72 replies to this topic

[Mattnxtc]

Ok so I got to thinkin about it and I guess I want to understand it more, I have some thoughts in my head but I want to understand how yall define them to see if my thoughts fit the actual idea...

I am lookin for a complete understanding of this Natural selection process that is the produces evolution. I would like to hear how it works and what its purpose is.

[Petoria]

You might be thinking about it wrong. I wouldnt think about it as having a purpose, I think about it as more just the most likely result.

There is some sort of variance within a population of any species. That basically means, that any two organisms of a species are distinguishable. Now, it's more likely that the organism whose variance is best suited for the environment will survive, maybe not in the short run bc of outside circumstances. Most likely in the long run.

Over time, as this trait gets passed on genetically, this variance will help that organism live on. This means there will be a higher and higher likelihood of seeing the trait. Theoreticallly, the trait should be in every member of the population at a certain time, and this constitutes evolution.

I'm not sure if that answers your question, maybe be a little more specific as to what you're looking for.

[timwakefield]

I have said it before and I'll say it again: "The Blind Watchmaker" by Richard Dawkins is the book you want. Read it, or something similar.


So. Genetic mutations occur at random within any given population. Usually a mutation will cause that specific animal to die, but sometimes it won't. Sometimes the mutation will be a small change which, given that this population has limited resources, will cause that animal to prosper.

Traits are inherited from the parents. Animals which have this beneficial mutation will tend to live longer and have more babies. Their babies will tend to share this new bodily feature with their parent. Those members of the population which have the most helpful mutation will tend to produce the most babies, and over generations this new feature will become common among all members of that population.

But, to take an example, for the giraffe to grow its long neck (assuming that species once had a short neck) would take hundreds of thousands of years at the very least.

Natural selection can't have a purpose any more than the wind can have a purpose. Species aren't TRYING to "improve" or build new bodily features. It just happens.

[Mattnxtc]

You might be thinking about it wrong. I wouldnt think about it as having a purpose, I think about it as more just the most likely result.

There is some sort of variance within a population of any species. That basically means, that any two organisms of a species are distinguishable. Now, it's more likely that the organism whose variance is best suited for the environment will survive, maybe not in the short run bc of outside circumstances. Most likely in the long run.

Over time, as this trait gets passed on genetically, this variance will help that organism live on. This means there will be a higher and higher likelihood of seeing the trait. Theoreticallly, the trait should be in every member of the population at a certain time, and this constitutes evolution.

I'm not sure if that answers your question, maybe be a little more specific as to what you're looking for.

I might be.

Ok so lets clarify something?
We should see a trait that "improves" the organism helping it to live and this will cause evolution?

So is this evolution within the organism (such as adaptation) or does it cause the organism to evolve into a "greater" organism?

I have said it before and I'll say it again: "The Blind Watchmaker" by Richard Dawkins is the book you want. Read it, or something similar.
So. Genetic mutations occur at random within any given population. Usually a mutation will cause that specific animal to die, but sometimes it won't. Sometimes the mutation will be a small change which, given that this population has limited resources, will cause that animal to prosper.

Traits are inherited from the parents. Animals which have this beneficial mutation will tend to live longer and have more babies. Their babies will tend to share this new bodily feature with their parent. Those members of the population which have the most helpful mutation will tend to produce the most babies, and over generations this new feature will become common among all members of that population.

But, to take an example, for the giraffe to grow its long neck (assuming that species once had a short neck) would take hundreds of thousands of years at the very least.

Natural selection can't have a purpose any more than the wind can have a purpose. Species aren't TRYING to "improve" or build new bodily features. It just happens.

so if it doesnt have a purpose does that make it random? Not tryin to argue just tryin to understand your thoughts

[DerekTah]

I like to add in here a little fallicy that I call "perfect adaption fallicy" (maybe it has a more scientific name).

It involves the belief that because the species has survived, the genetic makeup makes up a perfect species for that enviorment. The truth is that there may be flaws in the makeup that the species has survived.

For example in humans the windpipe is one of our great flaws. We are one of the few creatures on the earth that can choke to death on our food. Also our eyes are pretty poor when compaired to other animals (both in distance, and that we have blind spots in our vision).

