Is the theory of evolution settled?

Posted by  $  Dobrien 8 months, 2 weeks ago to Science
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  • Posted by  $  MikeMarotta 8 months, 1 week ago
    The story from Newstarget is garbage. It is junk science, mysticism or ignorance presented in the language of science.

    Journalism teaches that the last paragraph is called a "moral tag." For a high school newspaper, a news story about the basketball team ends, "So, let's all go to the game tonight!" That is a moral tag. This is also a moral tag: "This means that the possibility of intelligent design is still very much on the table, despite what Darwinian adherents would have you believe. (Related: Huge contradictions in “scientific” thinking revealed … Theory of evolution in no way explains origins of life.)"

    As Alan said about his original post about the Mitochondrial DNA study: "... people shouldn't rule things in or rule out, promote or condemn something, until there is concrete evidence." That was all, nothing more or less than an appeal to reality.

    On my own blog, I have articles questioning the Darwinian theory of evolution. The reason that religionists attack Darwin is that they live of by and for a Book and its Authority. So, they pick one target -Darwin, Einstein - and attack that person and their ideas (often misrepresented), in order to push their mystical arguments. As noted earlier and as known to everyone, really, Darwin did not know about DNA. So, he did not have a mechanism to explain his observations. But the observations were valid: species exist; speciation occurs. The origin (and demise) of species is a natural process. It does not require a Mystical Entity to Create Life.

    Moreover, to strike to the core here, even if it were demonstrated by way of "ancient astronauts" that intelligent beings engineered some or all of Earth or life on it, that would not validate the Qu'ran or other holy books and their moral demands for self-sacrifice, based on a belief that "heaven" is only just above the clouds over which Nimrod could not shoot an arrow and that good people go there to play harps or chase virgin girls forever and ever...
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    • Posted by minorwork 8 months, 1 week ago
      Darwin actually presented 5 theories in the book, each of which has been tested and confirmed independently.

      1. Evolution as such: This is the simple idea that lineages of organisms change over time. This was not an idea that was original with Darwin. Lamarck and Darwin's own grandfather were evolutionists. However, Darwin proposed that these changes were more significant than previously proposed. This idea gained general acceptance almost immediately and has been universally accepted since. Even creationists, when presented with the overwhelming number of species that populate the earth propose "variation in kind" at rates that are exponentially greater than any ever proposed by an evolutionary biologist with the sole purpose of cramming them all on an ark.

      2. Gradualism: An idea original with Darwin. Darwin argued that differences between populations of organisms -- even radically different organisms -- accumulate by a series of innumerable small steps through intermediate forms. It should be clear that the typical creationist argument that a dog has never been observed to give birth to a cat, or a monkey to give birth to a human is a nonsense straw man. Evolutionary theory does not now, and never has claimed such drivel. Darwin did propose that intermediates between many living organisms were erased by extinction, and the evidence seems to indicate that he was correct. Creationists point to these gaps. When intermediate fossils are found, creationists point to two gaps or declare that the transitional is a "mosaic", without defining what this term means. On the other hand, creationists claim hyperevolution occurred after the flood in order to populate the earth from the few "kinds" for which there was room on the ark to the millions of species we observe today.

      3. Population speciation: Another idea that was original with Darwin. Individual organisms do not evolve and offspring are not different species from their parents. Evolution is a process that occurs in the heritable characteristics of a population over time. Even though Darwin knew nothing of genetics, this concept has become the very definition of evolution at the most fundamental level. Creationists snidely wonder if they should have a net handy in case their next child is born with wings and feel that this is a telling argument against evolution. But if such an event occurred, it would be an overwhelming blow to current theories of evolution. Any new structure is always a slight modification of a previously existing structure. Thus, after generations, a clawed forelimb becomes a clawed/feathered forelimb, which becomes a clawed wing, which becomes a wing. 5% of a wing is a tetrapod forelimb that is covered with epidermal extensions that retain heat.

      4. Common descent: This is the major crux for creationists and an idea original to Darwin. He was the first to argue that species had diverged from common ancestors and thus comprise a great tree of life. On the one hand, creationists deny this. Their scripture declares that there are immutable created "kinds," which implies that there is are limits to the change. On the other, they claim that 36 species of cats arose from a pair of the "cat kind" aboard the ark by "variation in kind." They also claim that 850 (or more) species of bats arose from a pair of the bat "kind" in only a couple of thousand years, radiating to nocternal insectivorous bats as well as diurnal fruit bats by simple variation of characteristics that the "original" bat "kind" possessed. So while creationists allow common descent of cats from the cat "kind", and dogs/wolves/coyotes/foxes/etc. from the "dog kind", they deny the descent of all carnivores from previous ancestors.

