Is evolution a fact or theory?

by sleepy 41 Replies latest jw friends

• 

  sleepy

  Is evolution a fact or a theory?
  I suppose it depends on what you mean.
  Evolution in the sense of change from one generation to the next seams to be fact.
  Is well observed that offspring from a given creature will differ from the parent in different ways and thus after many generation can come to be quite different.
  Also that the genes of a creature can be affected by radiation from the sun and be alter in a novel way producing new and unique features in its offspring ( as long as the mutation is in the sperm or the egg).
  That we came about via changes in the genes that eventually created a very different creature than that existed many generations ago , is that a fact?
  This requires that not only that there are changes between generation but also that these changes could be directed by different environments to such a degree that only certain specialised features could survive and reproduce offspring whilst other creatures have died out and only remain in fossilised form.

  What evidence is there that such environments can and have existed?
  Can we know that an environment existed that for example to allow mathematical ability to flourish in humans while all who couldn’t do sums died out?
  Can we account for all parts of the human body or that of any other creature by means of various environments that would select and hold their various features at the expense of other features or animals.
  Can we specify an environment for each part of a creature and why it would chose a particular novelty over another.
  Or are we suggesting that this could have happened but we don’t know how, in which case it is a theory.

  Evolution is not just about the changes in animals over generations but also involves specifiic envionments having been in existance in order for it to work to the degree nessesary to acount for life today.
  And remember even thought evolution can produce changes in offspring so can intelligence.
  Humans can do that today .
  So how do we know that some intelligence hasn’t acted in the past to direct what creatures live on this earth?
  Isn’t saying that there were environments that caused the complexity in creatures that exist today just as unsubstantiated as the belief in a creator .
  Yes evolution can be shown to work to some degree ,even to a high degree in some circumstances but can we know for sure that there were conditions available on this planet to produce the abundant variety and complexity of life on earth today?

  Also what is consciousness?
  If we don't know what it is how can we say we know how it was made?
  Is consciousness just the result of the mechanisms in our brain or does consciousness use the physical brain in order to exist?

  We know we receive information on vision through our eyes and this is processed in the brain ,we can check this by observing what happens to people who have damage to there eyes or brain and noting what happens to them.
  If your eyes are damaged you cant receive vision .
  If the part of the that interprets what is received by your eyes is damaged you cant interpret vision or see.
  But could you still imagine vision in your head?
  What is it that actually sees or hears or tastes?
  Correct me if I’m wrong here, also on the above , but can we lose our qualia ( I think that’s how you spell it) that’s our sensations of experiences , sight ,sound etc in our head our imagination apart from dying ,is there an accident that can cause me to lose the ability to imagine or compose a song in my head?

  Whether that is true or not, consciousness is not well understood .It is the MAIN part of what identifies a human being if we don’t know what it is or how it works how can we say it evolved?
  I feel this is the main reason people chose to belive in a creator not the complexity of life but consciouness.
• 

  FrightMare

  I take my philosophical starting point as roughly in accordance with Searle, but a bit more "hard AI" in some ways. In other words: Conciousness is not a thing, but a function of the brain, in the same way that the circulation of blood is not a thing, but a property of the vasculature and heart. It is thus neither an object, nor a non-material entity, but a property which an object posesses. In this view point, the "problem" of qualia is not an insurmountable puzzle for conciousness, but simply a description of part of the concious state. The major difference between conciousness and all other visceral functions is that we view (erroneously) a combination of language and entirely subjective states to discuss the visceral function, forgetting that language and subjective states are the visceral function. It is a cognitive trap that is subtle and elusive.
  Penrose, and all the other "spooky" theorists of conciousness avoid several facts:

  1. Conciousness is made of parts, and lesion studies show that in humans. Concious experience is not bound into a seamless whole: things are at the edge and the center of experiance depending on circumstances, and circumstances will also cause things to intrude that are not objectively real (hallucinations) and cause objectively real phenomena to drop out of sight (Chronic pain is no longer noticed except as irritability).

  2. The brain has a specific architecture, and lesions in the brain cause specific syndromes. These syndromes are best explained by the activity of neurons in those areas, and their anatomical connections. These lesions can also alter the capacity of objects to enter the concious arena, and the capacity of the brain to perform tasks employed by the concious mind (ie they limit the sphere of conscious experiance). Hence, any theory of consciousness must explain these two facts in detail.