I bring it up because alot of people at times confuse survival of the fittest, for survival of the most perfect.

[crowTrobot]

so if it doesnt have a purpose does that make it random? Not tryin to argue just tryin to understand your thoughts

1. a random mutation happens. in terms of how a species ability to cope with its environment changes because of the mutation, the mutation is either neutral, detrimental, or beneficial to the individual with the mutation.

2. if the mutation is detrimental to an individual's ability to cope with its environment, it and its offspring (if any) will have a diminished chance of survival and a diminished chance of passing on the mutation.

3. if the mutation is benefical to an individual's ability to cope with its environment, it and its offspring will have an increased chance of survival and a increased chance of passing on the mutation

so within a species, environmental pressure tends to weed out detrimental mutations and allow benefical ones to thrive. this is the simple version of course. there is a lot more complexity involved - environmental pressures for a given species are frequently changing, mutation rates probably vary, sizes of interbreeding populations of species are critical, etc.

[timwakefield]

I like to add in here a little fallicy that I call "perfect adaption fallicy" (maybe it has a more scientific name).

It involves the belief that because the species has survived, the genetic makeup makes up a perfect species for that enviorment. The truth is that there may be flaws in the makeup that the species has survived.

For example in humans the windpipe is one of our great flaws. We are one of the few creatures on the earth that can choke to death on our food. Also our eyes are pretty poor when compaired to other animals (both in distance, and that we have blind spots in our vision).

I bring it up because alot of people at times confuse survival of the fittest, for survival of the most perfect.

Yes and this is one of the stronger arguments against a Creator god. Why would he have made things so clumsily?

[timwakefield]

so if it doesnt have a purpose does that make it random? Not tryin to argue just tryin to understand your thoughts

Here's a fairly poor analogy, but it gets the point across: it's random as much as poker is random. The cards fall at random, but the game as a whole is not a random process. Likewise, mutations occur at random (or by God's hand, if you like) but the process by which animals evolve is quite the opposite of random; evolution occurs because animals DON'T just live and die at random....those more suited to their environments live longer, have more babies, and pass their traits down to those babies.

[Petoria]

Something that hasnt been mentioned, is if this beneficial trait should spread throughout the population of an organism, then why do we observe so many species on earth?

Is it mostly geographical? If there is someone who is more knowledgeable on the subject, I've always wondered.

[DerekTah]

Yes and this is one of the stronger arguments against a Creator god. Why would he have made things so clumsily?

That is sort an opinion though, I mean for all we know god is like "I don't want that group to eat with such big bites, looks gross. I know the windpipe"

Remember its us who see the idea of something being made "with percision" or "clumsily" is in our eyes.

Using a better example, the lemming clearly has a flaw that when it disperse it will at times basicly commit suicide in the process. That flaw has probably in the end help the lemmings more than hurt them because they don't overpopulate an area.

[Petoria]

That is sort an opinion though, I mean for all we know god is like "I don't want that group to eat with such big bites, looks gross. I know the windpipe"

Remember its us who see the idea of something being made "with percision" or "clumsily" is in our eyes.

LOLOLOLOLOLOLOL, OMG that's the funniest thing I've heard in a while.

Didn't God make us in his image, and isn't he perfect? God doesnt eat big bites? Sounds like kind of a ridiculous claim to make, but whatever. You're trying to back peddle a bit, I'm amused though.

[DerekTah]

I'm not backpeddling and you do know it was basicly a joke.

Look I do not believe in ID theory. My problem with it is the old "the glasses fit our nose, therefore the nose is perfect" part that typically comes out somewhere.

To say "look this bit of us is perfect, therefore clearly designed" is wrong.

Also "look this bit of us doesn't work quite right, therefore no god" is also wrong.

[timwakefield]

Is it mostly geographical? If there is someone who is more knowledgeable on the subject, I've always wondered.

It is entirely geographical/environmental.

[timwakefield]

Remember its us who see the idea of something being made "with percision" or "clumsily" is in our eyes.

In some cases, yes. In other cases, no. There are numerous examples of traits within a species which are either not beneficial in any observed way, or which are extremely roundabout or overly complicated.

Using a better example, the lemming clearly has a flaw that when it disperse it will at times basicly commit suicide in the process. That flaw has probably in the end help the lemmings more than hurt them because they don't overpopulate an area.