      5. Natural selection: Darwin's most brilliant and original hypothesis, independently arrived at by Wallace. Natural selection is the mechanism of change. It is based on a few simple observations and inferences:

      a. All organisms produce so many offspring than population size would increase exponentially if not constrained.
      b. Adult populations remain relatively constant.
      c. In any environment there exists a limited number of resources.
      d. As a result, all organisms must be engaged in a constant competition to acquire these limited resourses for themselves in order to survive.
      e. There exists in any population great variability such that no two individuals are exactly the same.
      f. Among the variable characteristics that all species have, some organisms have heritable characteristics that make them better able (or less able) than others to acquire the resources necessary for life.
      g. Those organisms that are better able to acquire the necessary resources are more likely to reach maturity and to pass those heritable characteristics on to their progeny, while those organisms that are at a disadvantage will tend to reproduce less (differential reproduction).
      h. As a result, populations change over time.

      Darwin and Wallace realized that this process operating within species would result in organisms that appeared designed for their environment.

      Although Darwin recognized the need for some sort of granular unit of heredity, he was unaware of the work of Mendel. This fact makes Darwin's ideas all the more remarkable.

      Gregor Mendel was a contemporary of Darwin who conducted extensive experiments in the breeding of plants from which he formulated his laws of inheritance. These laws formed the modern science of genetics.

      1. the law of segregation - genes normally occur in pairs in the ordinary body cells, but segregate in the formation of sex cells. When egg and sperm unite, forming a gene pair, the dominant gene masks the recessive gene. ('dominant' and 'recessive' are terms defined by Mendel)

      2. the law of independent assortment - the expression of a gene for any single characteristic is usually not influenced by the expression of another characteristic.

      The importance of Mendels work was not recognized for over 30 years. Even then, it was some years before it was recognized that Mendel's genes were the units of heredity that were predicted by Darwin. As a result of the synthesis of the theories of Mendel and Darwin there emerged in the 1930s what is known as the Synthetic Theory of evolution. The principal claims of this evolutionary synthesis became the foundations of modern evolutionary biology. Many of the following points have been extended, exemplified, clarified or modified. These points are recognized by the vast majority of evolutionary biologists as valid and have served as the basis for evolutionary research.

      Contributions from laboratory genetics

      1. The genotype (the set of genes carried by an individual) and the phenotype (the observed physical characteristics of an individual) are different. The phenotypic differences among individual organisms can be due partly to direct effects of the environment and partly to genetic differences.

      2. The genes an individual passes on to its offspring are not affected by environmental effects on the phenotype of that individual. In other words, acquired characteristics are not inherited. However, the environment may affect the expression of an organism's genes.

      3. Hereditary variations are based on particles called genes. Genes retain their identity as they pass from one generation to the next. They do not blend with other genes. This is true of genes that contribute to varying traits (size, pigmentation) as well as those that have a discrete effect (eye color). Variation in continuously varying traits is largely based on several discrete genes, sometimes many, each of which affects the trait slightly. This is called polygenetic inheritance.

      4. Genes sometimes change to alternative forms. These changes are called mutations and the alternative forms are called alleles. The rate of these changes is usually very slow. The phenotypic effects of such mutations can range from undetectable all the way to very great. Genetic variation that arises by mutation is amplified by recombination among alleles at different loci (gene locations on the chromosomes).

      5. The rate of mutation may be affected by environmental factors but such factors do not preferentially direct the production of mutations that would be favorable to any specific environment.
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      • Posted by Lucky 8 months, 1 week ago
        Your 5 theories post is a well written and expert outline.
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        • Posted by minorwork 8 months, 1 week ago
          It is and I wish I could remember where I found it and who wrote it.

          The "kinds" categorization was not noted. Hmmm, I wonder why not?

