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Random mutations cannot explain evolution of humans

wogoga

Critical Thinker
W
Joined
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334
The question at issue is not whether gradual transitions are conceivable (and existent), but whether they can be explained by the assumption that they are caused by random mutations.

Take the case of humans after their separation from chimps some million years ago. An upper limit to the number of individuals having been born since then is 10^16 (i.e. 10^9 newborns per year for 10^7 years).

10^16 is an extremely small number when compared with the number of possible mutations in the genetic code. Let us assume that the number of relevant base pairs (i.e. without junk DNA) is 100'000'000 pairs per chromosome set. This results in three hundred million possible point-replacement mutations (because every base pair can be replaced by three alternatives).

The number of possible combinations of two such point mutations is already 10^17, i.e. higher than the number of all "humans" ever born since our separation from chimps. The number of all possible single-step mutations is even much higher than the number of point-replacement mutations.

So evolutionary advantages depending on two or more single-step mutations cannot have had a relevant impact (at least for human evolution). If we believe in neo-Darwinism we must assume that every innovation is produced by a sequence of single-step mutations, each of which alone responsible for a relevant increase in fitness.

Let us assume that three factors must be affected for an increase in fitness to emerge. So even if the probability of a beneficial mutation in a newborn were as high as 10^-5 for each factor, the probability that beneficial mutations occur for all three factors is 10^-15, i.e. extremely improbable.

So neo-Darwinism requires essentially this hypothesis:

Every evolutionary innovation can produced by a sequence of single-step mutations, each of which alone responsible for a relevant increase in fitness.​

Because this hypothesis is obviously wrong, neo-Darwinism is refuted.

If we take into account that many properties depending each on more than one single genetic factor must evolve at the same time, it becomes even more obvious that the neo-Darwinian explanation of evolution is simply untenable.

The upright gait was only one of many traits which had to evolve in us after our separation from chimps. For that to happen, the structures of bones, of muscles and of tendons had to gradually change. Let us ignore that in fact the bone structure (involved in the upright-gait evolution) alone consists of several bones with each several traits.

So let us make the completely unrealistic assumption that one 'progressive' single-step mutation in the genetic factor of each (i.e. bone, muscle and tendon) structure is enough to entail a relevant increase in fitness.

Let us further assume that the probability of such progressive mutations in newborns is each as high as 10^-5. So we conclude that among 10^15 newborns (i.e. a billion newborns of a million generations), only one individual will carry all three necessary mutations.

Because a change in only one or two of the three involved structures cannot lead to a relevant increase in fitness (rather the contrary), it becomes obvious that the upright gait cannot have evolved in a neo-Darwinian way.

Cheeers, Wolfgang

The above is a composition of extracts from posts to talk.origins from November 2000
 
wogoga said:
The question at issue is not whether gradual transitions are conceivable (and existent), but whether they can be explained by the assumption that they are caused by random mutations.
Click to expand...


Nope. Random mutations + selection.
 
Actually, no. The upright gait was present before the split with chimps for one thing, and even an obligatory quadroped can manage an upright gait (see http://www.youtube.com/watch?v=01vp5ivt3d4).

People make these sorts of arguments about probability all the time, and it usually reveals a lack of understanding. It's not "one mutation = one change in one part of the anatomy".
 
Are you trying to cause trouble, wogoga?

1st The soul juice thread
2nd The "Dawkins favorite homosexual" thread
3rd Now this, after a huge awful thread on this topic just died down, like 1 day ago.

Wogoga, why didn't you contribute to that thread?

Also, I'm waiting for your response to my spaghetti monster theory of demographics. If you don't answer soon the spaghetti monster might eat all your soul juice! :jaw-dropp
 
wogoga said:
If we believe in neo-Darwinism we must assume that every innovation is produced by a sequence of single-step mutations, each of which alone responsible for a relevant increase in fitness.
Click to expand...


Poor assumptions lead to bad conclusions and this is just absurdly wrong.
 
Mangling probability won't convince anyone you would have missed if you had simply left the "probability" out of your story.

Except that it will, and that makes me sad. :(
 
wogoga said:
Because a change in only one or two of the three involved structures cannot lead to a relevant increase in fitness (rather the contrary), it becomes obvious that the upright gait cannot have evolved in a neo-Darwinian way.

Cheeers, Wolfgang
Click to expand...

hmmm...

Gorilla.jpg

From Here
 
This ties in (nicely) with KingMerv00's thread about overcoming confirmation bias. I think wasting time addressing some of the lamer arguments against Evolution Through Natural Selection, such as the one presented in the OP, goes a long way toward giving us the impression that they are all lame. Admitedly this impression has yet to be disconfirmed, but still....

Linda
 
uM, an argument from incredulity that uses a posetiori statistics is not much of an arguemnt



Is the trait for upright gait possible in the critter that led to bot humans and chims?

yes.

It could either be gradual or drastic as far as joint and bone changes to encourage upright posture. The main trairt that makes an ape different from a monkey is that apes hang from branches (braciations) and monkeys walk an top. So you can have the development of upright gait from already existing potential through gradual shifting or drastic shifting, as long as there is a reason that it doesn't harm reproduction and it improves reproduction.

that is all it takes.

Then you have the usuall strawman logic
So evolutionary advantages depending on two or more single-step mutations cannot have had a relevant impact (at least for human evolution). If we believe in neo-Darwinism we must assume that every innovation is produced by a sequence of single-step mutations, each of which alone responsible for a relevant increase in fitness.
Click to expand...
Np you do not have to have mutation at all, just bariability in the expression of the genome, some people have very tight ligaments, some have very loose ligaments and some people have a range in between. Just like skin tone, so you have variation in the expression of traits in the genome.

