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oldmike
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« Reply #105 on: 19 December 2017, 14:46:17 PM »

Creationist Fallacies.

2. Natural selection is based on circular reasoning: the fittest are those who survive, and those who survive are deemed fittest.

 “Survival of the fittest” is a conversational way to describe natural selection, but a more technical description speaks of differential rates of survival and reproduction. That is, rather than labeling species as more or less fit, one can describe how many offspring they are likely to leave under given circumstances. Drop a fast-breeding pair of small-beaked finches and a slower-breeding pair of large-beaked finches onto an island full of food seeds. Within a few generations the fast breeders may control more of the food resources. Yet if large beaks more easily crush seeds, the advantage may tip to the slow breeders. In pioneering studies of finches on the Galpagos Islands, Peter Grant and Rosemary Grant of Princeton University observed these kinds of population shifts in the wild.
The key is that adaptive fitness can be defined without reference to survival: large beaks are better adapted for crushing seeds, irrespective of whether that trait has survival value under the circumstances.
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« Reply #106 on: 20 December 2017, 14:17:45 PM »

Creationist Fallacies.

3. Evolution is unscientific because it is not testable or falsifiable. It makes claims about events that were not observed and can never be re-created.

This blanket dismissal of evolution ignores important distinctions that divide the field into at least two broad areas: microevolution and macroevolution. Microevolution looks at changes within species over time—changes that may be preludes to speciation, the origin of new species. Macroevolution studies how taxonomic groups above the level of species change. Its evidence draws frequently from the fossil record and DNA comparisons to reconstruct how various organisms may be related.

These days even most creationists acknowledge that microevolution has been upheld by tests in the laboratory (as in studies of cells, plants and fruit flies) and in the field (as in the Grants' studies of evolving beak shapes among Galpagos finches). Natural selection and other mechanisms—such as chromosomal changes, symbiosis and hybridization—can drive profound changes in populations over time.

The historical nature of macroevolutionary study involves inference from fossils and DNA rather than direct observation. Yet in the historical sciences (which include astronomy, geology and archaeology, as well as evolutionary biology), hypotheses can still be tested by checking whether they accord with physical evidence and whether they lead to verifiable predictions about future discoveries. For instance, evolution implies that between the earliest known ancestors of humans (roughly five million years old) and the appearance of anatomically modern humans (about 200,000 years ago), one should find a succession of hominin creatures with features progressively less apelike and more modern, which is indeed what the fossil record shows. But one should not—and does not—find modern human fossils embedded in strata from the Jurassic period (65 million years ago). Evolutionary biology routinely makes predictions far more refined and precise than this, and researchers test them constantly.

Evolution could be disproved in other ways, too. If we could document the spontaneous generation of just one complex life-form from inanimate matter, then at least a few creatures seen in the fossil record might have originated this way. If superintelligent aliens appeared and claimed credit for creating life on Earth (or even particular species), the purely evolutionary explanation would be cast in doubt. But no one has yet produced such evidence.
New species evolve by diverging away from established ones and acquire sufficient differences to remain forever distinct. Credit: Science Picture Company Getty Images
It should be noted that the idea of falsifiability as the defining characteristic of science originated with philosopher Karl Popper in the 1930s. More recent elaborations on his thinking have expanded the narrowest interpretation of his principle precisely because it would eliminate too many branches of clearly scientific endeavor.
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« Reply #107 on: 21 December 2017, 14:49:28 PM »

Creationist Fallacies

4. Increasingly, scientists doubt the truth of evolution.

No evidence suggests that evolution is losing adherents. Pick up any issue of a peer-reviewed biological journal, and you will find articles that support and extend evolutionary studies or that embrace evolution as a fundamental concept.
Conversely, serious scientific publications disputing evolution are all but nonexistent. In the mid-1990s George W. Gilchrist, then at the University of Washington, surveyed thousands of journals in the primary literature, seeking articles on intelligent design or creation science. Among those hundreds of thousands of scientific reports, he found none. Surveys done independently by Barbara Forrest of Southeastern Louisiana University and Lawrence M. Krauss, now at Arizona State University, were similarly fruitless.

Creationists retort that a closed-minded scientific community rejects their evidence. Yet according to the editors of Nature, Science and other leading journals, few antievolution manuscripts are even submitted. Some antievolution authors have published papers in serious journals. Those papers, however, rarely attack evolution directly or advance creationist arguments; at best, they identify certain evolutionary problems as unsolved and difficult (which no one disputes). In short, creationists are not giving the scientific world good reason to take them seriously.

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« Reply #108 on: 23 December 2017, 0:18:58 AM »

Creationist Fallacies

5. The disagreements among even evolutionary biologists show how little solid science supports evolution.

Evolutionary biologists passionately debate diverse topics: how speciation happens, the rates of evolutionary change, the ancestral relationships of birds and dinosaurs, whether Neandertals were a species apart from modern humans, and much more. These disputes are like those found in all other branches of science. Acceptance of evolution as a factual occurrence and a guiding principle is nonetheless universal in biology.

Unfortunately, dishonest creationists have shown a willingness to take scientists' comments out of context to exaggerate and distort the disagreements. Anyone acquainted with the works of paleontologist Stephen Jay Gould of Harvard University knows that in addition to co-authoring the punctuated-equilibrium model, Gould was one of the most eloquent defenders and articulators of evolution. (Punctuated equilibrium explains patterns in the fossil record by suggesting that most evolutionary changes occur within geologically brief intervals—which may nonetheless amount to hundreds of generations.) Yet creationists delight in dissecting out phrases from Gould's voluminous prose to make him sound as though he had doubted evolution, and they present punctuated equilibrium as though it allows new species to materialize overnight or birds to be born from reptile eggs.

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« Reply #109 on: 23 December 2017, 21:28:03 PM »

More Creationist fallacies:

6. If humans descended from monkeys, why are there still monkeys?

This surprisingly common argument reflects several levels of ignorance about evolution. The first mistake is that evolution does not teach that humans descended from monkeys; it states that both have a common ancestor.

The deeper error is that this objection is tantamount to asking, “If children descended from adults, why are there still adults?” New species evolve by splintering off from established ones, when populations of organisms become isolated from the main branch of their family and acquire sufficient differences to remain forever distinct. The parent species may survive indefinitely thereafter, or it may become extinct
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« Reply #110 on: 13 February 2018, 1:06:34 AM »

“Creation science” is a contradiction in terms. A central tenet of modern science is methodological naturalism—it seeks to explain the universe purely in terms of observed or testable natural mechanisms. Thus, physics describes the atomic nucleus with specific concepts governing matter and energy, and it tests those descriptions experimentally. Physicists introduce new particles, such as quarks, to flesh out their theories only when data show that the previous descriptions cannot adequately explain observed phenomena. The new particles do not have arbitrary properties, moreover—their definitions are tightly constrained, because the new particles must fit within the existing framework of physics.

In contrast, intelligent-design theorists invoke shadowy entities that conveniently have whatever unconstrained abilities are needed to solve the mystery at hand. Rather than expanding scientific inquiry, such answers shut it down. (How does one disprove the existence of omnipotent intelligences?)