          I DO know who wrote the following, Paul Lutus, grade school dropout, a self-educated man whose design for the converters twixt the fuel cells and lights on all the Space Shuttles won out over formally trained electrical engineers, writer of the first world-class, world best seller word processor, Apple Writer.
          Religion functions to make its followers comfortable and self-assured in their innate superiority, but science (when properly understood) can only make one uncomfortable and doubtful about knowing anything for certain." ~ Paul Lutus in the Myths section of The Doubt Factory
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    • Posted by CircuitGuy 8 months, 1 week ago
      "The reason that religionists attack Darwin is that they live of by and for a Book and its Authority. "
      That's why they call us "Darwinist". They seem only to understand taking something as sacrosanct as the starting point.

      Darwin speculated about that Lamarckian evolution was one cause of evolution. I learned that Lamarcian evolution was completely wrong, that it was a leap forward conceptually, but now it's the stupid picture of giraffes having offspring with longer necks after a life of stretching to reach trees. Now maybe epigenetics is possibly turning out to be a form of that; or maybe not, I haven't had bio in 20 years. But whatever scientists are finding, anti-scientific people will always, "just tell me what's settled science. Don't keep changing your mind every time you find new evidence!"
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  • Posted by Lucky 8 months, 2 weeks ago
    Yes as a concept.
    Some details and mechanisms are still uncertain.
    The Newstarget article is pure fundamentalist religious muck.
    For a fair summary of the same research see-
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    • Posted by  $  Olduglycarl 8 months, 1 week ago
      Maybe it's me or maybe it's you but I see no fundamental religious much here, just because we can see and explain mass extinctions but can not explain mass arrivals doesn't equate to mysticism, even if it was referred to by those that were recounting history as it was brought forward by their ancestors.
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  • Posted by  $  Olduglycarl 8 months, 1 week ago
    We've investigated (you and I) cycles of many things including history itself. There does seem to be times in history of mass distinctions but what is really surprising is the sudden emergence of new species.
    I have looked into the books of Enoch, still not satisfied or onboard, it's interesting he describes in some detail the emergence of the animal and human kingdom.
    Again, not swayed but still curious.
    Wouldn't it be a kick in the butt if there was some validity to all that .

    As far as evolution within specific species, we do see several changes in Humans. 1 the 4 bloodtypes, brought about through epigenetic challenges. A, first, then a disappearance replaced by O then a reemergence; later, B (nomadic) and then 2500 years ago the emergence of AB. All validated through anthropological investigations...Not to mention, at least the observation of, the emergence of conscience, consciousness, self introspection and the emergence of unicameral thought or what we would now call the mind.
    The latter still a theory but with some reasoned observations whereas, the blood types and skin colors having a physical historical record to follow.
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    • Posted by  $  MikeMarotta 8 months, 1 week ago
      I agree generally with your facts. I do underscore the need to use the word "theory" correctly. You meant "conjecture." A theory is a consistent explanation of an obseved fact. That means that the theory is internally consistent (non-contradictory) and consistent reality, i.e., with other observed facts beyond the immediate question.
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    • Posted by minorwork 8 months, 1 week ago
      A sudden emergence of new species? I'd wondered about the new taxonomies of categorizing organisms.
      There are at least 7 species concepts used in modern biology. Which concept is being used depends on context. They are as follows:

      Biological Species Concept: A species is a group of interbreeding natural populations that are reproductively isolated from other such groups. This is the oldest definition, formulated in the late 1930s.

      Evolutionary Species Concept: A species is a single lineage of populations that maintains its identity from other such lineages.

      Phylogenetic Species Concept: A phylogenetic species is an irreducible cluster of organisms that is diagnosably distinct from other such clusters, and within which there is a parental pattern of ancestry and descent. Or, the smallest monophyletic group of common ancestry.

      Recognition Species Concept: A species is the most inclusive population of individual biparental organisms that share a common fertilization system.

      Cohesion Species Concept: A species is the most inclusive population of individuals having the potential for phenotypic cohesion through intrinsic cohesion mechanisms.

      Ecological Species Concept: A species is a lineage that occupies an adaptive zone minimally different from that of any other lineage in its range and which evolves separately from all lineages outside its range.

      Internodal Species Concept: Individual organisms are conspecific by virtue of their common membership in a part of the genealogical network between two permanent splitting events or between a permanent split and an extinction event.

