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Message: <blockquote data-quote="hafizsaad" data-source="post: 6074464" data-attributes="member: 153303">One big happy family :             Theory or hypothesis? Just as with abiogenesis, common descent is closer to being a hypothesis rather then a theory. And just like abiogenesis, it's strictly speculation at this point. There's no proof, no falsifiability and no testability. The hypothesis is based on the sweeping generalization that since some organism evolved from one another, all must have evolved from the same one! This is obviously a logical fallacy. But more importantly, one could argue that since this theory speculates on what happened in the past; that this is actually a history theory build on different scientific theories rather then a scientific theory itself! Irreducible complexity. The biggest problem of this theory is a concept recently coined as "irreducible complexity". This refers to an organism or part of an organism that is complex in the sense it has multiple components, components which by them self have no function. Because of survival of the fittest, useless components will not evolve. So the only way to account for all components trough evolution, is if all those useless components were created all at once to form a useful organism. That is why the organism is irreducibly complex; it has to have been created at once and cannot be reduced into multiple steps. Some evolutionists have tried to counter this argument by suggesting that components could have been borrowed from other organisms. However this doesn't cut the mustard. Only some of the components which need to be accounted for in organisms are shared with other organisms. Next to that, those shared components that are shared in multiple organisms are often borrowed form yet another irreducible complex organism. So in the end this still doesn't explain how a chemical molecule, which has no function when isolated, could have been selected trough the process of survival of the fittest. A much more detailed explanation of this, can be found in this Short movie: <a href="http://video.google.com/videoplay?docid=-5585125669588896670" target="_blank">Intelligent Design - Unlocking the mysteries of life.</a>From single-celled to multiple-celled organism. Lets pick up where we left of with abiogenesis. Say that for the sake of argument a single-celled self-nourishing and reproducing organism originated. How did it evolve into a multiple-celled organism?Remember how we talked about most prokaryotes using a very specific enzyme to convert methane out of hydrogen and carbon dioxide in order to harvest energy. Well all prokaryotes (organisms that do have organelles with membrane-boundaries) rely on a different more complex process called the tri-carboxylic acid cycle, or a.k.a. Citric acid cycle. This cycle is a 12-step chemical process. Each step relies on a different enzyme as catalyst, and each step is vital to the chain in order for it to eventually extract raw energy out fats, carbs and proteins. Of course these components need to be broken down by the digestive system first; which is a whole different story altogether. So by what process could one very specific process of energy harvesting evolve into a completely different, complex system? Remember that this is a vital characteristic of life, so an intermediate organism, that isn't able to harvest energy is out of the question. Building a second while the first is still functioning is also very unlikely, since each step wouldn't have any benefits for the organism so it can't rely on survival of the fittest.  Some other examples of irreducible complexity. This irreducibly complexity does not occur only on the chemical level, but can also be found on a much larger level; with organelles and organs, and even with complete biological systems or animal classes. Although I do grant that most organs and organelles could have evolved out of a more simplified version. At some point, these simplified versions would have some degree of irreducible complexity to. A common argument discussed in this line of argument is the eye. For the eye to do what it's suppose to, it needs several components, a lens, muscles to adjust it, light receptors, nerves, and so on... Recently a reply has been formulated by evolutionists that speculates on how mollusc could have evolved from eye-less to seeing, by intermediate steps. The speculation goes that it went from pigment rich skin, light sensitive spots, light sensitive cavities, light sensitive cavities with liquid in it and finally to light observing with liquid and a lens. And some of the needed intermediate steps have been found among the mollusc. However the speculation is incomplete. For the theory to work; each change should have been possible from a single genetic mutation. So is it possible for a snail to go from light sensitive to light observing cells and at the same time evolve the necessary neural changes for the light impulses to be registered, let alone to make sense? Some might reply, that they could have adapted to the new type of impulses. But somebody who claims that doesn't really understand what adaptation means. Adaptation in biology, is a variation on survival of the fittest. It explains how a feature can be preserved after it mutated. It does not account for the origin of the new feature. So replying to