Intelligent design offers few answers. For instance, when and how did a designing intelligence intervene in life's history? By creating the first DNA? The first cell? The first human? Was every species designed, or just a few early ones? Proponents of intelligent-design theory frequently decline to be pinned down on these points. They do not even make real attempts to reconcile their disparate ideas about intelligent design. Instead they pursue argument by exclusion—that is, they belittle evolutionary explanations as far-fetched or incomplete and then imply that only design-based alternatives remain.

Logically, this is misleading: even if one naturalistic explanation is flawed, it does not mean that all are. Moreover, it does not make one intelligent-design theory more reasonable than another. Listeners are essentially left to fill in the blanks for themselves, and some will undoubtedly do so by substituting their religious beliefs for scientific ideas.

Time and again, science has shown that methodological naturalism can push back ignorance, finding increasingly detailed and informative answers to mysteries that once seemed impenetrable: the nature of light, the causes of disease, how the brain works. Evolution is doing the same with the riddle of how the living world took shape. Creationism, by any name, adds nothing of intellectual value to the effort. —J.R.
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« Reply #111 on: 13 February 2018, 3:45:59 AM »


Natalie Wolchover
Senior Writer

January 22, 2014

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BiologyBiophysicsEvolutionOrigins Of LifePhysicsStatistical MechanicsStatistical PhysicsThermodynamics
Why does life exist?

Popular hypotheses credit a primordial soup, a bolt of lightning and a colossal stroke of luck. But if a provocative new theory is correct, luck may have little to do with it. Instead, according to the physicist proposing the idea, the origin and subsequent evolution of life follow from the fundamental laws of nature and “should be as unsurprising as rocks rolling downhill.”

From the standpoint of physics, there is one essential difference between living things and inanimate clumps of carbon atoms: The former tend to be much better at capturing energy from their environment and dissipating that energy as heat. Jeremy England, a 31-year-old assistant professor at the Massachusetts Institute of Technology, has derived a mathematical formula that he believes explains this capacity. The formula, based on established physics, indicates that when a group of atoms is driven by an external source of energy (like the sun or chemical fuel) and surrounded by a heat bath (like the ocean or atmosphere), it will often gradually restructure itself in order to dissipate increasingly more energy. This could mean that under certain conditions, matter inexorably acquires the key physical attribute associated with life.

Cells from the moss Plagiomnium affine with visible chloroplasts, organelles that conduct photosynthesis by capturing sunlight.
Cells from the moss Plagiomnium affine with visible chloroplasts, organelles that conduct photosynthesis by capturing sunlight.

Kristian Peters
“You start with a random clump of atoms, and if you shine light on it for long enough, it should not be so surprising that you get a plant,” England said.

England’s theory is meant to underlie, rather than replace, Darwin’s theory of evolution by natural selection, which provides a powerful description of life at the level of genes and populations. “I am certainly not saying that Darwinian ideas are wrong,” he explained. “On the contrary, I am just saying that from the perspective of the physics, you might call Darwinian evolution a special case of a more general phenomenon.”

His idea, detailed in a recent paper and further elaborated in a talk he is delivering at universities around the world, has sparked controversy among his colleagues, who see it as either tenuous or a potential breakthrough, or both.

England has taken “a very brave and very important step,” said Alexander Grosberg, a professor of physics at New York University who has followed England’s work since its early stages. The “big hope” is that he has identified the underlying physical principle driving the origin and evolution of life, Grosberg said.

“Jeremy is just about the brightest young scientist I ever came across,” said Attila Szabo, a biophysicist in the Laboratory of Chemical Physics at the National Institutes of Health who corresponded with England about his theory after meeting him at a conference. “I was struck by the originality of the ideas.”

Others, such as Eugene Shakhnovich, a professor of chemistry, chemical biology and biophysics at Harvard University, are not convinced. “Jeremy’s ideas are interesting and potentially promising, but at this point are extremely speculative, especially as applied to life phenomena,” Shakhnovich said.

England’s theoretical results are generally considered valid. It is his interpretation — that his formula represents the driving force behind a class of phenomena in nature that includes life — that remains unproven. But already, there are ideas about how to test that interpretation in the lab.

“He’s trying something radically different,” said Mara Prentiss, a professor of physics at Harvard who is contemplating such an experiment after learning about England’s work. “As an organizing lens, I think he has a fabulous idea. Right or wrong, it’s going to be very much worth the investigation.”

A computer simulation by Jeremy England and colleagues shows a system of particles confined inside a viscous fluid in which the turquoise particles are driven by an oscillating force. Over time (from top to bottom), the force triggers the formation of more bonds among the particles.
A computer simulation by Jeremy England and colleagues shows a system of particles confined inside a viscous fluid in which the turquoise particles are driven by an oscillating force. Over time (from top to bottom), the force triggers the formation of more bonds among the particles.

Courtesy of Jeremy England
At the heart of England’s idea is the second law of thermodynamics, also known as the law of increasing entropy or the “arrow of time.” Hot things cool down, gas diffuses through air, eggs scramble but never spontaneously unscramble; in short, energy tends to disperse or spread out as time progresses. Entropy is a measure of this tendency, quantifying how dispersed the energy is among the particles in a system, and how diffuse those particles are throughout space. It increases as a simple matter of probability: There are more ways for energy to be spread out than for it to be concentrated. Thus, as particles in a system move around and interact, they will, through sheer chance, tend to adopt configurations in which the energy is spread out. Eventually, the system arrives at a state of maximum entropy called “thermodynamic equilibrium,” in which energy is uniformly distributed. A cup of coffee and the room it sits in become the same temperature, for example. As long as the cup and the room are left alone, this process is irreversible. The coffee never spontaneously heats up again because the odds are overwhelmingly stacked against so much of the room’s energy randomly concentrating in its atoms.

Although entropy must increase over time in an isolated or “closed” system, an “open” system can keep its entropy low — that is, divide energy unevenly among its atoms — by greatly increasing the entropy of its surroundings. In his influential 1944 monograph “What Is Life?” the eminent quantum physicist Erwin Schrödinger argued that this is what living things must do. A plant, for example, absorbs extremely energetic sunlight, uses it to build sugars, and ejects infrared light, a much less concentrated form of energy. The overall entropy of the universe increases during photosynthesis as the sunlight dissipates, even as the plant prevents itself from decaying by maintaining an orderly internal structure.

Life does not violate the second law of thermodynamics, but until recently, physicists were unable to use thermodynamics to explain why it should arise in the first place. In Schrödinger’s day, they could solve the equations of thermodynamics only for closed systems in equilibrium. In the 1960s, the Belgian physicist Ilya Prigogine made progress on predicting the behavior of open systems weakly driven by external energy sources (for which he won the 1977 Nobel Prize in chemistry). But the behavior of systems that are far from equilibrium, which are connected to the outside environment and strongly driven by external sources of energy, could not be predicted.