      There you go. Those are the species concepts used in modern biology (thanks to Douglas Futuyma). The definitions are in chronological order according to the development of a specific view of biology. The last, the internodal Species Concept, was stated in 1993 with the development of cladistics.
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  • Posted by term2 8 months, 1 week ago
    As far as I am concerned, it is OBVIOUS that evolution has occurred. But it happens slowly. I live in Vegas, and all I have to do is look around to see the wide variations in the appearance of people. SOMETHING is responsible for the differences from nearly ape like head shapes to neanderthal head shapes, to lily white european complexions, to the distinctive look of asian faces.

    There is also a wide variation in intelligence from person to person. I have to say that I have read that chimpanzees are even "smarter" when young than human babies. I sometimes wonder whether it stays that way as some human babies grow up and become leftists.
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  • Posted by  $  allosaur 8 months, 1 week ago
    Me dino is a Christian who does not buck science.
    Keeping my examples simple, I know allosaurs and stegosaurs are only found in Jurassic Period rock layers and T -Rex and Triceratops are only found in Cretaceous Period rocks, both periods being two of three periods of the Mesozoic Era AKA The Dinosaur Age.
    Science says The Dinosaur Age ended 65 million years ago.
    All dinosaur fossils are found beneath a layer of iridium that only comes from outer space in such things as asteroids.
    Sometimes in great big asteroids .
    Mammal fossils are found both below and above that iridium layer, though.
    Hmm, me dino suddenly remembers being taught to duck and cover in elementary school during the late Fifties.
    Double hmm! It just hit my memory banks that birds survived too. Birds are even being called dinosaurs these days.
    Maybe some birds also lived in holes.
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  • Posted by LibertyBelle 8 months, 1 week ago
    If a meteor came about 63 million years ago and wiped out most species (including the dinosaurs), then it would kind of make sense that all the ones existing now would have started (over) at about the same time.
    Not that I care. I do not see that supernatural creation could be true in any case. Saying that nothing could come from nothing, and then that some Deity made the universe out of nothing is self-contradictory in the first place.
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  • Posted by philosophercat 8 months, 1 week ago
    Evolution is a fact as certain as gravity, the laws of thermodynamics, and the cell.
    Denial is tantamount to denying all of science which religion accept its anti rational premises of universal consciousness or God.
    Aristotle in the De Anima nailed it from simple observation but is validated 2400 years later. Today irrational minds cannot observe and cannot think.
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  • Posted by rtpetrick 8 months, 1 week ago
    So, if all animals and humans showed up on this planet at the same time, what conclusion can be formed? Creationism? Ancient Astronauts? Prometheus Engineers? Big Bang?
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  • Posted by scojohnson 8 months, 1 week ago
    I believe in science, and I also have my faith (and a near death experience once). I see the religious writings as a guidepost for enlightenment, not physical evolution.

    Something around the time of the Old Testament brought humans from cave dwelling for millions of years to what we are now within a tiny sliver of earth and human evolution. Why them? When for millions of years prior we were climbing trees.

    The religious argument fits well with the geological record if our intelligence and our soul was ‘begotten’ instead of evolving.
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  • Posted by Owlsrayne 8 months ago
    Once I read the byline I wasn't going to read a stupid article. Also, I recently had my ancestral DNA study done by Helix/Nat Geo because of the one from was not detailed enough. One thing surprised me was that I had a higher amount of Neaderthal DNA percentage than normal probably due to my ancestors came from northern Europe. The writer of the article should have his DNA done. Another interesting aspect of the testing result is virtually nothing from Africa. So, much for the African Eve in my case.
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  • Posted by  $  puzzlelady 8 months, 1 week ago
    This fine Objectivist forum has been invaded by Christian (by definition irrational) elements pushing the religious agenda. And by definition, they cannot be reasoned with or persuaded. Looks like the Gulch has been gutted. The few sane voices here are wasting their time. And I'm bored. I propose that we consider this forum to be on separate tracks, and we let the Christians do their thing (freedom of speech) without engaging them. They tend to stick like burrs on wool socks, so it's unlikely that they'll go away if we just ignore them. Their very mission is their in-your-face missionary work. Let the rest of us pursue our own intelligent conversations and not provide fuel for their zeal.
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  • Posted by Herb7734 8 months, 1 week ago
    The theory of evolution is still evolving. All evidence examined shows that evolution exists. But it is much more complex than the simple explanation of it that we are all familiar with'The apprent simplicity of the chemistry of life has confounded scientists for years, not to mention the most complex of all creatures, Man.The study of the DNA ladder and how it functions on an almost imperceptible level is still a mystery.. If the mysteries of the universe and of life were compared to a swimming pool you could say that up until last year we managed to put our speedos on and stick our toe in the shallow side.Learning about swimming won't begin for a while.
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  • Posted by Rex_Little 8 months, 1 week ago
    Natural selection obviously brings about changes in any given species, and in different groups of members of a species, over time. But I've never believed we have a handle on what causes the changes in one species' DNA that result in an entirely different species. We don't even know how the first DNA molecule came to be--do you know how complex those suckers are?