  The microtubular theory proposes that somehow the thalamic 40hz scanning frequency is necessary for the coherence function of the microtubular arrays. This does not address in any way adequately the fact that much of our concious experience appears to be mediated by overlapping circuits between cortical areas: the function of many thalamic nuclei are more plausibly scanning, switching and weighting of functional importance of cortical and subcortical circuits, rather than a spooky source of quantum coherence. If the theory is so modified as to say that the actions of the thalamic mechanism is reflected by neuronal activity, then all you have to do is remove the quantum coherence bit, and you have the same explanation as the usual neurobiological one, but simply lacking the quantum stuff, and since the necessity of invoking quantum coherence on neurobiological grounds is not clear at all, the whole thing becomes somewhat pointless.

  In brief, the only sensible neurobiological approach to conciousness is NOT that it is a manifestation of an event or a thing: it is first and foremost a subjective state. But that is a surprisingly subtle and tricky point: it is a subjective state in an organ that appears to have as its function the generation of particular subjective states, in the same way that blood circulation is a phenomenon in an organ whose function seems to be the maintenance of a particular pattern of circulation. If it were otherwise, then the heart (with its pacing, and its intrinsic microtubules) would be "conscious", and so would the bowels (with their truly substantial innervation and intrinsic pacers). But they don't manifest signs of experiancing subjective states in the same way that brains do, even though they surely have both microtubules and a complex architecture and intrinsic pacing. So........

  What does this have to do with evolution? Once you work out what conciousness actually is, then that defines the scope of both its consequences and origins. So all of this it has to do with the idea of specified complexity but it also bears directly and simply on the notion of Intelligent design. Let us now consider the simple idea that conciousness is a prerequisite for the activity of intelligence. Hence conciousness is a prerequisite for design. Now, conciousness is a subjective state of a material brain of some sort (that's our definition). That is the only way we know of it, or can define in it any scientific terms (that's a scientific fact). It is thus impossible in the strongest terms to speak of ID without implicitly assuming a material brain of one form or another. I think we all know what that implies for theists of any type: that if G-d is the designer, G-d has a material brain. If G-d had a material brain, then He would be a natural phenomenon (by definition). Seems to me only a very naive person would accept the notion of ID as scientific evidence of Divine intervention.
• 

  funkyderek

  This requires that not only that there are changes between generation but also that these changes could be directed by different environments to such a degree that only certain specialised features could survive and reproduce offspring whilst other creatures have died out and only remain in fossilised form.
  What evidence is there that such environments can and have existed?

  Different environments exist now and creatures exist which are adapted to their environment. It's an aphorism that creatures which are not suited to their environment will die out.

  And remember even thought evolution can produce changes in offspring so can intelligence.

  But intelligence would normally do it in a more intelligent way. It seems pointless for an intelligent creator to spend billions of years creating, destroying and re-creating life forms, only to end up with imperfect creatures full of vestigial organs and junk DNA.

  Is consciousness just the result of the mechanisms in our brain or does consciousness use the physical brain in order to exist?

  Could be either, but it appears in every measurable way that consciousness is a function of the brain and nothing more. When the brain is damaged, consciousness is affected. Also, there is no known way for a "spiritual" consciousness to interact with the physical brain without leaving some evidence of the interactions. In the absence of the extraordinary evidence necessary for the supernatural explanation, the sensible option would be to assume that there is a natural explanation, even if the details currently elude us.

  Correct me if I’m wrong here, also on the above , but can we lose our qualia ( I think that’s how you spell it) that’s our sensations of experiences , sight ,sound etc in our head our imagination apart from dying ,is there an accident that can cause me to lose the ability to imagine or compose a song in my head?

  A lobotomy can remove emotions, rendering a person unable to make the simplest of decisions. People whose brains have been damaged in accidents often make full recoveries, but with completely different personalities. I heard of at least one case where brain damage resulted in a person not only being unable to see, but having no concept or memory of sight, even though there was nothing physically wrong with her eyes.
  If you're interested in this subject, I suggest you read the following books:

  The Man Who Mistook His Wife for a Hat by Oliver Sacks, a fascinating book about bizarre neurological disorders.

  The Meme Machine by Susan Blackmore, exploring the idea of memetic evolution (a meme being a self-replicating idea analogous to a gene).

  On evolution in general, anything by Richard Dawkins is a good start.

  --
  Those who can induce you to believe absurdities can induce you to commit attrocities - Voltaire
• 

  sleepy

  Some extra thoughts on environments.
  I am in a learning stage and will only benifits from the opinions from persons who are more more educated in this subject.Even if they make me look like an idiot.
  Creatures that are not suited to their environment will not only die out but move out.