This situation changed in the late 1990s, due primarily to the work of Chris Jarzynski, now at the University of Maryland, and Gavin Crooks, now at Lawrence Berkeley National Laboratory. Jarzynski and Crooks showed that the entropy produced by a thermodynamic process, such as the cooling of a cup of coffee, corresponds to a simple ratio: the probability that the atoms will undergo that process divided by their probability of undergoing the reverse process (that is, spontaneously interacting in such a way that the coffee warms up). As entropy production increases, so does this ratio: A system’s behavior becomes more and more “irreversible.” The simple yet rigorous formula could in principle be applied to any thermodynamic process, no matter how fast or far from equilibrium. “Our understanding of far-from-equilibrium statistical mechanics greatly improved,” Grosberg said. England, who is trained in both biochemistry and physics, started his own lab at MIT two years ago and decided to apply the new knowledge of statistical physics to biology.


David Kaplan explains how the law of increasing entropy could drive random bits of matter into the stable, orderly structures of life.
David Kaplan explains how the law of increasing entropy could drive random bits of matter into the stable, orderly structures of life.

Filming by Tom Hurwitz and Richard Fleming. Editing and motion graphics by Tom McNamara. Music by Podington Bear.
Using Jarzynski and Crooks’ formulation, he derived a generalization of the second law of thermodynamics that holds for systems of particles with certain characteristics: The systems are strongly driven by an external energy source such as an electromagnetic wave, and they can dump heat into a surrounding bath. This class of systems includes all living things. England then determined how such systems tend to evolve over time as they increase their irreversibility. “We can show very simply from the formula that the more likely evolutionary outcomes are going to be the ones that absorbed and dissipated more energy from the environment’s external drives on the way to getting there,” he said. The finding makes intuitive sense: Particles tend to dissipate more energy when they resonate with a driving force, or move in the direction it is pushing them, and they are more likely to move in that direction than any other at any given moment.

“This means clumps of atoms surrounded by a bath at some temperature, like the atmosphere or the ocean, should tend over time to arrange themselves to resonate better and better with the sources of mechanical, electromagnetic or chemical work in their environments,” England explained.

Self-Replicating Sphere Clusters: According to new research at Harvard, coating the surfaces of microspheres can cause them to spontaneously assemble into a chosen structure, such as a polytetrahedron (red), which then triggers nearby spheres into forming an identical structure.
Self-Replicating Sphere Clusters: According to new research at Harvard, coating the surfaces of microspheres can cause them to spontaneously assemble into a chosen structure, such as a polytetrahedron (red), which then triggers nearby spheres into forming an identical structure.

Courtesy of Michael Brenner/Proceedings of the National Academy of Sciences
Self-replication (or reproduction, in biological terms), the process that drives the evolution of life on Earth, is one such mechanism by which a system might dissipate an increasing amount of energy over time. As England put it, “A great way of dissipating more is to make more copies of yourself.” In a September paper in the Journal of Chemical Physics, he reported the theoretical minimum amount of dissipation that can occur during the self-replication of RNA molecules and bacterial cells, and showed that it is very close to the actual amounts these systems dissipate when replicating. He also showed that RNA, the nucleic acid that many scientists believe served as the precursor to DNA-based life, is a particularly cheap building material. Once RNA arose, he argues, its “Darwinian takeover” was perhaps not surprising.

The chemistry of the primordial soup, random mutations, geography, catastrophic events and countless other factors have contributed to the fine details of Earth’s diverse flora and fauna. But according to England’s theory, the underlying principle driving the whole process is dissipation-driven adaptation of matter.

This principle would apply to inanimate matter as well. “It is very tempting to speculate about what phenomena in nature we can now fit under this big tent of dissipation-driven adaptive organization,” England said. “Many examples could just be right under our nose, but because we haven’t been looking for them we haven’t noticed them.”

Scientists have already observed self-replication in nonliving systems. According to new research led by Philip Marcus of the University of California, Berkeley, and reported in Physical Review Letters in August, vortices in turbulent fluids spontaneously replicate themselves by drawing energy from shear in the surrounding fluid. And in a paper appearing online this week in Proceedings of the National Academy of Sciences, Michael Brenner, a professor of applied mathematics and physics at Harvard, and his collaborators present theoretical models and simulations of microstructures that self-replicate. These clusters of specially coated microspheres dissipate energy by roping nearby spheres into forming identical clusters. “This connects very much to what Jeremy is saying,” Brenner said.

Besides self-replication, greater structural organization is another means by which strongly driven systems ramp up their ability to dissipate energy. A plant, for example, is much better at capturing and routing solar energy through itself than an unstructured heap of carbon atoms. Thus, England argues that under certain conditions, matter will spontaneously self-organize. This tendency could account for the internal order of living things and of many inanimate structures as well. “Snowflakes, sand dunes and turbulent vortices all have in common that they are strikingly patterned structures that emerge in many-particle systems driven by some dissipative process,” he said. Condensation, wind and viscous drag are the relevant processes in these particular cases.

“He is making me think that the distinction between living and nonliving matter is not sharp,” said Carl Franck, a biological physicist at Cornell University, in an email. “I’m particularly impressed by this notion when one considers systems as small as chemical circuits involving a few biomolecules.”

If a new theory is correct, the same physics it identifies as responsible for the origin of living things could explain the formation of many other patterned structures in nature. Snowflakes, sand dunes and self-replicating vortices in the protoplanetary disk may all be examples of dissipation-driven adaptation.
If a new theory is correct, the same physics it identifies as responsible for the origin of living things could explain the formation of many other patterned structures in nature. Snowflakes, sand dunes and self-replicating vortices in the protoplanetary disk may all be examples of dissipation-driven adaptation.

Wilson Bentley
England’s bold idea will likely face close scrutiny in the coming years. He is currently running computer simulations to test his theory that systems of particles adapt their structures to become better at dissipating energy. The next step will be to run experiments on living systems.

Prentiss, who runs an experimental biophysics lab at Harvard, says England’s theory could be tested by comparing cells with different mutations and looking for a correlation between the amount of energy the cells dissipate and their replication rates. “One has to be careful because any mutation might do many things,” she said. “But if one kept doing many of these experiments on different systems and if [dissipation and replication success] are indeed correlated, that would suggest this is the correct organizing principle.”

Brenner said he hopes to connect England’s theory to his own microsphere constructions and determine whether the theory correctly predicts which self-replication and self-assembly processes can occur — “a fundamental question in science,” he said.

Having an overarching principle of life and evolution would give researchers a broader perspective on the emergence of structure and function in living things, many of the researchers said. “Natural selection doesn’t explain certain characteristics,” said Ard Louis, a biophysicist at Oxford University, in an email. These characteristics include a heritable change to gene expression called methylation, increases in complexity in the absence of natural selection, and certain molecular changes Louis has recently studied.

If England’s approach stands up to more testing, it could further liberate biologists from seeking a Darwinian explanation for every adaptation and allow them to think more generally in terms of dissipation-driven organization. They might find, for example, that “the reason that an organism shows characteristic X rather than Y may not be because X is more fit than Y, but because physical constraints make it easier for X to evolve than for Y to evolve,” Louis said.

