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Thread: Evolution - chance or causality?

  1. #1 Evolution - chance or causality? 
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    Is evolution a product of causality everything being predetermined by whatever created the rules by which physics works prior to the big bang or is evolution an interaction of that causality with random chance?


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    Quote Originally Posted by Chrisgorlitz View Post
    Is evolution a product of causality everything being predetermined by whatever created the rules by which physics works prior to the big bang or is evolution an interaction of that causality with random chance?
    Interesting question. But I would expect that given the same sequence of events that created our Earth and caused the same extinction events, we could expect very similar evolution on another world. One question I would like to have answered first before I might commit to that idea, is did life originate here on Earth or did it come from elsewhere and just germinate here on Earth when conditions were right? It's a question of the DNA all life on Earth has in common. Would it be the same everywhere life could exist or would it take on a completely different configuration?


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    Remember it's not "random chance". It's billions upon billions upon billions of random chances building on each other through billions of years.

    Just look at how long it took to get any kind of life started. A couple of billion years. How many billion chemical reactions had to 'fail' for each little marginally successful step along the path to multi-celled organisms?

    Then how long after that it took to move towards anything remotely like sexual(ish) reproduction. Another billion? How many hundreds or thousands of billions of dead ends, or complete non-starters, in those random chances that finished up as more complex life forms? Evolutionary history of plants - Wikipedia, the free encyclopedia

    We throw around concepts like "billions of years" too carelessly. We should sometimes stop and think just how long that really is. 200 million since flowering plants got started. It's "only" 65 million years since the dinosaurs went extinct. 40 million years for the grasses that eventually became our grain crops. We've been around in our current form for only a few hundred thousand years. And we've only had agriculture for a mere blink of an eye - starting 10000 years ago.

    And the richer the environment became in varieties of life forms, the more and more billions of random chances for development of more and more species of those living things.
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    Quote Originally Posted by Chrisgorlitz View Post
    Is evolution a product of causality everything being predetermined by whatever created the rules by which physics works prior to the big bang or is evolution an interaction of that causality with random chance?
    this question is too black-or-white
    of course there's some degree of causality involved, but the multitude of possible interactions make the outcome still seem random, or to express it better, have some degree of probabilistic outcome

    for one thing, mutations are random when considered against their utility of the organism's survival, there's a massive degree of variability in the epigenetic process from fertilised egg to newly born organism, and subsequent survival prior to reproduction also depends to some degree on the vagaries of your environment
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    Quote Originally Posted by marnixR View Post
    Quote Originally Posted by Chrisgorlitz View Post
    Is evolution a product of causality everything being predetermined by whatever created the rules by which physics works prior to the big bang or is evolution an interaction of that causality with random chance?
    this question is too black-or-white
    of course there's some degree of causality involved, but the multitude of possible interactions make the outcome still seem random, or to express it better, have some degree of probabilistic outcome

    for one thing, mutations are random when considered against their utility of the organism's survival, there's a massive degree of variability in the epigenetic process from fertilized egg to newly born organism, and subsequent survival prior to reproduction also depends to some degree on the vagaries of your environment
    While mutations are fairly random, only the successes will remain to fill the available niches. That part of evolution is determined by the environment and cannot be random. That same process will take place anywhere in the universe where it can happen.
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    Also, don't forget that there seems to be true randomness in QM, meaning some things can happen without a cause per se. They would still have outcomes within statistical bounds, but they are truly random none the less. That means that given the exact same starting point, we would not end up with exactly the same universe we have now.
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    Quote Originally Posted by KALSTER View Post
    Also, don't forget that there seems to be true randomness in QM, meaning some things can happen without a cause per se. They would still have outcomes within statistical bounds, but they are truly random none the less. That means that given the exact same starting point, we would not end up with exactly the same universe we have now.
    Are you saying the randomness will still happen within the physical laws of our reality? Also, does it make sense to bring QM into a discussion of evolution. I don't believe evolution is all that random. For instance, take the development of a technological species. I believe only the right set of conditions over time will produce a technological species. An example would be a water world without any land. No matter how smart any life form is, it's not going to be in an environment that will support the development of technology as we know it.
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    Quote Originally Posted by arKane View Post
    Quote Originally Posted by KALSTER View Post
    Also, don't forget that there seems to be true randomness in QM, meaning some things can happen without a cause per se. They would still have outcomes within statistical bounds, but they are truly random none the less. That means that given the exact same starting point, we would not end up with exactly the same universe we have now.
    Are you saying the randomness will still happen within the physical laws of our reality? Also, does it make sense to bring QM into a discussion of evolution. I don't believe evolution is all that random. For instance, take the development of a technological species. I believe only the right set of conditions over time will produce a technological species. An example would be a water world without any land. No matter how smart any life form is, it's not going to be in an environment that will support the development of technology as we know it.
    Well what it boils down to is 2 possibilities, a.) that everything that we see around us and indeed everything that happens is just a progression that started at the beginning of time, the law's of physics creating the laws of chemistry creating biology creating evolution.

