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Old 11th April 2008, 01:24 PM   #12
Dancing David
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Join Date: Mar 2003
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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?


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.
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.
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.
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.
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.
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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And a shot rang out. Now Space is doing time... -Ben Burch
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Last edited by Dancing David; 11th April 2008 at 01:26 PM.
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