“People often get stuck in thinking about individual problems,” Prentiss said. Whether or not England’s ideas turn out to be exactly right, she said, “thinking more broadly is where many scientific breakthroughs are made.”
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« Reply #112 on: 02 April 2018, 0:06:03 AM »

A Visit to the Institute for Creation Research

On January 9, 1998, a group of about 25 skeptics visited the "Museum of Creation and Earth History" run by the Institute for Creation Research in Santee, California. This tour was a part of a workshop entitled "Creation/Evolution" which was sponsored by the Committee for the Scientific Investigation of Claims of the Paranormal. The ICR staff was made aware that our group would be visiting the museum, and they suggested an introductory lecture followed by a tour of the museum.

The lecture was given by geologist Dr Steve Austin, who showed us a video which he said is also shown at the Mt St Helens visitor center. The Mt St Helens eruption was described in accurate detail, and there was a great emphasis on the velocities of the mudflows and the amounts of material that were removed and deposited elsewhere.

It was Austin's intention to use the Mt St Helens eruption to convince us that catastrophes can cause rapid, large-scale changes on the earth's surface. Austin said that he had once been an evolutionist, but that his observations of the Mt St Helens eruption had converted him to catastrophism and creationism. He set up a "straw man", implying that his "catastrophist" view of geology was something new and revolutionary in the geologic world and that "uniformitarian" (that is, mainstream) geologists ignore the role of volcanoes and other catastrophic events in the shaping the earth. One of our group leaders, PhD paleontologist Jere Lipps, took Austin to task for having such a simplistic view.

Austin continued his presentation by showing us some of his slides of the Mt St Helens area. One slide was simply described as showing "strata 25 feet high deposited by Mt St Helens". He referred to this stratified volcanic ash oniy as '"sedimentary rock" and observed that it took only a few hours to be deposited in layers. What was implied here, of course, was that large-scale sedimentary strata, such as limestones and sandstones found in many parts of the world, could be deposited in a similar, rapid manner. I asked Austin whether he had any evidence that any of the more typical sedimentary rock—limestone, sandstone, or shale—had ever been deposited rapidly, but he provided no such example. Our group's level of geologic expertise was above average, but I wonder how many less-skeptical people have left such presentations thinking that all sedimentary rocks show evidence of rapid deposition.

Young-earth creationists would be interested in a mechanism that allowed for the rapid formation of coal (since coal would have time to form in a young earth only if such a mechanism existed). Austin pointed out the post-eruption burial of trees in a nearly vertical, root-down position at the bottom of Spirit Lake (apparently there are some trees in that position) and said that he was sure that coal was forming at Spirit Lake now.

He then referred to the petrified forests found in Yellowstone Park and described them as remnants of similar ancient catastrophes (to be fair, he never came right out and said "'Flood of Noah""). The generally-accepted view of the petrified forests of Yellowstone — that the trees represent 27 forests, buriedsequentially by many volcanic episodes — was not mentioned. Austin also failed to mention why, if these forests in Yellowstone were such good models for catastrophic burial and coal formation, they do not contain any coal deposits. Erling Dorf, in his comprehensive article on the petrified Yellowstone forests, reported the presence of conglomerates from stream deposits, breccias from mudflows or landslides, volcanic tuff from the numerous volcanic events, and lava beds — but no coal!

Though Austin described himself as "an age-dating agnostic", he was eager to share with us the fact that he alone had radiometrically dated the Mt St Helens lava dome. Using potassium/argon dating, he determined a lava dome age of 350 000 years. His unstated conclusion was that radiometric methods are unreliable and give all sorts of bogus dates. There are, however, several other explanations of his results.

First, Austin sent young, low-potassium rocks to Geochron Laboratories. Such samples are very low in radiogenic argon, which is the isotope responsible for the radioactive decay that is the basis of the dating techniques. Although Geochron specifically stated that it did not want to deal with young, low-potassium samples, Austin sent them anyway and specifically stated in his paper that he did not reveal the origin of the samples. This "omission" can result in potentially large ranges of error in the results and also opens his research to ethical questions.

Second,Austin may have dated some of the solid material that came up with the lava rather than the lava itself. Austin had mentioned that the lava contained xenoliths—pieces of solid rock that came up with the lava. Although Austin stated that he was careful to remove the xenoliths, we have no assurances that he succeeded; and he apparently made no effort to date the xenoliths separately. Although Austin's date was published in a "peer-reviewed" journal (Creation Ex Nihilo Technical Journal), this journal is "peer-reviewed" only in the sense that the journal was published by other creationists. The peer-review process of a mainstream geology journal would have demanded that he explain his unusual results more completely Therefore, contamination by rock that is 350,000 years old or older remains a possibility.

Third, some of Austin's previous forays into the radiometric dating of rocks demonstrate that he is not an expert in this field. Austin is the head of the ICR's "Grand Canyon Dating Project". As such, he is committed to casting doubt on the radiometric ages of the lavas in the Grand Canyon. In a 1992 publication, ICR Impact#224: "Excessively Old 'Ages'" for Grand Canyon Lava Flows", Austin asserted that he found Cenozoic (relatively recent) lavas that gave radiometric (Sr/Rb) ages of 1.34 billion years.

These assertions are completely debunked in Chris Stassen's "Criticism of the ICR's Grand Canyon Dating Project" at the Talk.Origins Archive (http://www.talkorigins.org/faqs/icrscience.html#sec2, last accessed 1-13-98). Stassen points out that Austin's Grand Canyon lavas came from different flows, and the "ages" of the flows may actually represent a minimum age for the mantle that served as source material for the flows. Despite the obvious problems with Austin's methods, Impact #224 is alive, well, and available at the ICR museum!

Austin's last point about Mt St Helens was that the rapid erosion of volcanic ash in the Mt St Helens area (which he calls the "Little Grand Canyon") was a good model for catastrophic erosion over much larger areas. He proposed the existence of large pluvial lakes above the current Grand Canyon. According to this scenario the Canyon itself was cut when the lakes drained catastrophically. Again, this presumes that recently-deposited volcanic ash has properties similar to those of lithified limestone, sandstone, and shale — something most mainstream geologists do not accept.

As a young-earth creationist, Austin presumably believes that the sedimentary strata of the Grand Canyon were laid down rapidly and catastrophically during The Great Flood. I was eager to hear Austin's response to what I would consider a general problem for catastrophists, whether we are talking about catastrophic erosion of sedimentary strata or floods depositing these strata. Many of the sedimentary strata in and around the Grand Canyon contain the tracks of animals. The red Kayenta formation, exposed nearer to Glen Canyon Dam, contains the tracks of dinosaurs. I have seen these tracks personally and told Austin so. I asked Austin to comment on the fact that these tracks exist and are difficult to square with a catastrophic formation of the layers of the Grand Canyon. It is inconsistent to have all life on earth obliterated by a flood and then have animal tracks in the layers deposited by the flood. Austin stated that these certainly were animal tracks, laid down by animals walking through mud or sand, but he never satisfactorily explained how animals could happily meander through an area during or so soon after a global catastrophe.

At the end of the presentation Austin was confronted by another member of our group, who asked, "Whatever happened to Stuart Nevins? Does he publish anymore?" Those of you familiar with ICR literature may recognize the name from tracts published in the late 70's. Austin admitted that he had published under that pen name. So much for his recent, Mt St Helens-induced conversion to creationism!