    Option b.) That the new claims about heisenberg's uncertainty principle being wrong, turn out to be false and that we don't find any logical causality explanation for Quantum randomness. If this is this case then Evolution is the product of random effects upon causality, this means predeterism is out of the question along with any possible level of creationism. It would also mean that there is a huge possibility of variation of other lifeforms that may evolve on other planets to the point where it is much much more likely that extraterrestrial life will be very different to that of humanity.
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    Quote Originally Posted by arKane View Post
    While mutations are fairly random, only the successes will remain to fill the available niches. That part of evolution is determined by the environment and cannot be random. That same process will take place anywhere in the universe where it can happen.
    granted that the outcome of natural selection is far from random, there's still enough variability in the outcome to deny a full deterministic outcome
    the constraints on development may be such that evolution may come up with similar solutions, but different in detail - it's often that detail which shows that convergent evolution is not homologous
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    Quote Originally Posted by marnixR View Post
    Quote Originally Posted by arKane View Post
    While mutations are fairly random, only the successes will remain to fill the available niches. That part of evolution is determined by the environment and cannot be random. That same process will take place anywhere in the universe where it can happen.
    granted that the outcome of natural selection is far from random, there's still enough variability in the outcome to deny a full deterministic outcome
    the constraints on development may be such that evolution may come up with similar solutions, but different in detail - it's often that detail which shows that convergent evolution is not homologous
    Yes, where would we be without the extinction process, and there's never a guarantee that any extinction will happen when needed is there?
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    "causality"? What does this mean? Does it mean "with a particular outcome imposed?" A particular out come is imposed by the laws of nature. We study nature to understand those laws so we can predict the imposed outcomes. But the imposition is limited by hiesenberian uncertainty.

    "Physics before the big bang"? "Before the big bang" is a meaningless phrase. Time begins with the BB. Physics before the big bang is the same as saying "physics outside our universe". Before the big bang is out side our universe in the temporal direction.

    Ramdom is the name of the game, but "random behavior" is just the same as "having free will" seen from the opposit end of the telescope. What we precieve as our chosen acts when we do something, is seen as random behavior when seen en mass. 10 million individuals doing what they chose looks exactly like 10million individuals behaving randomly.
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    Quote Originally Posted by Sealeaf View Post
    "Physics before the big bang"? "Before the big bang" is a meaningless phrase. Time begins with the BB. Physics before the big bang is the same as saying "physics outside our universe". Before the big bang is out side our universe in the temporal direction.
    Only if you think the current BB theory is a done deal. But for the sake of an alternate idea. What if the BB is a natural event that takes place in a very much larger structure than our current universe?

    1. "Before the big bang" now has meaning.
    2. "Time begins with the BB" now only applies to our local universe.
    3. "physics outside our universe" Outside of our local universe? Not a problem for me.

    How big would a structure have to be for us not to be able to detect or perceive it? When you consider infinity, it becomes easy to think outside the universe.
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    Quote Originally Posted by Sealeaf View Post
    "causality"? What does this mean? Does it mean "with a particular outcome imposed?" A particular out come is imposed by the laws of nature. We study nature to understand those laws so we can predict the imposed outcomes. But the imposition is limited by hiesenberian uncertainty.

    "Physics before the big bang"? "Before the big bang" is a meaningless phrase. Time begins with the BB. Physics before the big bang is the same as saying "physics outside our universe". Before the big bang is out side our universe in the temporal direction.