  Environments come in many different sizes from islands to continents. If a creature finds that conditions have changed he will move elsewhere .If he is in an isolated area say surrounded by hills then maybe he cant and will die out. Many different types of animal can exist in the same environment as in each environment there can be many different resources that can be used by various creatures .A creature may specialise in one but could cope in another so will not die out easily.
  It is easy to imagine a major event such as a comet strike killing out many species and leaving some that could cope, but remember the survivors had coped in the previous environment too.
  Evidently creatures are able to cope with some change.
  There needs to be some competiton among creatures in order to create a battle for survival. Would say a giraffe having a long neck cause shorter versions to die out ?
  Well all giraffes start out as babies and have shorter necks they are not made extinct by their parents better reach. Where is the battle for survival between baby giraffes and adult.
  To explain all most each part of a creature we are asked to envisage a battle for survival yet this does not always exist in nature nor can it alone explain many of the specifications found in nature.
  Unless someone can show how specific environments can cause certain creatures to die out without any option of moving or getting on along side competing creatures then this part of evolution seams to be very much theory.
• 

  SixofNine

  To explain all most each part of a creature we are asked to envisage a battle for survival yet this does not always exist in nature nor can it alone explain many of the specifications found in nature.

  I'm pretty new to thinking about evolution in a serious way myself, but perhaps you should be playing your battle scenes in much slower motion?
• 

  sleepy

  SixofNine

  I konw the amount of time involved, but at some point one type of creature is surviving and then it is not.
  At some point there would have to be a direct conflict between the different tpyes of creatures over resources .
  For instance if the earth gradualy dropped in tempreture over 1000's of years there comes a critical point when the condisions become too much for certain animals.
  How long does that critcal point last.
• 

  Amazing

  Simply put, Evolutionary Science is like any other sicence in that it is a 'Working Theory' supported by facts. Similarly, 'Electrical Theory' is supported by a strong body of facts and laws. 'Gravitational Theory' is likewise supported by facts and laws. Evolutionary Theory is a powerful foundation for biology and how humans are related to non-human ancestors, and medical science also depends on it greatly. Evolution, therefore is factual.

  The issue for most religious people of one or another type of Theism is whether God is the source and designer of Evolution, or if Evolution occurred without any Divine involvement. Evolution is a proven fact, but does not require that one discard God or accept God. The issue of God as creator is a matter belonging to theologians and philosophers.

  I believe in God and I understand that Evolution is factual. So, I have to believe that God is the source of the evolution of all species. It almost seems fitting that God would design the process such that it insures survival of species by allowing each to grow and change over time.

  The problem that most fundamentalists have is that either they believe in 'Young Earth Creation' which forces them to rule out Evolution, or they make a literal interpretation of the Bible - really forcing interpretations upon it that it does not demand - cause them to say that God zapped us into existence without any evolutionary process. They have fallen victim to the concept they themselves created that Evolution = No God. Science never demanded such.

  Most folks who try to play upon the word "Theory" fail to distinguish between "speculation" or "hypothesis" and science built upon facts to form 'Working Theories or Principles". They take the word 'Theory' out of its scientific context and use it in a narrow limited way to grasp at straws in fighting the flood of facts that support Evolution.

  Amazing
• 

  AlanF

  To sleepy:

  The fact that you're posing this question at all shows that you really, really need to do a lot more reading up on the subject of evolution and learn much, much more -- far more than you can hope to get from a discussion forum. The available resources are immense, on the web and in written literature.

  Evolution is both a fact and a theory. The precise thing one means by "evolution" depends on the context of the discussion.

  In the sense of "change of populations over time" evolution is as much a fact as the best-established facts of non-written history. It is a fact that there was once a Mediterranean volcano called Santorini that erupted around 1600 B.C.E. and wiped out the Minoan civilization. How do we know this? Through a great deal of inference from geology, archaeology and a bit of written history from surrounding nations. The evolution of populations is no different. The fossil record, paleontology and geology combine to prove conclusively that populations of plants and animals have changed (evolved) drastically over the last billion years.