Our group of skeptics was beginning to realize what passed for reality at the ICR, and we had not even set foot in the museum... yet.

[The author thanks Chris Stassen, Andrew MacRae, and Steve Austin for their helpful critiques via email and telephone.]
 

References

Austin S. Excess Argon within mineral concentrates from the new dacite lava dome at Mt St Helens Volcano.Creation Ex Nihilo Technical Journal 1997 http://www.icr.org/research/Sa/sa-r01.htm. Accessed 3-07-98.

Dorf E. The petrified forests of Yellowstone Park. Scientific American 1964 April; 79-85.

About the Author(s):
Dr Karen Bartelt
Eureka College
300 East College Avenue
Eureka IL 61530
Email: [email protected]
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« Reply #113 on: 03 April 2018, 15:21:29 PM »

http://www.dailymail.co.uk/sciencetech/article-5572125/Dinosaur-footprints-Isle-Skye.html
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« Reply #114 on: 06 April 2018, 4:35:36 AM »

Twenty-One Reasons Noah’s Worldwide Flood Never Happened
Email
Feature
Dr. Lorence G. Collins
Skeptical Inquirer Volume 42.2, March / April 2018
Twenty-One Reasons Noah’s Worldwide Flood Never Happened

Young-Earth creationists claim that the Paleozoic sedimentary rocks in the Grand Canyon and the Mesozoic sedimentary rocks of the Grand Staircase north of the canyon, in which Zion and Bryce Canyon National Parks occur, were deposited during Noah’s worldwide flood about 4,500 years ago (Hill 2002; Hill and Moshier 2009). I realize that readers of Skeptical Inquirer accept modern scientific views on this subject, but this examination of the creationist claims might be useful when communicating with others less imbued with scientific thinking.

There are at least twenty-one scientific reasons a worldwide flood recounted in the Bible cannot have happened.

The stair-stepped appearance of erosion of sedimentary rocks in the Grand Canyon with sandstones and limestones forming cliffs and shales forming gentle slopes cannot happen if all these rocks were deposited in less than one year. If the Grand Canyon had been carved soon after these rocks were deposited by a worldwide flood, they would not have had time to harden into solid rock and would have been saturated with water. Therefore, the sandstones and limestones would have slumped during the carving of the canyon and would not have formed cliffs (Hill et al. 2016).
Salt and gypsum deposits, more than 200 feet thick, occur in the Paradox Formation in Utah just 200 miles north of the Grand Canyon, and these deposits are the same age as the Supai rocks in the Grand Canyon that were supposedly also deposited by Noah’s flood. Similar salt deposits, up to 3,000 feet thick, exist in various places on all continents and in layers of all geologic ages, and these deposits can only be produced by evaporation of sea water. Such evaporation could not have happened in repeated intervals in the midst of the forty days and forty nights of raining and during the supposed continuous deposition of sedimentary rocks by a worldwide flood and in which the only drying and evaporation is said to have occurred at the end of the flood (Collins 2006; 2009; 2012; Hill et al. 2016).
Sand dunes with giant cross bedding occur in the Mesozoic rocks in Zion National Park and are further evidence that desert conditions occurred at the time of the supposed flood (Senter 2011; Collins 2017).
Fossilized mud cracks occur in the Cambrian Tapeats Formation on top of the Precambrian Vishnu schist at the bottom of the canyon and indicate that drying conditions existed during the alleged worldwide Noah’s flood, and these drying conditions occurred at the very beginning of this supposed flood. Although mud cracks can also form in mud under water by compression that squeezes out water from the mud, such compression is not likely to occur during a flood. Moreover, fossilized mud cracks are found in other formations that were supposedly deposited during Noah’s flood, and these mud cracks occur in red shales that coexist with salt and gypsum layers. Therefore, these mud cracks were likely formed in deltaic mud flats that were exposed to the atmosphere where their iron-bearing minerals reacted with oxygen in the air to form red hematite (Collins 2006; Senter 2011; Hill et al. 2016).
Raindrop prints occur in many places around the world, which could not have been formed or preserved if the muds (now in shales) containing these prints were deposited under water during Noah’s flood (Senter 2011; Hill et al. 2016).
Nests of dinosaur eggs are found in several places around the world, and it is illogical that dinosaurs could have had enough time to create these nests and lay their eggs while they were fleeing from rising waters to reach higher ground (Senter 2011; Hill et al. 2016).