    Ramdom is the name of the game, but "random behavior" is just the same as "having free will" seen from the opposit end of the telescope. What we precieve as our chosen acts when we do something, is seen as random behavior when seen en mass. 10 million individuals doing what they chose looks exactly like 10million individuals behaving randomly.
    The why things work the way they do is the point, the whole universe is dictated by the laws of physics, they existed before anything else, causality is a product of these laws one thing follows on from another cause and effect, understanding this is understanding all the chain of events that led to where we are. Randomness is where one cause can have a number of different possible outcomes with no particular reason for one outcome or another. The problem with randomness is why would it occur in some things and not others.
    For example a law of physics may tell us that a particular result will always follow a particular cause, this is fine and easy to understand as it's straight forward causality in effect, things get tricky when you introduce randomness though because then any outcome may result from the same cause. So why is that tricky? It's tricky because if true randomness does indeed exist we a presented with the question why only sometimes? Why does randomness only appear in certain things and not everything? If it appeared in everything then we wouldn't have any causality there would be no logical effect being the same from the same cause, so we wouldn't have any laws of physics, chemistry or anything else.
    So back to randomness, what could determine one thing being random and another thing not, this somewhat problematic again because this determining factor must be fixed not random because if it's not then anything can end being determined as random, which is clearly not the case. Now if the determining factor is fixed it must also be a product or causality. So even if randomness exists it has to be caused ultimately by causality, leading us full circle to ask if this randomness is really random at all or just a trick of causality.
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    Strange attractor, anyone? Chaos, randomness, whatever, is still constrained.
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    i was wondering...is evolution driven soley by random mutations to dna? the reason why i ask is because i have a hard time believing that behaviour aspects contained in dna are randomly derived. for example, take a spider knowing how to weave its web. this is such a complicated set of instructions. i can't even begin to calculate the probablility of these instructions occurring in dna by chance. before we happened to come accross this sequence by chance, nature would have to experiment with behaviour to an unbelievable extent...and you would see spiders, as well as other animals, engaging in all sorts of 'wacky' behaviour before hitting upon something like this. but i don't see that in nature. in fact, i see the behaviour of animals to be rather stable. you don't see giraffes kicking their hind legs trying to spin a web, or squirrels jumping out of trees because they think they can fly, or monkeys drowning themselves because they think they can breathe underwater. but rather, the behaviour contained in an animal's dna closely reflect the physical abilities of that creature. any thoughts on how this portion of dna gets written? thanks in advance
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    Quote Originally Posted by mrjc99 View Post
    i was wondering...is evolution driven solely by random mutations to DNA? the reason why i ask is because i have a hard time believing that behavior aspects contained in DNA are randomly derived. for example, take a spider knowing how to weave its web. this is such a complicated set of instructions. i can't even begin to calculate the probability of these instructions occurring in DNA by chance. before we happened to come across this sequence by chance, nature would have to experiment with behavior to an unbelievable extent...and you would see spiders, as well as other animals, engaging in all sorts of 'wacky' behavior before hitting upon something like this. but i don't see that in nature. in fact, i see the behavior of animals to be rather stable. you don't see giraffes kicking their hind legs trying to spin a web, or squirrels jumping out of trees because they think they can fly, or monkeys drowning themselves because they think they can breathe underwater. but rather, the behavior contained in an animal's DNA closely reflect the physical abilities of that creature. any thoughts on how this portion of DNA gets written? thanks in advance
    To answer your question, I'd have to say evolution is not driven solely by random mutations. Environmental pressures play a big part driving evolutionary change. I'm not really up on all the genetic terminology, but I'll try to get my point across. Every life form has more genes in their DNA that seem to be inactive or play no roll for that organism than genes that do have an active roll. One of the current theories being developed is that those genes come into play when the organism needs to change to fill an available niche or change with the environment to survive. When the environment changes some niches are closed out and new ones are opened up. When a species can no longer compete it goes extinct and other species that can compete for the new niches buy the time to change and adapt. Another environmental pressure that drives evolution is the relationship between pray and predator. In the pray animals only the ones that are the strongest best able to avoid the predators are the the ones that breed the next generation. If the predators can't keep up by getting stronger and faster they will starve to death.