  From the fossil record we learn that life has undergone a number of major and minor extinctions. The greatest extinction of all, at the end of the Permian period some 225 million years ago, wiped out around 95% of all species. The extinction of about 65 million years ago wiped out all dinosaurs and a lot of other life as well. Both of these extinctions are accompanied by substantial changes in the geology of the sedimentary rock above the level of the extinction. At the boundary of the dinosaur extinction, for example, is found an unusual layer containing extremely high amounts of the element iridium, which is found in such abundance in meteorites. The layer also contains a great number of particles of shocked quartz and soot. All these things strongly suggest that an asteroid struck, generating massive amounts of airborne rock powder and a worldwide firestorm. After this event, a great explosion in the number and kind of mammals and birds occurred. The same pattern is seen in the Permian and other large extinction events -- a great extinction followed by an explosion of new life forms. This pattern is by definition evolution.

  In the sense of "theory" evolution comprises many attempts to explain the above facts by various means, from Darwin's notion of "survival of the fittest" to more modern notions that include genetic drift to Gould & Eldredge's notion of punctuated equilibrium. Some Christians pose other theories that include the idea that God directed evolution, either by direct creation of new species after wiping out older ones, or by a process indistinguishable by us today from non-theistic evolution.

  Many people don't understand the above ideas. They lump everything into a monolithic notion of "evolution" which they simply don't understand. JWs and Young-Earth Creationists are among these, and their ignorance (in fact, their love of ignorance) is shown by the fact that no matter how many times these facts are pointed out to them, they refuse to understand. They say, "evolution is God-dishonoring" when in fact, according to plenty of Christians who actually understand evolution, it honors God. What could honor God more than acknowledging his method of creation, if in fact the geological record is a good record of the history of life? For people who respect science, Christian or not, the fact of evolution is not a problem at all, while various theories of evolution are up for grabs.

  AlanF
• 

  Jeremy Bravo

  Alan,

  What are some good resources to read up on this stuff? I'd love to but don't know where to start.

  Thanks,
  Jer.
• 

  sleepy

  I have read a lot more about evolution and its workings than I can express here.
  Yet I still remain unconvinced in the idea that it could have ,in its current form of acceptance most have been responsible alone for what we see on earth today.
  Evolutionists often accuse those who doubt of creating a “straw man” to attack when they try to refute neodarwinisum.
  But I find that evolutionists sometimes are worse at this.
  Often I find in their arguments against doubters they offer suggestions as to what one most surely believe if you don't find the whole concept of evolutionary theory acceptable.
  You find ideas about what a God must be like or that you most believe the earth is young or you don't believe mutations can bring change etc.
  Also I have heard it said that since someone has no better idea to offer why criticise current belief.
  That reminds me of when witnesses say “where else shall we go?”

  But the hole issue is more complex than believing either one set of maxims or the other.
  Change is a fact ,what change can accomplish in any given environment is not fully known.
  I have often seen presented the idea that given enough time anything is possible. So you have the idea that if you sat down hundreds of chimps at typewriters and gave them enough time they would eventually come up with the complete works of Shakespeare.
  This is not true.
  Although this is a conceptual reality it is not necessarily a practical one in the sense that a lot more things are involved other than the chance aspect.
  In order for random or chance events to have the ability to have infinite or very large variation ability certain mechanisms need to be in place.
  The chimps for example would need paper, type, writers ,ink the desire to press the keys ,the ability to live a long time or be replaced, some method of selection would also be needed to select the correct written work and to judge when it is accomplished.
  So although the concept that given enough time anything can happen is true , practical considerations can drastically curtail the effectiveness of chance.
  Another example is of a box part filled with small balls.
  If you vigorously shake the box will the balls over a great period of time be able to explore each and every part of the box?
  Well no for the available amount of movement of a ball is curtailed by the movement of other balls. So although many positions can be taken in the box by each ball not all are available to each one. Where they could go would be dependant on their starting configuration and the positions of other balls in the box.
  The point being that even though we can see that creatures have the ability to change over time the extent to which that can work is dependent on certain other practicalities.
  To say that we know all the conditions ever present on earth is obviously wrong. So we cant say with certainty that the available conditions on a planet like earth are alone able to allow the kind of changes that must have taken place to turn non life in life and single cell into human.

  Chance and randomness in the non-quantum world are only concepts. Chance dose not make things happen but describes our inability to explain or predict why it happened.Things happen only when there is a mechanism to make it happen. Of course with evolution we are not asking for just anything to happen .
  But to say it can happen does not only involve the concept that over vast periods of time almost anything can occur ,but involves knowing what things can or can’t happen due to certain mechanisms.
  Two of which are natural selection and intelligence.

  If just in one case natural selection carnt explain how a feature arose then surely the current theory stands on shakey ground.