The White Cliffs of Dover on the eastern coast of England consist of chalk layers, up to 350 feet thick, that are composed of fossilized coccoliths (a kind of algae), and these layers are the same age as the sedimentary rocks that overlie giant cross-bedded sandstones in Zion National Park. Therefore, they were supposedly also deposited by Noah’s flood. But coccoliths are very tiny and have chloroplasts that require sunlight and must float close to the ocean surface to get energy from the sun. Because of this, all of them could not have been living at the same time to depths of 350 feet in the one year in which the flood is said to have occurred because that many organisms in the water at the same time would have blocked out the sun from organisms below the near-surface (Collins 2015a).
Up to 4,590-foot thicknesses of radiolarians occur on the Pacific Ocean floor. Radiolarians are tiny marine organisms with silica skeletons; they contain chloroplasts and must float near the ocean surface to obtain sunlight. The rate at which dead radiolarians settle to the bottom of the ocean is too slow for that thickness and number of radiolarians to accumulate in the 4,500 years since Noah’s flood. Although radiolarians are not found in the sedimentary rocks of the Grand Canyon, fossilized radiolarians are common in sedimentary layers in other parts of the world of the same geologic age, and each of these layers contains distinctly different radiolarian species that are among more than 4,000 different species that have been identified. Chaotic rushing waters of a tsunami in Noah’s flood would have been unable to sort out these different species in different geologic ages from those living early in the flood to those created late in the flood (Collins 2015a).
None of the sedimentary rocks in the Grand Canyon contains fossilized pollen grains that are produced by grasses, pines, and flowering trees and plants, whereas these same rocks in the canyon contain only spores of algae, ferns, moss, and fungi. A worldwide flood would be expected to mix these tiny structures if all were alive at the same time of Noah’s flood, and this mixing did not occur. How can a rush of water in a tsunami sort out and separate such tiny reproductive structures from each other? (Hill et al. 2016).
The Redwall limestone in the Grand Canyon contains billions and billions of jumbled sea lily (crinoid) fossils in multiple layers, and such marine animals would have had to grow on stalks on the ocean floor and cover the whole Earth at space intervals of one foot apart if all were alive at the same time during Noah’s flood. That distribution and abundance is extremely unlikely in less than one year’s time. Moreover, there would have been the need for already available, precipitated, calcium carbonate crystals somewhere to be carried into the Grand Canyon area to be deposited as limestone to host these fossils. This seems highly unlikely because the source of the calcium requires long periods (tens of thousands of years) of chemical weathering of calcium-bearing rocks, such as basalt lava flows, to produce such a large volume of limestone that extends, not only in the Grand Canyon, but also in the Redwall limestone across most of western and central United States in buried sedimentary layers (Collins 2015a; Hill et al. 2016).
If all limestones were deposited by Noah’s flood during a giant tsunami, then all limestone layers should show evidence of fossils being jumbled by rushing water. This is not the case. The presence of Silurian limestone layers that are older than the Redwall limestone occur with consistent sequences at constant thicknesses over hundreds of square miles in Illinois, Iowa, and Wisconsin, and they lack any fossils in a jumbled array. These consistent thicknesses indicate that these limestone layers could not have been deposited by a tsunami, and these layers could only have been formed in quiet water by slow chemical precipitation of the calcium carbonate during tens of thousands of years. Thus, the limestones around the world, alleged to be deposited by Noah’s flood, were not deposited by a rush of flood water in a tsunami in less than one year. Many other examples occur in sedimentary rocks around the world where fossils of communities of many different marine animals are totally undisturbed (Senter 2011; Collins 2015a; 2017).
Abundant fusain (charcoal) is found in several different sedimentary rocks around the world that were supposedly deposited by Noah’s flood, which is good evidence that a worldwide flood never happened. Fires that burn forests are not likely to occur in the midst of forty days and nights of rain (Senter 2011).
River terraces exist on the sides of Colorado River canyon walls that give ages of deposition at the top of 350,000 years and at the bottom of 38,000 years, and these ages were determined by two entirely different methods and are much beyond the 4,500 years that young-Earth creationists claim is the age of the sedimentary rocks deposited during Noah’s flood (Collins 2015b; 2017).
Scientific observations and measurements show that the canyon of the Colorado River was eroded by rates of 80 to 458 meters per million years at different places along the canyon (Collins 2015b; 2017).
The coarsely crystalline Zoraster granite occurs in the Vishnu schist in the bottom of the Grand Canyon. Experimental work shows that coarse crystals in granite are formed only at depths of five miles or more in the Earth’s crust and that at these depths, the rate of cooling of rock melts (magma) at temperatures of more than 800 degrees C require at least 5 million years before temperatures are low enough that crystals can start to form and slowly increase in size. Therefore, the age of the Earth must be more than 6,000 years and much older than when Noah’s flood supposedly occurred (Collins 2017).
The rate of erosion of the Zoraster granite in the floor of Colorado River in Grand Canyon, as measured by how fast the erosion occurs on a yearly basis from year to year, is about a thousandth of an inch per year. This means that the carving of the Grand Canyon took millions of years—not less than a year in a sudden rush of water draining from three lakes at the end of Noah’s flood (Collins 2017).
The average thickness of sedimentary rocks around the world in the continents that were supposedly deposited by Noah’s flood is about 1,800 meters (5,905 feet) (Nelson 2012). If just 1 percent of this thickness represents fossil remains of marine animals that were alive at the same time during Noah’s flood, then the whole world would have been covered with 590 feet of living marine animals, such as clams, snails, corals, trilobites, and sponges. That many animals living at the same time during that single year would have been impossible. The value of 1 percent is not unreasonable when some limestone layers are composed of nearly 100 percent fossils. Even if 0.1 percent of the sedimentary rock thickness contained all marine animals that were alive at the same time in the year of Noah’s flood, that means that the whole world would have been covered with fifty-nine feet of animals, and that still is too many animals. The impossible numbers of fossils of coccoliths (Reason 7), radiolarians (Reason Cool, and sea lilies (Reason 10), are illustrative of this fact. Moreover, if only one out of 10,000 animals living on the land (amphibians, reptiles, birds, and mammals) are preserved as fossils in the sedimentary rocks deposited by Noah’s flood, then Noah would have had no space in which he, his family, and cattle could have existed with all these creatures living at the same time, particularly if tens of thousands of huge dinosaurs were alive when Noah lived prior to the flood.
An experiment done by Charles Munroe III shows that the submergence of an olive tree under water for more than three months kills the tree. On that basis, when a dove brought an olive twig with fresh leaves to Noah on the ark (Genesis 8:11), the whole world could not have been submerged under water during the flood. Otherwise, all olive trees would have been killed in six months of their submergence under the flood waters. Therefore, the flood must have been local in southern Mesopotamia with some land (say, 100 feet above water) present on which olive trees must have been growing and from which an olive tree with such a twig with fresh leaves could have been obtained by the dove (Collins 2017).
Wave action at high tide from a powerful category 5 hurricane with sustained winds of more than 156 mph can move an offshore barrier sandbar as much as 50 to 100 feet inland toward the continent, but such a major storm never moves sand for distances of thousands of miles across the United States, as creationists claim for the Tapeats, Coconino, and other sandstone deposits in the Grand Canyon or the calcite grains and fossils in the Redwall limestone. Therefore, producing such deposits by such winds and waves in Noah’s Flood has no scientific support. Noah’s ark could not have survived such wind power and large waves. Moreover, moving water cannot carry such large, suspended sediment loads for that distance (Collins 2015a; 2017).
The claim that the erosion surface that underlies the Cambrian Tapeats sandstone on top of the Precambrian basement rocks, which forms a major unconformity at the bottom of the Grand Canyon, was caused by a tsunami makes no scientific sense. A tsunami-created wave is caused by either a) a large earthquake following a sudden fault movement that shifts the position of the ocean floor; or b) a giant explosion of a volcano in an oceanic region, such as the explosion of Krakatoa—but never by flood waters of a large wave washing across the continent for thousands of miles. No such huge earthquake or explosion of a volcano is mentioned in the Bible, so postulating a tsunami to cause widespread rapid erosion across the world and at the bottom of the Grand Canyon at the beginning of Noah’s Flood is without biblical or scientific support (Collins 2017).
If the sedimentary rocks in the Grand Canyon were all deposited by Noah’s worldwide flood, then these rocks should all be deposited in less than one year under water and show continuous deposition from one formation to the next up the canyon walls without disruption. But that is not the case. For example, the Redwall limestone formation has ancient karst topography with caves and sinkholes, indicating that this formation was once lifted out of the water so that percolating rain water dissolved out cavities and tunnels in the limestone; erosion channels of the Temple Butte Formation, as much as 100 feet deep, cut the top of the Muav limestone, and networks of channels of the Surprise Canyon Formation, up to a half mile wide and 400 feet deep, cut the top of the Redwall limestone, indicating that these rocks were exposed at the Earth’s surface to river erosion (Hill et al. 2016). These structural land surface features would take much more than one year to be formed.
A Reasonable Possibility
Thomas H. Huxley (1825–1895) said the following: “The great tragedy of science—the slaying of a beautiful hypothesis by an ugly fact.” Any one of the above twenty-one facts destroys the idea that Noah’s flood was a worldwide occurrence. Nevertheless, a local large flood in Mesopotamia in biblical times could have been possible (Collins 2009). Young-Earth creationists commonly point out that Jesus supported the existence of Noah’s flood (Luke 17:27; Matthew 24:38–39), but in the context of the time in which Jesus lived, the translation of the Hebrew word ertz would have been understood as “land” and not the whole world. In that sense, all the land that Noah could have normally seen would have been under water in that part of Mesopotamia and that would have been in effect his whole world. During large floods in Iraq (Mesopotamia), commonly abundant rain falling in the adjacent Zagros Mountains goes underground in solution tunnels in limestone beds and emerges as gushing water in springs in Iraq. These springs are likely the “fountains of the great deep” as described in Genesis 7:11 (Hill 2015).