me that they could have adapted is like saying there was a secondary mutation to take care of it. Which brings me back to my original statement, that the organ is irreducible complex since it would have to rely on multiple mutations at once. Similar arguments can be made for all other steps, as well as for other organs and organelles. But more importantly, not only does common descent speculate that an organ like the eye evolved naturally against all odds, it also speculates that this unlikely event occurred multiple times for multiple species! The mollusc for example, are speculated to be from a different branch as the insects; so the evolution of molluscs eyes cannot be used to account for insect eyes, which are a lot more complex by the way. The same goes for other species like mammals; who allegedly formed eyes completely independently. And we can find irreducible complexity at yet an even larger scale when considering abilities of species. Certain abilities, like flying, breathing underwater, breathing above water, digesting, reproducing trough cell division, reproducing trough male and female, all these abilities rely on multiple organs, organelles and characteristics. That is to say that some animals, or at least some type of animals like fish, bird, mammals, reptiles,... are irreducibly complex. They requires multiple organs and features to do what they generally do. A single of those features does not have a function, and the ability requires multiple features.Other common flawed arguments. Having discussed the biggest challenge to common descent, let us consider some of the common flawed arguments in its defence. The most basic argument in favour of common descent is, that since so many animals are so similar, it's most likely that they evolved from one another. But just because things look alike doesn't prove anything. However I'll discuss the flaws of this type of argument in detail in the next section, so I'll leave it with that for now. Next to making comparisons, some try to enter the fossil record as proof for common descent. The argument goes, that fossils show up in certain layers of ground which in term are linked to certain eras in time. If you then make a timetable of which time the fossilized creatures lived in, it matches the timetable that common descent proposes. Well first of all, that's hardly any proof, all it does is proof which creatures lived at which time, it doesn't proof which evolved into which. Creationists might just as well claim that this proves at which time certain animals were created. The fossil record does not favour common descent over creation. In fact quite the opposite can be said, the fossil has many issues that reflect bad on common descent. Like the Cambrian explosion. An era where there's a sudden high concentration of entirely new species, as opposed to the slower pace of evolution in other eras. Another problem are the large number of missing links. There are so many proposed intermediate species missing, that some scientists have started suggesting that rather then evolution trough slow steps, there must have been "jumps" to. But that's of course very unlikely. A mutation that carries benefit is in itself unlikely, many mutations at once that carry some benefit is close to impossible. Other than that it needs to be noted that there's a lot of controversy regarding the accuracy of dating fossils. I wouldn't go as far as saying that it's all a hoax, like some Christian creationists claim. But lets just say it does indeed require a lot of work, and the margins of error are larger then usually admitted. A similar argument, is that if you make a tree of heritage, based on similarities in DNA between creatures, then you have more or less a similar tree to the tree of descent that common descent proposed. But this information is actually false. First of all, only the genome of 4 animals has been decoded so far. (Humans, chimp, mouse and fly). So we're far from making a thorough comparison, more detail about comparing DNA can also be found in the next section. Basically what they compare are karyotypes, not DNA. But even then, the argument is a false. When DNA was discovered, and they started comparing karyotypes, the tree of descent they formed based on this discovery actually contradicted the earlier proposed tree of descent rather then conforming it! So in a way this didn't make the theory falsifiable, but it falsified the theory. Of course the theory wasn't really falsified. They just had a fresh start for evolution and they had to revise the whole theory. So the current tree of descent is based on this comparison of karyotype, and not confirmed by it! However this teaches us an important lesson. The alleged tree of descent cannot be used as falsification for the concept of common descent in itself! No matter how many times you would falsify the tree of descent, proponents of common descent would be able to suggest new alternative trees. So since falsifying the tree doesn't defeat the idea of common descent, that means the tree of common descent cannot be used as falsification for the theory of common descent.Continuing..<img src="/styles/default/xenforo/smilies/default/yes.gif"  class="smilie" loading="lazy" alt=":yes:" title="Yes    :yes:" data-shortname=":yes:" /></blockquote>

Verification: Dawasata paya keeyak thibeda?

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