    Anyway those genes which don't appear to be used for anything can be switched on and others that are being used can be switched off, and this has very little to do with random mutation. Beyond this point I'm fairly lost.
    Last edited by arKane; October 24th, 2012 at 09:04 PM.
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    i was wondering...is evolution driven soley by random mutations to dna?
    To put ArKane's point another way, if DNA (and the relevant organism) is to survive in a changed environment, having a good range of random mutations is the way to go. It gets colder or warmer, a certain population of prey or predator increases or decreases, new plants/fungi/insects move into an ecosystem. For any combination of such changes, the species with more variations in DNA have more chance of survival. Individuals with less well suited traits and features may die out, but the species survives.

    It may be smaller or larger or taller or stronger or more resistant to disease. It may abandon or develop hibernation habits appropriate for icy or desert conditions. A plant may tolerate new competitors or parasites or concentrate a toxin to discourage them. Whatever the change, the species only survives because enough individuals had whatever it takes to survive, or thrive, in the changed conditions.
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    i want to thank you guys for your responses. but i guess i didn't make it clear enough what i was looking for. i'm wondering if an animal learns a behaviour (not contained in its dna) that helps it survive, is it possible to incorporate this knowledge in its dna and pass it genetically to its offspring. obviously this doesn't happen all the time, and clearly doesn't happen in animals that learn life's lessons from its parents...but i'm wondering if it ever happens. going back to the example i mention above...at some point in time, spiders started to pass along the knowledge of spinning a web in its dna. this is a very complicated set of instructions that i'm sure requires many bits of information. for this information to occur in dna by chance seems highly unlikely. because i don't see random behaviour in animals. i see relatively predictable behaviour in animals. i.e. i don't see the random variations in the behaviour genes on a scale that would possibly produce a set of instructions this complex by chance. any thoughts? thanks.
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    Quote Originally Posted by mrjc99 View Post
    i want to thank you guys for your responses. but i guess i didn't make it clear enough what i was looking for. i'm wondering if an animal learns a behaviour (not contained in its dna) that helps it survive, is it possible to incorporate this knowledge in its dna and pass it genetically to its offspring. obviously this doesn't happen all the time, and clearly doesn't happen in animals that learn life's lessons from its parents...but i'm wondering if it ever happens. going back to the example i mention above...at some point in time, spiders started to pass along the knowledge of spinning a web in its dna. this is a very complicated set of instructions that i'm sure requires many bits of information. for this information to occur in dna by chance seems highly unlikely. because i don't see random behaviour in animals. i see relatively predictable behaviour in animals. i.e. i don't see the random variations in the behaviour genes on a scale that would possibly produce a set of instructions this complex by chance. any thoughts? thanks.
    The way the spider brain is put together is coded in the DNA and it gets passed on to the next generations. But I don't want to even try to guess how this came about in the first place. Also, when you think about the many thousands of species of spiders there are and they all make silk and use this ability differently. So I would guess from the spiders point of view this was a very advantageous evolutionary adaptation. I'm just guessing but when a physical change in an organism takes place, such as the ability to make silk, a corresponding change takes place in the brain that allows the organism to instinctively know how to use this new ability and also pass it on to future generations.
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    if an animal learns a behaviour (not contained in its dna) that helps it survive, is it possible to incorporate this knowledge in its dna and pass it genetically to its offspring.
    When you put it like that it sounds too much like Lamarckian inheritance of learned behaviour. Seeing as Lamarckian inheritance of physical characteristics is off the table, so would this be.

    The only remotely similar thing is the migration to ecological niches driving some animals to differentiate along adaptive lines. If you look at the various differences between spiders and their use of thread. Some create gigantic symmetrical webs between large trees. Redbacks make a messy tangle of 'web' in highly confined spaces, like the under the edge of a potplant or a toilet seat. Australian funnelwebs line a nest within the soil with their threads. Other funnelwebs make funnels in the open air. And then there are spiders that make lassos.

    None of these behaviours are learned, let alone taught. Individuals that survive in various environments are the ones who just happen to succeed and produce young when they use certain innate tendencies to make (or not) webs in particular ways. The more individuals succeed, the more that particular species will display that particular strategy for feeding or mating.
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    thanks again guys. just for the record, i do not have a biology background. i'm just somebody who is interested in science and wants to increase my understanding of things. so i kindly ask for your patience. arkane, you used the word "instinctively", and adelady uses the phrase "innate tendencies". but i see these terms as referring to behaviour and/or knowledge that the spider has inherited, and is warehoused somewhere, whether in the spider's dna or some other mechanism. my question is how did this information originate and subsequently passed on. adelady, i researched lamarkian inheritance, and i see where you are coming from. too bad, though. because that is exactly what i would have intuitively guessed was the case. however, fwiw, i did come accross this passage in wikipedia:

    "Interest in Lamarckism has recently increased, as several studies in the field of epigenetics have highlighted the possible inheritance of behavioral traits acquired by the previous generation."

    i could be wrong, but i get the sense that lamarckism could still be possible. i just don't see nature experimenting with behaviour to the same degree as physical characteristics. anyway, thanks again for all your help...and if you have anything more to add, i would love to hear. regards.
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    I rather doubt that Lamarckian inheritance will get any support. Once the research on epigenetics gets more runs on the board, I think people will come round to the view that that's why Lamarck's ideas had their initial attraction.

    The discovery that things like starvation in one generation of women can affect 2 generations and then go away merely shows that genes and their expression are much more complex than they were initially thought to be. Not that inheritance is a different mechanism altogether.
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    Quote Originally Posted by mrjc99 View Post
    knowledge of spinning a web in its dna. this is a very complicated set of instructions that i'm sure requires many bits of information. for this information to occur in dna by chance seems highly unlikely. .
    I just want to point out that even though a spider's web (all variations thereof) is a very complex structure, it doesn't necessarily have to be that complex genetically. The immune system is an example of where a huge amount of phenotypic variations can be produced by a relatively small and simple section of DNA. It is therefore not so far fetched to speculate that all kinds of spider webs can be produced by relatively simple genetic instructions. I can imagine something like a genetic algorithm that induces relatively simple behaviour in spiders that eventually leads to a web being spun. The spider has no idea of the "big picture" he's producing, but just follows a simple set of almost algorithmic steps that leads to the intricate structure. Small changes to this basic genetic code can then account for the variations in webs.

    If this is true, it is easier to imagine how this could have evolved. The selection wasn't for a huge amount of genetic information ("instructions"), but rather for a much smaller than expected piece of DNA.
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    Quote Originally Posted by adelady View Post
    I rather doubt that Lamarckian inheritance will get any support. Once the research on epigenetics gets more runs on the board, I think people will come round to the view that that's why Lamarck's ideas had their initial attraction.

    The discovery that things like starvation in one generation of women can affect 2 generations and then go away merely shows that genes and their expression are much more complex than they were initially thought to be. Not that inheritance is a different mechanism altogether.
    I agree. Epigenetics is interesting and somewhat changes the way we initially thought traits were inherited, but certainly wouldn't bring Lamarckism back.

    mrjc99, remember that epigenetics refers to a short term change to the "outside" of the DNA. It doesn't actually change the genetic code that is being replicated over thousands and thousands of generations.
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    [QUOTE=Gerdagewig;361331]
    Quote Originally Posted by mrjc99 View Post
    knowledge of spinning a web in its dna. this is a very complicated set of instructions that i'm sure requires many bits of information. for this information to occur in dna by chance seems highly unlikely. .
    I just want to point out that even though a spider's web (all variations thereof) is a very complex structure, it doesn't necessarily have to be that complex genetically. The immune system is an example of where a huge amount of phenotypic variations can be produced by a relatively small and simple section of DNA. It is therefore not so far fetched to speculate that all kinds of spider webs can be produced by relatively simple genetic instructions. I can imagine something like a genetic algorithm that induces relatively simple behaviour in spiders that eventually leads to a web being spun. The spider has no idea of the "big picture" he's producing, but just follows a simple set of almost algorithmic steps that leads to the intricate structure. Small changes to this basic genetic code can then account for the variations in webs.

    If this is true, it is easier to imagine how this could have evolved. The selection wasn't for a huge amount of genetic information ("instructions"), but rather for a much smaller than expected piece of DNA.[but if such simple changes in dna could result in such distinct aspects of behaviour, then i would expect much, much greater divergence of behaviour among animals. but again, i don't see such experimentation in behaviour occurring in nature. even arcane above notes a link between instinctive behaviour and corresponding physical attributes. if spinning a web instructions occurred by chance, it is very convenient that it just so happened to occur in a spider's dna. you never see a giraffe, or any other animal for that matter, kicking its hind legs trying to spin a web. as noted above, imho, if nature experimented with behaviour to the same extent as physical attributes, i would expect to see all sorts of bizarre behaviour among animals. but that's not the case as far as i can tell.]
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    sorry, i'm not familiar with how to quote on this forum. my message abover reads like this:

    but if such simple changes in dna could result in such distinct aspects of behaviour, then i would expect much, much greater divergence of behaviour among animals. but again, i don't see such experimentation in behaviour occurring in nature. even arcane above notes a link between instinctive behaviour and corresponding physical attributes. if spinning a web instructions occurred by chance, it is very convenient that it just so happened to occur in a spider's dna. you never see a giraffe, or any other animal for that matter, kicking its hind legs trying to spin a web. as noted above, imho, if nature experimented with behaviour to the same extent as physical attributes, i would expect to see all sorts of bizarre behaviour among animals. but that's not the case as far as i can tell.]
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    one other thing that makes sense to me. from a perspective of survival, it is far more advantageous for an animal to act 'with pupose' than for an animal's actions to be directed by chance. so i would imagine that if learned behaviour could be passed along, this trait would be superior than accidental behaviour being passed along. wouldn't you agree? and consequently, this ability would have been acquired at some time within the framework of natural selection.
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    Quote Originally Posted by mrjc99 View Post
    one other thing that makes sense to me. from a perspective of survival, it is far more advantageous for an animal to act 'with pupose' than for an animal's actions to be directed by chance. so i would imagine that if learned behaviour could be passed along, this trait would be superior than accidental behaviour being passed along. wouldn't you agree? and consequently, this ability would have been acquired at some time within the framework of natural selection.
    There are probably a lot of abilities one can imagine that might have been advantageous to an individual, if only they were possible in reality. The reality in this case is that there is no mechanism by which a learned behavior can be acquired genetically to be thereafter transferred to all future generations. It just doesn't work that way. The way it works is that the genetic code, in extremely complex ways, determines behaviour, not the other way around. Random changes to the code over millions of years produce small changes in behaviour that either improves the survival of the individual or not. In this way new patterns of behaviour eventually permiate the whole species, irrespective of what individuals might "learn" in their lives. Also, I think you look at this the wrong way around. Any learned behaviour already falls within the scope of what the genetic code of that individual allows, so there really isn't any reason for the code to change. The fact that an individual was capable of acquiring certain "skills", indicates that the genetic code of that species, under a specific set of conditions, can produce that specific behaviour. The behaviour therefore has nothing to change in the code, because it already exists there.

    Also, I'm sure that if I put my mind to it, I would be able to come up with a good argument for why your view that the ability to pass acquired knowledge on to future generations would have been far more advantageous to animals, is wrong. Off the top of my head I can come up with things like; 1) Such an ability would imply that species would change so fast that it would probably not have been possible for a stable eco-system to exist. Just think of the myriad of relationships that exist in nature, all dependent on certain balances and interactions within certain "normal" levels. If all of those components that fit so well start changing rapidly, the system as a whole would probably collapse. 2) Species would diverge extremely quickly if what you say is true. A species would continually split up into new species, dependent on certain local conditions. Since this isn't the case in nature, it proves that the ability you imagine doesn't exist. 3) If species could change so quickly to become extremely specifically adapted to their environment, it could imply that their adaptability to sudden environmental shocks become less (because the overall genetic variation of the species would probably become less during such extreme adapting to specific conditions), leading to extinctions every now and then when the environment changes significantly.
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    Quote Originally Posted by Chrisgorlitz View Post
    Is evolution a product of causality everything being predetermined by whatever created the rules by which physics works prior to the big bang or is evolution an interaction of that causality with random chance?
    In considering an ultimate causality, I like to use the word Potential (n). While this may seem to apply only to physics, there is a more fundamental quality to the concept of Potential.

    David Bohm called it "the Implicate", which becomes "Explicated" in reality. I especially like the definitions of Potential as " a latent excellence" and 'that which may become reality".

    This principle would also apply to biology. All events in the universe are preceded by potential. Thus evolution is an expression of potential. "That which became explicate in reality".

    In the case of humans, the accidental fusion of two chromosomes into a single chromosome, created the ability to grow a more complex brain. This in turn can now be interpreted as the turning point in evolution of the mammalian brain, and the ability to communicate increased the human Potential exponentially. The result is self-evident.
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    something to think about. thank you for taking the time.
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