References
Collins, L.G. 2006. Time to accumulate chloride ions in the world’s oceans. Creationism’s young Earth not supported. Reports of the National Center for Science Education 26(5): 16–24. Available online at http://www.csun.edu/~vcgeo005/collins.pdf.
———. 2009. Yes, Noah’s flood may have happened but not over the whole earth. Reports of the National Center for Science Education 29(5): 38–41. Available online at http://www.csun.edu/~vcgeo005/Collins2.pdf.
———. 2012. More geologic reasons Noah’s flood never happened. Reports of the National Center for Science Education 32(6): 1–11. Available online at http://www.csun.edu/~vcgeo005/Collins3.pdf.
———. 2015a. Can flood geology and catastrophic plate tectonics explain sedimentary rocks? Available online at http://www.csun.edu/~vcgeo005/Collins5.pdf.
———. 2015b. When was Grand Canyon carved—millions of years ago or thousands of years ago? How do we know? Reports of the National Center for Science Education 35(4): 2.1–2.8. Available online at http://www.csun.edu/~vcgeo005/GrandCanyon.pdf.
———. 2017. When was the Grand Canyon formed? 4,360 years ago during Noah’s flood? Or during millions of years by natural geologic processes. Power point presentation available online at http://www.csun.edu/~vcgeo005/PwrPt1.pdf and http://www.csun.edu/~vcgeo005/PwrPt2.pdf.
Hill, C. 2002. The Noachian flood: Universal or local? Perspectives in Science and Christian Faith 54(3): 170–183. Available online at http://www.csun.edu/~vcgeo005/Carol%201.pdf.
———. 2015. A world view Approach to Science and Scripture (unpublished book).
Hill, C., G. Davidson, T. Helble, et al. (editors). 2016. The Grand Canyon—Monument to an Ancient Earth – Can Noah’s Flood Explain the Grand Canyon? Kregel Publications.
Hill, C., and S. Moshier. 2009. Flood geology and the Grand Canyon: A critique. Perspectives in Science and Christian Faith 61(2): 99–115. Available online at http://www.csun.edu/~vcgeo005/Carol%202.pdf.
Nelson, S.A. 2012. Geology 212, petrology. Occurrence, Mineralogy, Texture, and Structures of Sedimentary Rocks. Available online at http://www.tulane.edu/~sanelson/eens212/sedrxintro.htm.
Senter, P. 2011. The defeat of flood geology by flood geology. The ironic demonstration that there is no trace of the Genesis flood in the geologic record. Reports of the National Center for Science Education 31(3): 1–14. Available online at http://www.csun.edu/~vcgeo005/Flood%20geology.pdf.
Dr. Lorence G. Collins
Lorence G. Collins is a retired professor of geology from California State University Northridge. He has thirty-six articles on the website Opposition to Creationism (http://www.csun.edu/~vcgeo005/creation.html) that describe various views of young-Earth creationists and their scientific errors in interpretations. Among these are three articles that discuss a bogus fossilized Noah’s ark in eastern Turkey.
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« Reply #115 on: 14 April 2018, 17:35:08 PM »


All species possess vestigial features, which range in type from anatomical to physiological to behavioral. More than 100 vestigial anomalies occur in humans. The following list explores 7 of them.

* Palmar Grasp Reflex

inherited reflexPalmar grasp reflex in The palmar grasp reflex is a characteristic behavior of human infants, developing as early as 16 weeks gestational age, when the fetus begins to grasp the umbilical cord in the mother’s womb. Early research found that human newborns, relying on their grasp reflex, could hold their own weight for at least 10 seconds when hanging by their hands from a horizontal rod. By comparison, monkey infants, which possess a similar involuntary grasping behavior, were able to hang from one hand for more than half an hour. The reflex is essential for monkey infants, enabling them to cling to the mother’s body fur. But humans, who evolved out of an arboreal existence and lost the covering of fur over the body, presumably no longer require that powerful grasp. Human infants typically begin to lose the reflex around three months of age. Despite its diminished strength and loss in early infancy, some researchers think that the grasp reflex may retain important functions in humans.

* Tails
In the sixth week of gestation, the human embryo possesses a tail, complete with several vertebrae. In the next couple weeks of development, however, the tail disappears, and over time the vertebrae fuse to form the coccyx, or tailbone, in the adult. Humans and their ape relatives are distinguished from other groups of primates in part by their taillessness, though it is unclear why apes lost their tails. On rare occasion, a human infant is born with a vestigial tail. In modern medical literature, such tails lack vertebrae and typically are harmless, though some are associated with spina bifida (failure of the vertebrae to completely enclose the spinal cord). Tails in human infants typically are removed through surgery without complication.
* Wisdom Teeth


As the human species migrated out of Africa, it came to populate a variety of habitats, and eventually, human civilizations developed. Coincident with those events was a shift in the human diet toward the consumption of soft and processed foods, which gradually eliminated the need for large, powerful jaws. With a reduction in human jaw size, molars—particularly the third molars, or wisdom teeth—became highly prone to impaction. Increasingly, wisdom teeth are congenitally absent. As a consequence, they are now considered a vestigial feature of the human body.

* Nictitating Membrane
The plica semilunaris is a fold of conjunctiva at the inner corner of the human eye. Its likeness to the nictitating membrane, or third eyelid, of other animals led to the idea that it might be the vestige of such a structure, which is still part of the eye in some primates, including gorillas. In the chimpanzee, however—one of the human species’ closest relatives—the plica semilunaris also appears to be vestigial. The function of the nictitating membrane in many animals is protective—for example, keeping the eye clean and moist or concealing the iris from predators. In some species, the membrane is sufficiently transparent so as to enable vision when underground or underwater. Though the reason for the loss of a nictitating membrane in humans in unclear, changes in habitat and eye physiology may have rendered the tissue unnecessary.
*
Auricular Muscles
The auricular, or extrinsic, muscles of the human ear include the anterior auricular muscle, the superior auricular muscle, and the posterior auricular muscle. Together, they control the pinna, or the visible part of the ear. In many mammals, ear movements produced by the auricular muscles play a role in sound localization and the expression of emotion, but in humans, the muscles are considered nonfunctional. Darwin proposed that humans effectively capture sounds by positioning the head to receive them, thereby compensating for the loss of or eliminating the need for the auricular muscles. Through repeated effort, however, humans can recover some ability to wiggle their ears.

* Palmaris Longus Muscle
Research has indicated that the palmaris longus, a thin strip of muscle running between the wrist and the elbow, is absent from both arms in about 10 percent of humans. The muscle presumably functioned in grip, with some speculation that it was of particular importance for hanging. In modern humans, however, the muscle’s absence has no impact on grip strength. Today, the palmaris longus is commonly harvested as a source of tissue for tendon grafting in reconstructive surgery.
*
Pyramidalis Muscle
The pyramidalis muscle is a paired, triangular-shaped muscle that, when present, is located in the lower abdomen between the muscle and muscle sheath of the rectus abdominis. The pyramidalis muscles vary in size and in number—with some people having two, one, or none. They may serve to contract the linea alba, an activity that is considered irrelevant to the function of the abdominal muscles. Researchers have estimated that one or both pyramidalis muscles are present in about 80 percent of the human population.


