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Evolution of the eye

  1. janesix profile image61
    janesixposted 2 years ago

    Eyes supposedly evolved over millions of years in stages. If mutations are random, how likely is it that each new part "randomly" evolved in the exact spot it needed to be in to make the eye work?

    And for each type of eye, this supposedly happened multiple times independently. That's even MORE unlikely.

    Same goes for birds. How likely is it that the same type of animal just happened to evolve feathers, lightweight bones, wings etc, enabling them to fly? Unlikely.

    How do you explain these things?

    1. Claire Evans profile image88
      Claire Evansposted 2 years ago in reply to this

      It's because it's nonsense.  Let's see how a hawk survives without 20/20 vision.  It would be a disaster. 

      I think the idea of this evolution is more absurd than believing in intelligent design.

    2. wilderness profile image96
      wildernessposted 2 years ago in reply to this

      Start with a flying squirrel (that doesn't actually fly at all).  Gradually turn it into a bat.  Then add a few feathers and tail.  More feathers, lighter bones.  Pretty soon you have a bird.

      Now I know it didn't happen that way, but it might be an indication of how things evolve.

      1. janesix profile image61
        janesixposted 2 years ago in reply to this

        Yes, I get that. What I don't get is how things always evolve right where they need to be. New eye parts evolve where they need to be to enhance vision. You don't see corneas evolving on your liver or your elbow. Where do you see a cornea and a lens evolving? Right where they need to be to make vision possible.

        Same with flight. feathers evolve on animals that eventually evolve into birds, along with hollow bones and wings.

        1. mishpat profile image60
          mishpatposted 2 years ago in reply to this

          Its all a reasoning process on the part of the creature.  For instance, the firefly at one time did not have a "headlight" and kept bumping into trees.  After considering the issue, it decided it would either have to fly during the day or evolve with a headlight.

          1. janesix profile image61
            janesixposted 2 years ago in reply to this

            That's cute, but something is obviously going on that has nothing to do with random mutations. And it's not God, so there has to be something else.

    3. wilderness profile image96
      wildernessposted 2 years ago in reply to this

      Take your "unlikely" and multiply it by millions of years.  Then multiply it again by billions or trillions of gametes each year.  Suddenly it isn't so "unlikely" at all.

      1. janesix profile image61
        janesixposted 2 years ago in reply to this

        Then we should have had plenty of time to evolve corneas on our noses, right?

        Why did corneas evolve independently multiple times, and always on the eye?

        1. wilderness profile image96
          wildernessposted 2 years ago in reply to this

          Who says they DID evolve only on the eye?  Maybe there was a cornea on the nose, that nature found to be counter-productive in the race to reproduce.

          Don't forget that while mutations may be random, the long term results and reproduction of those mutations most definitely is NOT.

          1. janesix profile image61
            janesixposted 2 years ago in reply to this

            Creatures get what they need to adapt to their environment. A bacteria needs to be able to digest sugar, the right mutation happens to make that possible. A bacteria needs to swim faster, it evolves more tails to swim faster. Same for higher animals. It's even predictable, there are studies showing this.

            1. wilderness profile image96
              wildernessposted 2 years ago in reply to this

              No, creatures get whatever the forces of mutation give them.  Ever seen a two headed calf?  A person with but one arm?  Not sure, but think the very first hemophiliac was a queen of England.  Mutations don't care what it is, it just happens.

              Your bacteria may have mutated to have tails in the front.  A bird may mutate back to heavy bones. 

              Whereupon the forces of evolution take over and the bad mutations die out with the positive ones surviving to reproduce.  The bacteria and bird die without ever passing the mutation along, and we never see it.

              1. janesix profile image61
                janesixposted 2 years ago in reply to this

                How are mutations random if they are predictable?

                http://www.nytimes.com/2013/08/15/scien … .html?_r=0

                1. wilderness profile image96
                  wildernessposted 2 years ago in reply to this

                  You will never be able to predict the next mutation (unless you cause it via GMO).  But it is probably possible to predict that sometime in the next million or so gametes one will survive with this or that mutation that is "clearly" beneficial and easy (simple gene change, not complex).  Hard to do, though, considering that every change we make to the environment ends up disastrous.

                  1. janesix profile image61
                    janesixposted 2 years ago in reply to this

                    Why not? 24 times in 24 tries seems pretty predictable to me. Why wouldn't you predict that the 25th try wouldn't have extra tails?

                    edit

    4. Slarty O'Brian profile image87
      Slarty O'Brianposted 2 years ago in reply to this

      Mutation is not random, it's chaotic. The difference being that random can't exist in a cause and effect universe, and chaos is all about order and how the simple quickly becomes the complex.

      1. janesix profile image61
        janesixposted 2 years ago in reply to this

        Thank you for your correction.

      2. janesix profile image61
        janesixposted 2 years ago in reply to this

        I know you're smart. Can you address what I said in the OP and tell me why I'm wrong to think what I think?

        1. Slarty O'Brian profile image87
          Slarty O'Brianposted 2 years ago in reply to this

          Chaos works by simple rules that repeat under changing condition to produce complex systems.
          Weather is a chaotic system we all experience. We can’t predict the weather because it is interconnected with everything going on on the planet. But the weather we get is inevitable because it is based in cause and effect.

          Why do all trees not look the same? Every one is different. Yet trees grow by very simple rules: grow a little, and divide. But how it grows is determined by exactly where it stands and all the conditions it endures. Hence no two trees are exactly alike.

