Extent of Mutational Capability

No problem with your second calculation. It's a good example of genetic entropy.However you started talking about fixed mutations and now you're talking about a gross number of mutations of which only a minority are fixed, so there has been a significant shift in your position during the conversation.

Then I think you don't understand your own argument. Try going back to taws and work through it again. Decide whether you are talking about fixed or unfixed mutations and include time to fixity and reasonable estimates of population size.

Pardon me PaulK, but if you think time to fixity is not relevant when discussing the number of mutations which could become fixed in a certain period then you don't understand what you're talking about.

Are you sure you thought about that response? Let me explain.Say we are looking at a period of 100 generations with 100 mutations expected to be fixed from generation 1.
If the mean time to fixity is 100 generations then we would expect 50 of those mutations to be fixed in the time available.
If the mean time to fixity is 1000 generations then very few, possibly none, of those mutations will be fixed in the time time available.The number of mutations that are expected to be fixed within the time period DEPENDS on the time to fixity.Time to fixity is normally expressed as the Mean Time to Fixity for much the same reasons we measure radioactive decay as a half life.

You're right about mean vs median but apart from that there are no surprises. In round numbers you can say the minimum time to fixity is about Ne and the curve asymptotically approaches the x-axis.There is a similar shaped curve for income distribution with the result that about 60% earn less than the average.As an example then let's say we have a population of Ne=90,000 and a period of 360,000 (4Ne) generations. (About 7.2 million years at 20 years/generation)If each member has ~100 new random mutations then the total number that will eventually reach fixation is 100*360,000=36,000,000.But how many will actually be fixed in that period?Essentially no mutations occurring in the last 90,000 generations will achieve fixation. Of the mutations in the first generation 60% of those that will eventually reach fixation will actually be fixed. A lower proportion will be fixed for each succeeding generation reaching 0% at 270,000 generations. Approximating this as a linear relationship we get
Number fixed=60% * 3/4 * 1/2 ≈ 23%. That is, of the 36 million mutations generated during this period, that are expected to eventually reach fixation, only 23% will actually be fixed by the end of the period.This number will also fall if the population size is larger. For a population size Ne=360,000 almost none of the potentially fixed mutations will actually be fixed within the time period.Immediately after separation of a parent population into two separate species there will of course be a pool of mutations common to both species. Some of these will be fixed in both, and some will be lost in both, so that they will not produce any genetic difference between the species. Some however will be fixed in one OR the other and will then contribute to the genetic difference. How much difference will this make? I don't know and so far none of the respondents has shown they know either. But it's not sufficient to simply assume it will supply any shortfall, or that it will be insignificant.How many new mutations are there for each of us? According to Mutation rate - Wikipedia it is around 64 new mutations per generation, so the figure of 100 used above is an upper bounds estimate.So the original question was whether genetic drift could account for the genetic difference between humans and chimps. I have shown that the simplistic calculation given back at #176 does not stack up.The calculation would have to include realistic mutation rates, population sizes, times to fixation, and pre-loading of mutations from the common ancestral population. All these factors are relevant. Maybe there is a PhD in here for someone.My basic calculations given above suggest to me strongly that genetic drift over ~7 million years would not explain the bulk of genetic differences. Some estimates suggest the last common ancestor was as far back as 13 million years but I don't think even that will salvage the situation. Now I could be wrong, but you'll have to do much better than so far to convince me.However even this does not address the other question of non-homologous genes in each species. In the human Y chromosome 20% have no homologue anywhere in the chimp genome. Overall the figure is about 10%. Similarly chimps have about 10% of their genes that have no homologue in humans.

1. I didn't ignore it and I acknowledged it was greater than zero, however it is unlikely to make up the deficit required. So far you have not shown otherwise.2. There WAS was a bottleneck about 4500 year ago when the human population was reduced to 3 breeding pairs. I did acknowledge the effect on variations in population size, however from the literature you can pick and choose the extent and duration of the bottleneck.3. Your Sandwalk reference makes interesting reading. He acknowledges that MEASURED rates are well below 100 but argues for the higher figure so that the evolutionary story will work.4. Indeed, and I said as much. "... but I don't think even that will salvage the situation. Now I could be wrong, but you'll have to do much better than so far to convince me."I have already responded to your 2nd argument which I have said supports the idea of genetic entropy better than common ancestry.

1. " the vast majority of genes fixed by drift should be variations found in the ancestral population."True, but it doesn't solve the problem. Mutation fixed or lost in BOTH populations will not contribute to differences between the populations. A mutation that is at 50% probability of being fixed has a probability of 25% of being fixed in both, 25% of being lost in both, and 50% of being fixed in one and lost in the other; and this is as good as it gets.A mutation that is at 90% probability of being fixed has a probability of 81% of being fixed in both, 1% of being lost in both, and 18% of being fixed in one and lost in the other, eventually.Actually there is a good chance that many will be neither fixed nor lost within the time available.3. Since when are indirect measurements (estimates) more reliable than direct measurements? Did you really think you could get away with that?4. Since my figures are based on published measurements they are not an intentional underestimate.

The major source for our current Egyptian chronologies are the works of an Egyptian priest called Manetho. They are still the most popular used today, mainly because they are viewed as the most complete and, thus, the best we have. This is despite the fact that both secular and Christian Egyptologists know that these ‘standard’ chronologies are in desperate need of revision.There is good reason to think these greatly exaggerate the duration of the Egyptian civilization.Many other historical events are dated with reference to Egyptian chronology.[edit] Consequently it is likely that the Egyptian civilization was established not long after the flood, probably after the Tower of babel confusion.Edited by CRR, : No reason given.

1. Then do the calculations and prove me wrong.3. Read the article again. The article gives the reason for rejection the directly measured rate.4. No. As I showed it does not support that conclusion."What is Genetic Entropy? It is the genetic degeneration of living things. Genetic entropy is the systematic breakdown of the internal biological information systems that make life alive. Genetic entropy results from genetic mutations, which are typographical errors in the programming of life (life’s instruction manuals). Mutations systematically erode the information that encodes life’s many essential functions. Biological information consists of a large set of specifications, and random mutations systematically scramble these specifications — gradually but relentlessly destroying the programming instructions essential to life." http://www.geneticentropy.org/whats-genetic-entropy