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« Reply #116 on: 13 June 2018, 23:11:50 PM »

Astounding discovery: There was life on Earth some 3.5 billion years ago in oxygen-devoid environment
Dec 28, 2017 Stefan Andrews
The latest research findings by scientists catch traces of life on our planet going back roughly 3.5 billion years. A newly published study affirms the claim by analyzing 11 microbial samples coming from five distinct organisms. Scientists have used new technological instruments to prove that the retrieved samples had, once, been living microorganisms. They have managed to link the morphology of the microbes to their chemical signatures, and have proceeded to assign each specimen to a biological identity.
Some of the now-extinct specimens have been identified as belonging to the kingdom of single-celled microbes and bacteria known as Archaea, while other samples are similar to microbial life that thrives today. Given the age of the microfossils, these living organisms existed on the Earth when it was nothing like what we know today and was even devoid of oxygen.
The findings were delivered by researchers at UCLA and the University of Wisconsin-Madison, and were published on December 18, 2017, in the scientific journal Proceedings of the National Academy of Sciences. The research and study activities were led by UCLA’s professor of paleobiology, J. William Schopf, as well as University of Wisconsin-Madison’s professor of geoscience, John W. Valley.
The scientists have dubbed the specimens microfossils since they obviously cannot be seen by the naked eye. As Schopf clarified, the nature of the life forms are “a primitive, but diverse group of organisms.” To make things all the more exciting, such organisms, Schopf says, could be widespread
Scientists say that already a few different types of microbes have been proven to be 3.5 billion years of age. Schopf says: “Life had to have begun substantially earlier–nobody knows how much earlier–and confirms it is not difficult for primitive life to form and to evolve into more advanced microorganisms.”
Some of the identified specimens are phototrophic bacteria, which would have made use of the sun to produce energy. In the case of the Archaea, they did produce methane, while another identified specimen, gammaproteobacteria, would have nurtured itself with the same gas. Furthermore, it is deemed that methane was a significant ingredient in the composition the early atmosphere of Earth.

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« Reply #117 on: 17 August 2018, 22:20:54 PM »

Study confirms truth behind 'Darwin's moth'
UNIVERSITY OF EXETER
CREDIT: OLIVIA WALTON

Scientists have revisited - and confirmed - one of the most famous textbook examples of evolution in action.

They showed that differences in the survival of pale and dark forms of the peppered moth (Biston betularia) are explained by how well camouflaged the moths are to birds in clean and polluted woodland.
"Industrial melanism" - the prevalence of darker varieties of animals in polluted areas - and the peppered moth provided a crucial early example supporting Darwin's theory of evolution by natural selection, and has been a battleground between evolutionary biologists and creationists for decades.
The common pale form of the moth is camouflaged against lichen growing on tree bark. During the Industrial Revolution - when pollution killed lichen and bark was darkened by soot - a darker-winged form emerged in the UK.
Later, clean air legislation reduced soot levels and allowed lichen to recover - causing a resurgence of pale peppered moths.
The example has been well supported by many studies, but nobody had ever tested how well camouflaged the moths were to the vision of their key predators - birds - and how their camouflage directly influenced survival.
Now scientists at the University of Exeter have shown that, to the vision of birds, pale moths are indeed more camouflaged against lichen-covered trees than dark moths - making pale moths less likely to be eaten by birds in unpolluted woodland and giving them an evolutionary advantage.
"This is one of the most iconic examples of evolution, used in biology textbooks around the world, yet fiercely attacked by creationists seeking to discredit evolution," said Professor Martin Stevens, of the Centre for Ecology and Conservation on the University of Exeter's Penryn Campus in Cornwall.
"Remarkably, no previous study has quantified the camouflage of peppered moths, or related this to survival against predators in controlled experiments.
"Using digital image analysis to simulate bird vision and field experiments in British woodland, we compared how easily birds can see pale and darker moths, and ultimately determine their predation risk.
"Our findings confirm the conventional story put forward by early evolutionary biologists - that changes in the frequency of dark and pale peppered moths were driven by changes in pollution and camouflage."
Most birds can perceive ultraviolet light - invisible to human eyes - and see a greater range of colours than humans, and the Exeter scientists analysed how well pale and dark moths matched lichen-covered and plain tree bark, as seen by birds.
To do this, they used museum specimens including some from the collections of Bernard Kettlewell, who conducted famous research on the evolution of the species in the 1950s.
The researchers also created artificial moths, baited them with food and observed predation rates in UK woodland, mostly in Cornwall.
"Through a bird's eyes, the pale peppered moths more closely match lichen-covered bark, whereas darker individuals more closely match plain bark," said first author Olivia Walton, who conducted the research as part of her master's degree at Exeter.
"Crucially, this translates into a strong survival advantage; the lighter moths are much less likely to be seen by wild birds when on lichen-covered backgrounds, in comparison to dark moths."
In the experiment using artificial moths, lighter models had a 21% higher chance of "surviving" (not being eaten by birds).

"We provide strong direct evidence that the frequency of the peppered moth forms stems from differences in camouflage and avian predation, providing key support for this iconic example of natural selection," Professor Stevens said.
The research was funded by the Biotechnology and Biological Sciences Research Council (BBSRC)
The paper, published in the journal Communications Biology, is entitled: "Avian vision models and field experiments determine the survival value of peppered moth camouflage."
The birds that most commonly eat peppered moths include sparrows, great tits, blue tits, robins and blackbirds.

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« Reply #118 on: 24 September 2018, 14:04:19 PM »

558m-year-old fossils identified as oldest known animal
Oval-shaped Dickinsonia lifeform existed at least 20m years before the ‘Cambrian explosion’ of animal life

Anthea Lacchia

Thu 20 Sep 2018 19.00 BST Last modified on Fri 21 Sep 2018 10.02 BST
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 Scientists reveal secrets of oldest known animal fossil – video
A fossilised lifeform that existed 558m years ago has been identified as the oldest known animal, according to new research.

The findings confirm that animals existed at least 20m years before the so-called Cambrian explosion of animal life, which took place about 540m years ago and saw the emergence of modern-looking animals such as snails, bivalves and arthropods.

The new fossils, of the genus Dickinsonia, are the remains of an oval-shaped lifeform and part of an ancient and enigmatic group of organisms called Ediacarans. These creatures are some of the earliest complex organisms on Earth, but their place within the evolutionary tree has long puzzled scientists. Suggestions as to what they were have ranged from lichens to failed evolutionary experiments to bacterial colonies.

Now, by identifying the remains of organic matter on newly discovered Ediacaran fossils as ancient cholesterol, the scientists have been able to confirm Dickinsonia was an animal, which makes it the oldest known animal.

“It is the exact type and composition of that fat that was the giveaway that Dickinsonia was in fact an animal,” said Jochen Brocks of the Australian National University, one of the authors on the study. He added that the study solves “a decades-old mystery that has been the holy grail of palaeontology”.

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