As far as i understand it, the theory of evolution still states that there are random mutations. And through natural selection and survival of the fittest, useful mutations proliferate.
But when I look at nature... I just don't see that many random mutations. Organisms and species seem to be set up to RESIST mutation through things like spontaneous abortion and DNA repair mechanisms and social and sexual aversion to mutations, etc.
And random mutations seem to almost always seem to be bad. To me, it seems that for evolution to have worked through random mutation, there would constantly be tons of horrible mutations in the present and in the fossil record.
It seems to me there must be some kind of biochemical system in organisms and perhaps even in ecosystems that guides mutations.
Kind of like how if the numbers of males and females in a frog population gets wonky, suddenly some of the frogs will start changing sexes. This shows the on some level, their bodies are interacting with the environment with a certain level of cellular intelligence.
I believe this would explain the 'leaps' in evolution we see. And also explain all of the phenomena that religious people chalk up to the invisible man in the sky.
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atheistJon - "To me, it seems that for evolution to have worked through random mutation, there would constantly be tons of horrible mutations in the present and in the fossil record."
atheistJon - "It seems to me there must be some kind of biochemical system in organisms and perhaps even in ecosystems that guides mutations."
Yeah there is, and it is in the title of your thread, "natural selection". Entities with useful mutations flourish and multiply while entities with deadly mutations, well just die and are not heard from again. It would be very strange indeed (and would probably signal the end of the theory) if the fossil record was the way you expect it to be, containing large numbers of entities with deadly mutations.
"But when I look at nature... I just don't see that many random mutations."
Considering I am a person who has monochromacy, and am told I have blue eyes, I would disagree. I have two random mutations just dealing with my eyes.
"Organisms and species seem to be set up to RESIST mutation through things like spontaneous abortion and DNA repair mechanisms and social and sexual aversion to mutations, etc."
Somewhat. Generally these mechanisms work to weed out very detrimental mutations.
"And random mutations seem to almost always seem to be bad."
Every human on earth has around 100 broken genes. The majority of these mutations seem to be in nonessential genes. In cases where the inactivation is common in the population, those tend to be fairly benign traits, like blood type, or people's ability to smell specific substances. The majority of mutations seem to have little if any impact on anything vital.
"To me, it seems that for evolution to have worked through random mutation, there would constantly be tons of horrible mutations in the present and in the fossil record."
If it is as you say, and most of the horrible mutations die fast and before populating, why would you expect to find very many of them in the fossil record. The conditions for fossilization are fairly specific, so it is most likely that most species to ever have existed left few if any fossils.
"It seems to me there must be some kind of biochemical system in organisms and perhaps even in ecosystems that guides mutations."
I am not aware of any specific biochemical systems, but environments provide selective pressure.
"Kind of like how if the numbers of males and females in a frog population gets wonky, suddenly some of the frogs will start changing sexes. This shows the on some level, their bodies are interacting with the environment with a certain level of cellular intelligence."
From what I have read, it seems to have more to do with reproductive strategy. If the balance gets wonky, they aren't able to reproduce, so they change sex to accommodate reproduction.
"I believe this would explain the 'leaps' in evolution we see. And also explain all of the phenomena that religious people chalk up to the invisible man in the sky."
Sounds a bit like punctuated equilibrium.
atheistJon, please read this about Mutations:
http://learn.genetics.utah.edu/content/variation/mutation/
After reading that, you should understand that natural selection is more about filtering the best(luckiest) among the many.
Mutations are constantly happening and they create genetic variation.
But when we are talking about mutation in the macro evolution topic, we are talking about mutation in the genes over a very short period that give a physical (apparent) effect in a way that it classifies as a new specie/branch.
That is rare(if not debatable) and when it happens it is usually is a bad result and dies out.
(eg : disabled people are the result of such mutation)
All observed/studied mutations to this day died out, all failed to reproduce and maintain a continuous structure through generations.
(it is not enough that the mutated genes survive in the gene pool, it has to show up physically in EVERY offspring to be classified as a branch(kind))
Adaptation on the other hand is dealing with natural selection(filtering) of those tiny genetic variation over a very long period of time.
Thus the variations(the few) which are more suitable for the current environment survive, while the others die out faster.(a lot of time is needed for this to happen)
This is the explanation given by natural selection and it explains the evolution of some species.