          Atoms follow one basic rule: they must find their lowest possible output of energy. That goal changes all the time due to the interaction of other atoms. Because of this rule atoms are often forced into mergers with other types of atom. When that happens on the atomic level, new substances become present on this level.

          Those substances interact creating new compound substances which interact with others, always gaining in complexity. Each result being inevitable due to every participants nature, as well as that simple first rule that literally effects the behaviour of everything in the universe.

          So rather than being unlikely, the bird and they eye and you and me were inevitable though probably not predictable.

          And who said the ideal spot for eyes is where they are?

          As to dinos, there were plenty of hollow boned ones before there were birds.

          I’m not a biologist and wasn’t there as things evolved, and share your wonder and awe at what nature does. But from a physics stand point I have no problem seeing that the nature of what makes us and everything, is a most amazingly creative force capable of all of this just by flawlessly following very simple rules that are it’s nature.

          There does not seem to be an outside force required.

          Whether there is one or not is anyone’s guess.

          1. janesix profile image61
            janesixposted 2 years ago in reply to this

            "And who said the ideal spot for eyes is where they are?"

            I was saying the ideal spot for eye parts are on the eye.

            Photo receptors develop, then a cup begins to form, then a cornea, lens, etc, all right where they need to be.

            1. mishpat profile image60
              mishpatposted 2 years ago in reply to this

              And don't forget, they are where they can perceive where you're going, not where you've been.  Saves a lot of noggin knots.

        2. mishpat profile image60
          mishpatposted 2 years ago in reply to this

          Ever wonder why there is such a "gap," a series and marked periods of identifiable mutations/evolvements between the creatures of the past and those of today?  Can anyone say that things have changed significantly on Earth in the last 6k years?  Where is the breakpoint the last 6000 years and the previous eons?  It's always "millions of years ago" or in the "jurassic age" and the like or simply "in time past."  We are expected to believe without identifiable proofs, there is a link.  And, yet, each time a new "link" appears on the books, it is quickly defeated by the alternate camp of the same searchers.  And God, well, he doesn't exist, its not His workmanship... but if it is, He certainly screwed things up.

          Lord, what fools these mortals be.

          1. wilderness profile image96
            wildernessposted 2 years ago in reply to this

            Outside of a bunch of extinctions (mostly caused by man), what big changes are you looking at in the last 6000 years?  The ones man domesticated and bred?  Something else?

            1. mishpat profile image60
              mishpatposted 2 years ago in reply to this

              I was kinda looking for some connection between the worlds past, if any, and the present world.  Seems all present history, Biblical and secular, begins about the time of Eden.  There is an huge amount of time between the "verifiable" dinosaurs and the Garden.  Then, of course, there are several unexplained time lapses in our present "world", but mainly what happened in the times between Fred Flintstone and Dino, and the present historical age?

              1. wilderness profile image96
                wildernessposted 2 years ago in reply to this

                Man learned to talk, communicate and write.  He also learned to live in larger groupings, passing along knowledge and history.

                Did I understand your question this time?

                1. mishpat profile image60
                  mishpatposted 2 years ago in reply to this

                  I'm not aware of any reliable sources that indicate "modern" man existed prior to Eden.  There is a lot of guesswork, postulate, etc. that would move man back a couple thousand years, but nothing verifiable.  So it really comes down to who do you believe, or want to believe, regarding the disagreement.  My position is, as usual, the Bible.  It is quite a history book and has been proven correct in many instances, by folks trying to disprove it.  At the same time, these same naysayers have not been able to find error in it, just distain, which is not a proof of anything.

                  1. wilderness profile image96
                    wildernessposted 2 years ago in reply to this

                    Best guess, from scripture, appears to be that Eden was around 8000 years ago.  Man migrated to the Americas long before that and were in Australia 30,000 years before.  Cave art in Europe far predates that, as does the use of tools.  Otzi, in the Alps wasn't much younger, meaning a civilization existed long enough to travel from Africa to there.  Does that count as evidence of modern man?  If not, what were the differences in skeletal or DNA remains?  Or are you merely talking culture, and assuming that the people of Eden had a culture outside of fig leaves?

          2. janesix profile image61
            janesixposted 2 years ago in reply to this

            I really don't know what you're saying.

  2. Cgenaea profile image59
    Cgenaeaposted 2 years ago

    I was told that the Lord created, with his hands, in one day, a living being, with dominion and power to rule over everything here... (stop that eyeball rolling... lol)
    Could one (or two) logically do that without two perfectly working corneas??? The first man mostly blind??? As a Christian, I don't have MUCH critical thinking in my head wink but, maybe I misunderstood something? Eyes which had to evolve?
    What about feet? I hope feet were not developed first and for eons, man actually DID walk by faith alone. wink

    1. janesix profile image61
      janesixposted 2 years ago in reply to this

      Do you actually believe God poofed the first man into existence? I hope you're joking.

      1. Cgenaea profile image59
        Cgenaeaposted 2 years ago in reply to this

        Nope!!! smile ...says he poofed the world into existence. Lol... He took his time to shape, fashion, and form the dude. Poofed him some air...
        I know, I know... somebody somewhere tells a better story. But I believe the bible explanation. The particulars almost really don't matter.
        It's classified info.
        They'll keep guessing until...

 
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