2004, 02/17/2004, 08/09/2002). Who could know what they think and feel without becoming a birdbrain? (Remember, that is a compliment, not an insult02/01/2005). To believe that such behaviors are mere emergent properties of matter in motion seems inadequate. In evolutionary terms, animal behaviors that look playful or emotional seem senseless in a world of survival, and evolutionists are at a loss to explain them (03/24/2005). Maybe the fact that we humans can relate to the cries, chirps, and behaviors of emperor penguins indicates that there is, at some level, a non-material element to their ontology, a kind of psyche. While avoiding the fallacy of personification, we must also not commit the fallacy of reductionism.From Emperors to Monarchs.... 08/19/2005 ![]() If lion is king, and penguin is emperor, who would have thought a dainty insect would be monarch? EurekAlert posted a story earlier this month too good to pass up: monarch butterflies follow the light ultraviolet light to their breeding grounds. Scientists at Hebrew University, working with monarchs in a specially-designed flight simulator (see 05/09/2005, 07/09/2002), found that UV light was the key to keeping them on course. But thats not all: Further probing revealed a key wiring connection between the light-detecting navigation sensors in the butterflys eye and its brain clock, the article states. Thus, it was shown that input from two interconnected systems UV light detection in the eye and the biological clock in the brain together guide the butterflies straight and true to their destination at the appointed times in their two-month migration over thousands of miles/kilometers (emphasis added). Think how tiny a butterfly brain is to store that kind of programming. Next headline on: Terrestrial Zoology
Italy Going Soft on Darwinism
08/19/2005
The Darwinian theory of evolution by natural selection is the unifying principle of the biological sciences. Unfortunately in the Italian academic system, evolutionary biology is not acknowledged as an independent research area, so no faculty positions in evolutionary biology can be established, and most students hear only a brief summary of evolutionary theory in the final hours of their introductory zoology, paleontology, or genetics courses. To make matters worse, during the past two years, several creationist organizations have been publicly attacking the teaching of evolutionary theory. (Emphasis added in all quotes.)Its time to take action, says the Italian Society for Evolutionary Biology. Last year, they established the Coordinamento Italiano dei Biologi Evoluzionisti CoEvol for short to both strengthen collaborations between Italian evolutionists and to improve the teaching of evolution in Italy and to increase the involvement of undergraduate and graduate students in evolutionary studies. Activities include a new cyber-journal club allow evolutionists to discuss recent papers, annual meetings, and the announcement of the new Italian Society for Evolutionary Biology. More significantly, CoEvol hopes to become a lobby group that will foster collaboration among Italian evolutionary biologists in Italy and abroad and represent our interest in making evolutionary biology a priority in the Italian educational system. They have established a website: www.coevol.org. 1Announcements, Letter from the Italian Society for Evolutionary Biology, The American Naturalist, Vol. 166, Sept. 2005, pp. i-ii. Today, class, we will learn about the evolution of the pizza. The pizza was not created by intelligent design, as those rascally creationists allege. Instead, it emerged out of the primordial dough. Over millions of years, it became just one species of Italian food on the evolutionary Cuisine of Life, with spaghetti, linguini, tortellini and macaroni branching off early and forming the Pasta Kingdom, incorporating parmesan by lateral cheese transfer. Some theorists believe that pepperoni was once a free-living organism that became incorporated into pizza as an endosymbiont during the Prosciutto epoch of the Paleocarne Era. The pizza class experienced a rapid diversification into many forms on the North American continent, as the Italian fast-food restaurant niche opened after the last Ice Cream Age. This stimulated an explosive period of adaptive radiation, producing the Round Table family, the Shakeys family, and the Chuck E. Cheese family, among others. The microwave pizza, with no phylogenetic connection to the old-world pizzas of the Italian peninsula, provides a striking example of convergent evolution....Meteorite Impacts Solar System Theories 08/18/2005 ![]() A study partly funded by NASA and published in Nature1 has thrown a monkey wrench into theories of the origin of the solar system, according to a press release from the University of Toronto. Small grains of minerals called chondrules in two meteorites are young too young to have been formed in the assumed primordial solar nebula. When Alexander Krot and Yuri Amelin dated these chondrules, they found them too young to have formed at the beginning of the solar system. They postulate that heat from a collision much later might have formed them. It soon became clear that these particular chondrules were not of a nebular origin, Amelin said. And the ages were quite different from what was expected. It was exciting. 1Krot et al., Young chondrules in CB chondrites from a giant impact in the early Solar System, Nature 436, 989-992 (18 August 2005) | doi: 10.1038/nature03830. By young, Amelin and Krot are not claiming really young, but only a few millions less than billions: some 5 million years after the assumed birthday of the solar system, when meteorites were supposed to have formed. They exaggerate this birthdate to five significant figures: 4.5672 plus or minus 0.0007 billion years ago. With such contrived precision (see 06/05/2003 entry), Amelin and crew feed the Age of the Solar System (q.v. acronym) Myth. The rest of the scientific community falls in line, never questioning these ages. Here, we see that Dr. Moyboy himself ("millions of years, billions of years") has found an anomaly that allows him to throw in a thickening to the plot and get more fame in Nature. If this helps solar system theorists question their assumptions a little, thats a modicum of progress. Does it demonstrate that these two chondrules really are 4.5627 +- .0005 and 4.5628 +- 0.9 billion years old? Better read the caveats at the end of their paper:Fossil Brachiopod Shows Soft Part Details 08/18/2005This formation event [the hypothetical impact that formed the chondrules] has probably homogenized radionuclides in chondrules and metal of the CB chondrites, and reset short-lived radiogenic isotope systems.... For establishing consistent Solar System chronology, these chronometers have to be linked together and tied to an absolute timescale. Most meteorites are made of components formed at different time, and/or experienced complex and prolonged post-formation metamorphic history, and are not suitable for linking short-lived chronometers. In contrast, the correlated studies of multiple short-lived isotope systems in CB chondrites can potentially test the consistency among them and provide a tie to an absolute timescale, which will be an important step towards the unified timescale of the earliest Solar System. (Emphasis added.)With such wheeling and dealing going on behind the scenes, would you trust a resultant date to five significant figures? If so, try Madame Bluffys panacea potion. She mixed a pinch of bat wing, a smidgeon of spider eye and a handful of shredded Amanita mushroom gill in a solution of approximately half goat milk and half vodka. She guarantees it 99.263 +- .004% effective in the treatment of warts, goiter, acid reflux and toenail fungus. ![]() American and British paleontologists described in Nature1 the discovery of nearly complete brachiopods with calcified soft parts intact. They exhibited intricate details never before seen in fossils of these organisms, sometimes called lamp shells. Brachiopods, a type of marine animal that attached itself to the sea floor with a pedicle or stalk, were very abundant in the Cambrian, but are rare now |