I don't know anything about lemmings, but I think it is more likely that their species has continued to survive IN SPITE of this ridiculous suicidal activity. This would be an example of "clumsy evolution."


On the flip side, if in fact lemmings somehow evolved in such a way that a random selection of the population jumps off a cliff, and the rest of the population as a result has enough food etc for everybody, then that would also be an example of "clumsy evolution." What sort of twisted Creator would cause a species to have an unending overpopulation problem, and solve it by having the excess animals kill themselves, by acccident, all at once?

Also "look this bit of us doesn't work quite right, therefore no god" is also wrong.

I didn't mean to say ..."therefore no god." That's unprovable. What I should have said was that this clumsiness, which can be observed in any variety of species curently existing, is more proof of evolution.

Natural selection is not process which necessarily creates animals which are perfectly suited to their environment (or to anything), and the resulting imperfections are clearly visible.

[crowTrobot]

Using a better example, the lemming clearly has a flaw that when it disperse it will at times basicly commit suicide in the process.

lol the suicide thing is a total myth. the lemming population varies in large cycles because they have the benefical (for the population) genetic trait of expending less energy on breeding when less food is available (kinda the opposite of humans..). natural selection can work both on individuals and populations.

[DerekTah]

lol the suicide thing is a total myth. the lemming population varies in large cycles because they have the benefical (for the population) genetic trait of expending less energy on breeding when less food is available (kinda the opposite of humans..). natural selection can work both on individuals and populations.

No the suicide thing is true, I'm not talking about them jumping off cliffs.

From wikipedia: In fact, the behavior of lemmings is much the same as that of many other rodents which have periodic population booms and then disperse in all directions, seeking the food and shelter that their natural habitat cannot provide. (The Australian Long-haired Rat is one example.) The actual reason for their 'suicide' deaths is because these mass migrations may last many months and the lemmings become too tired to avoid cliff edges or swim when they normally could.

Granted I probably should of said "cause them to die" and not "commit suicide". But the point is that they do die out because of the way they disperse, but that it does help the lemming in the end.

Oh, Tim I understand the point, I'm just saying the one can always argue the "god wanted it that way" of design, so mentioning the perfection/clumsiness of design becomes mute when agruing for/against creation.

[timwakefield]

Granted I probably should of said "cause them to die" and not "commit suicide". But the point is that they do die out because of the way they disperse, but that it does help the lemming in the end.

It DOESN'T necessarily help the lemmings as a species in the end.

Oh, Tim I understand the point, I'm just saying the one can always argue the "god wanted it that way" of design, so mentioning the perfection/clumsiness of design becomes mute when agruing for/against creation.

By those standards, it is totally impossible to ever argue against creationism. I will concede that this point doesn't necessarily negate creationism, but it does give further proof of evolution.

[DerekTah]

It DOESN'T necessarily help the lemmings as a species in the end.
By those standards, it is totally impossible to ever argue against creationism. I will concede that this point doesn't necessarily negate creationism, but it does give further proof of evolution.

Ok, granted. I guess I'm in a devil advocate mood today or something.

[Mattnxtc]

so according to evolution

if there is a "detrimental evolution" should we expect that species to survive? and for how long?

Also for a species that "naturally evolves" are they staying as the same species or are they evolving into another species?

[LongLiveYorke]

so according to evolution

if there is a "detrimental evolution" should we expect that species to survive? and for how long?

Your question is better stated as a "detrimental mutation." Evolution is a term that describes the overall process which combines mutations and concept of "survival of the fittest." So, to answer your question, yes, of course there can be detrimental mutations. The survival of an individual with one of these "bad" mutations depends on how "bad" the mutation is and the extent to which it would in inhibit the survival of the individual. Of course, if the mutation is minor enough, it may remain within a species as a totally unnecessary trait. So, to answer your question, it depends.

Also for a species that "naturally evolves" are they staying as the same species or are they evolving into another species?

Don't think as a "species" as such a discrete thing. There is no line that a species will cross when it becomes another species. It will gradually evolve and change and, looking back after millions of years, one can declare that it has become a new "species," but really it is a gradual and continuous process.