    I don't believe for a moment in an omnipotent Creator God, but there's got to be something going on beyond random chance.
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  • Posted by  $  jlogajan 8 months, 1 week ago
    It depends on who is asking. Religion explains everything. So whether that particular religion incorporates evolution or rejects it gives the answer. Naturalists, on the other hand, would just go by the available evidence. The increasing complexity in younger and younger rock strata suggests a very long consistent process. So called "bursts" of evolution which actually occurred over millions of years suggest the DNA at the point was already a toolkit from which a lot of new arrangements of already invented things (teeth, limbs, eyes, etc) could emerge quickly.
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  • Posted by  $  AJAshinoff 8 months, 2 weeks ago
    It is a theory which by defination means it is not settled.
    I wasn't pushing any type of answer in my post, religious or otherwise. I just take the position, as I said before here many times, that until you know definitively people shouldn't rule things in or rule out, promote or condemn something, until there is concrete evidence. Reality is pretty fascinating using that perspective..options are limitless, fully of possibilities.
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    • Posted by  $  MikeMarotta 8 months, 1 week ago
      You said "theory" but you used the word to mean "conjecture." The fact of evolution is not a conjecture. The mechanisms of evolution are observed facts, not all of which are consistently explained by a theory that is commonly accepted. But evolution is not a theory. It is a fact. Darwin's theory explains evolution. Other theories may explain it better, i.e., more consistently.
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      • Posted by minorwork 8 months, 1 week ago
        That a theory is open to being invalidated from another theory surpassing the details and measurements in forecasting based on its theory instead of Darwinism, is indeed the basis of science yet, to even rate being deemed a theory and not a hypothesis or conjecture or postulate, I know of no other than evolution that has the demonstrable success in helping us to wage war against PSED (Pain, Suffering, and Early Death) with even 25% of the success as understanding biology thru evolutionary principles. If there is a better proposal than evolution by which to understand biology, please sing out.
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    • Posted by salta 8 months, 1 week ago
      Scientific Theory does not mean "not settled", it means not yet disproved. They remain until disproved.
      Over time a well established theory might be referred to as a "Law" (eg. gravity) but there is no formal promotion involved. Newton's gravity theory is still a theory, which has been refined further by the Theory of Relativity, which, in turn, has been been confirmed by testing (so far), and so remains a theory.
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      • Posted by  $  AJAshinoff 8 months, 1 week ago
        Perhaps looking up the word will help
        ": a plausible or scientifically acceptable general principle or body of principles offered to explain phenomena"

        Unsettled. An general assumption, not proven..
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        • Posted by salta 8 months, 1 week ago
          Yes, and my point agrees with the wording in that definition.
          It is only a partial definition though. To be given this high status (of "Theory") the principle must also specify the observations that would disprove it. If that happens, the principle is knocked off its Theory pedestal, and is just referred to in ways like... "in the past we once thought such-and-such"
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    • Posted by  $  MikeMarotta 8 months, 1 week ago
      A theory is just some airy ideation. It is - as you noted - an explanation of fact. Observable facts that cannot be explained are called anomalies. From A-Noma: not standard; not namable; not managed, etc..
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  • Posted by ycandrea 8 months, 1 week ago
    Evolution was a theory based on information we had at the time and then embellishments were added. It was never a fact. I have always guffawed at the wild times lines claimed and at the very process of us mutating from other species. It just did not make sense to me. Whatever you believe about the creation of Earth, whether by God or The Big Bang Theory, our whole planet was made up of materials from other planets. So it stands to reason that some of the "stuff" found buried deep in the dirt did not get here after our planet was formed, but before. Which in turn means that it does not reflect historical data of THIS planet Earth.
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