And guess what you can have natural selection from just that, no need for mutation at all, take white foxes and black squirrels, they are not like albinos there are expresses double reccesive (white fox) and double dominant (black squirell) of existing traits. Variation in expression of traits is enough for natural selection to occur.

Ah, a posteriori statistics

Let us assume that three factors must be affected for an increase in fitness to emerge. So even if the probability of a beneficial mutation in a newborn were as high as 10^-5 for each factor, the probability that beneficial mutations occur for all three factors is 10^-15, i.e. extremely improbable.
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First off you need variation in the expression of traits not mutations. Secondly this is like saying that a straight royal flush of hearts is impossible. Well it isn't. This is like saying that the density of people in the Netherlands is 20/KM, and so it would be impossible for a city to arise.

here is more straw to throw on your fire
Every evolutionary innovation can produced by a sequence of single-step mutations, each of which alone responsible for a relevant increase in fitness.
Click to expand...

That is not at all what neo darwinism is, which is a foolish dodge to avoid saying the theory of natural selection through reproductive success.

You have variation in expression of traits, you do also have random changes in the genome for a huge variety of reasons, most mutations will be neutral to the repoduction of the individual. It is only when the trait impacts reproduction that it will be selected for or against.

Nuetral traits may remian un-impactfull until there is a change in the enviroment.

The upright gait was only one of many traits which had to evolve in us after our separation from chimps. For that to happen, the structures of bones, of muscles and of tendons had to gradually change. Let us ignore that in fact the bone structure (involved in the upright-gait evolution) alone consists of several bones with each several traits.
Click to expand...
Okay, right i forgot all members of the species are exactly the same like little robots, geesh, how could I have missed that.

I mean really the fact that some have longer legs than others is just impossible! Or that animals have variations in the amount of bend in thier joints is just preposterous, and quite impossible, every creature in a species is exactly like every other.


then there is your further incorrect use of statistics:
Let us further assume that the probability of such progressive mutations in newborns is each as high as 10^-5. So we conclude that among 10^15 newborns (i.e. a billion newborns of a million generations), only one individual will carry all three necessary mutations.
Click to expand...

Now lets look at the truth, in any trait that is expressed in development can have variation, now some traits have greater variation than others say 35% to 1%. And then we just give an organism ten traits that they can express, and to make it easy each trait only has five variations, how many combinations and permutations is that?

Sorry my brain is not working so I will just pull numbers out of the air!

nCr=n!/(r!(n-r)!) is that what, my brain is tired.

It could also be that it is 510

So lets say that the combinations are a big number 1000 and that the combinations we want are a value of -1- for variable *1 and *2 to have a tendency towards an upright gait. So the combiantions that we want are like 40 out of 1000, so what are the chances of 40/1000 expressed over 10,000 individuals? 400?

So out of ten thousand individuals 400 of them will find it easier to have an upright gait?

(Something like that, gosh i love it when the weather gets nice and the tree bloom, the day is sunny but my allergies have me all fogged up.)

It is probably more like 40/10000 any way, I can tell you in a few days. Or 210
So with either 4, 40, 400 individuals with the tendency to an upright gait, the natural selection happens if there is a reproductive benefit to the upright gait.

Even with just 4 individuals in the population with a small increase in reproduction you will eventually have a population that expresses the trait more than not.
 
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Your numbers are wildly wrong. I'll do them correctly for you.

The human genome differs from the chimpanzee genome by only 35 million base pairs, of which about 5 million are thought to be active. Compare that to the total genome of around 3 billion base pairs.

So disregarding the inactive mutations, there needs to have been time for about 5 10^6 beneficial point mutations to take place. That's all.

The rate of point mutations is roughly 100 per birth. After a few hundred generations, any beneficial mutation will spread throughout the genome. So if it has been 5 10^6 years = 2 10^5 generations since humans and chimps diverged, 2 10^5 * 100 * N mutations have occurred, where N is the population size (taken to be constant for simplicity). You took N = 10^9, which is obviously too high - let's take it to be 10^7. Then we have a total of 2*10^14 mutations total in the human genome since the time we diverged from chimps.

Of those, 5 10^6 active ones remain. So in order to explain the divergence we need that the rate of beneficial mutations in humans/chimps be around 1 in ten million. That is very low, but it might be about right.

This may also allow us to estimate the rate of neutral (inactive) mutations - naively very roughly 1 in a million (all the rest being harmful). However the logic applied to neutral mutations is a bit slippery.
 
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Human beings are sentient and actively aid evolution. According to Darwin, this was a part of the reason for racial features. People activel chose those that they thought were desirable in their culture. People could also better judge what people were healthy and successful.
 
I am sort of thinking for now, I can be very wrong, but I think that the formulat i was to use is rPn=n!/(n-r)!

So then a set of ten places with five values is 10!/5! or 10x9x8x7x6=30,240

and if we say that to have an easier time with upright giat that there has to be a value of -1- in places *1 and *2 (the first two) then that set is 8!/5!=8x7x6=336


so the ratio is a lot lower than in my made up numbers 336/30240 but the effect is still the same because if you have 112 out of 10,080 that is still a significant portion of the population for natural slelction to imapct.

And then there is the whole issue of "the genetic information came from 10,000" individuals, now this does not mean that there were only ten thousand humans at some point, what this does mean , is that out of an unknown population there were at some point ten thousand who ultimately went on to contribute to the gene pool, you can have millions and millions of potential contributors in some sets, as long as only ten thousand eventualy have survivors in the gene pool.

It does not mean that the human race started with ten thousan proto humans!
 
In another thread I was informed that Adam and Eve were the most perfect specimens of humans, ever, considering where they came from! :)
I guess that perfection didn't get passed down to their descendants in the 6000 years since.
 
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