Freethought & Rationalism Archive

Amaleq13 · 06-19-2007, 10:58 AM

Quote:

Originally Posted by afdave

Also note that the work of leading modern population geneticists implies that the farther back in time we go, the more free of deleterious mutations is the human race. J.F. Crow (1997) was explicit about this.

Please provide a specific reference for this, if not the actual quote (surrounding context would be great to avoid charges of quote mining) upon which you are relying for this claim.

Dean Anderson · 06-19-2007, 11:03 AM

Quote:

Originally Posted by afdave

Pappy Jack ... if you disparage the integrity of my sources, I would ask that you support your disparagement. Smyth's measurements were in fact vindicated by Davidson, whose work I am examining now. At RD.net, you claimed that Smyth had been discredited by Petrie, but you did not even mention Davidson. Why not? Have you read Davidson? Now it is fine with me if you do read Davidson, find some flaws, and then dismiss Smyth on the basis of these flaws, but until you do that, you have no basis for criticising Smyth. Remember ... Petrie himself was fully convinced of Smyth's work and only rejected parts of it ... and those, only because he failed to account for the "hollowing in" effect, which Davidson later accounted for.

And let me reiterate ... I have NO interest in Davidson's prophetic inferences ... only his measurements and his reconciliation of Smyth's and Petrie's work.

I am very familiar with both Smyth's figures and Petries figures.

Please show me Davidson's calculations that "reconcile" the two, so that I can assess them.

It sounds like these calculations are the same ones that Peter LeMesurier uses in "Decoding the Great Pyramid" (in fact I would not be surprised if Davidson's book directly references LeMesurier, particularly given your mention of "hollowing in"). If so, then they are completely bogus finagling of the numbers.

Smyth's figures cannot be reconciled with those of Petrie in the way that LeMesurier claims. It is a geometrical impossibility. Smyth's figures are just wrong, plain and simple, and LeMesurier is either incompetent or a fraud.

So let's see Davidson's calculations, then...

Dave Hawkins · 06-19-2007, 12:06 PM

It will take me more time to provide Davidson's data for you, but the Crow quote I can provide easily ... This is from the very end of the paper (free acess) ...

Quote:

The Current Human Population

However efficient natural selection was in eliminating harmful mutations in the past, it is no longer so in much of the world. In the wealthy nations, natural selection for differential mortality is greatly reduced. A newborn infant now has a large probability of surviving past the reproducing years. There are fertility differences, to be sure, but they are clearly not distributed in such a way as to eliminate mutations efficiently. Except for pre-natal mortality, natural selection for effective mutation removal has been greatly reduced.

It seems clear that for the past few centuries harmful mutations have been accumulating. Why don't we notice this? If we are like Drosophila, the decrease in viability from mutation accumulation is some 1 or 2% per generation. This is more than compensated for by much more rapid environmental improvements, which are keeping well ahead of any decreased efficiency of selection. How long can we keep this up? Perhaps for a long time, but only if there remains a social order that permits steady environmental improvements. If war or famine force our descendants to return to a stone-age life they will have to contend with all the problems that their stone-age ancestors had plus mutations that have accumulated in the meantime.

We have seen that quasi-truncation selection can efficiently remove harmful mutations, and the average fitness reduction can be made quite small. This, plus environmental improvements, means that average survival and fertility are only slightly impaired by mutation. Yet, those 80 mutations in a fly---and whatever the number is in the human species---must surely have deleterious effects that don't show up in a life table (or as effects on fitness). How many headaches, stomach upsets, depressed periods, and such things that make life less pleasant, but don't reduce viability or fertility, would be eliminated if our mutation rate had been lower? I suspect the number is substantial.

If the human mutation rate were to drop to zero, we would probably not notice it except for the absence of some of the most loathsome dominant diseases. Loss of variability would not be a problem for a very long time. The genetic variance in the population is enough to satisfy the dreams of even the most wild-eyed eugenist. If we could reduce the mutation rate to zero (without important side effects, of course) I would be for it. If some centuries in the future new mutations are needed, we shall certainly know how to produce them.

I do regard mutation accumulation as a problem. It is something like the population bomb, but it has a much longer fuse. We can expect molecular techniques to increase greatly the chance of early detection of mutations with large effects. But there is less reason for optimism about the ability to deal with the much more numerous mutations with very mild effects. But this is a problem with a long time scale; the characteristic time is some 50-100 generations, which cautions us against advocating any precipitate action. We can take time to learn more.

Meanwhile, we have more immediate problems: global warming, loss of habitat, water depletion, food shortages, war, terrorism, and especially increase of the world population. If we don't somehow reduce the global birth rate to a sustainable level commensurate with economic viability, we won't have the luxury of worrying about the mutation problem.
http://www.pnas.org/cgi/content/full/94/16/8380

Note that Crow implies that our Stone Age ancestors had LESS of a load of deleterious mutations than we do. Farther back in time = fewer deleterious mutations. This picture of less harmful mutations further back in time correlates well with Biblical inferences.

Dean Anderson · 06-19-2007, 12:26 PM

Quote:

Originally Posted by afdave

It will take me more time to provide Davidson's data for you, but the Crow quote I can provide easily ... This is from the very end of the paper (free acess) ...

Quote:

The Current Human Population

However efficient natural selection was in eliminating harmful mutations in the past, it is no longer so in much of the world. In the wealthy nations, natural selection for differential mortality is greatly reduced. A newborn infant now has a large probability of surviving past the reproducing years. There are fertility differences, to be sure, but they are clearly not distributed in such a way as to eliminate mutations efficiently. Except for pre-natal mortality, natural selection for effective mutation removal has been greatly reduced.

It seems clear that for the past few centuries harmful mutations have been accumulating. Why don't we notice this? If we are like Drosophila, the decrease in viability from mutation accumulation is some 1 or 2% per generation. This is more than compensated for by much more rapid environmental improvements, which are keeping well ahead of any decreased efficiency of selection. How long can we keep this up? Perhaps for a long time, but only if there remains a social order that permits steady environmental improvements. If war or famine force our descendants to return to a stone-age life they will have to contend with all the problems that their stone-age ancestors had plus mutations that have accumulated in the meantime.

We have seen that quasi-truncation selection can efficiently remove harmful mutations, and the average fitness reduction can be made quite small. This, plus environmental improvements, means that average survival and fertility are only slightly impaired by mutation. Yet, those 80 mutations in a fly---and whatever the number is in the human species---must surely have deleterious effects that don't show up in a life table (or as effects on fitness). How many headaches, stomach upsets, depressed periods, and such things that make life less pleasant, but don't reduce viability or fertility, would be eliminated if our mutation rate had been lower? I suspect the number is substantial.

If the human mutation rate were to drop to zero, we would probably not notice it except for the absence of some of the most loathsome dominant diseases. Loss of variability would not be a problem for a very long time. The genetic variance in the population is enough to satisfy the dreams of even the most wild-eyed eugenist. If we could reduce the mutation rate to zero (without important side effects, of course) I would be for it. If some centuries in the future new mutations are needed, we shall certainly know how to produce them.

I do regard mutation accumulation as a problem. It is something like the population bomb, but it has a much longer fuse. We can expect molecular techniques to increase greatly the chance of early detection of mutations with large effects. But there is less reason for optimism about the ability to deal with the much more numerous mutations with very mild effects. But this is a problem with a long time scale; the characteristic time is some 50-100 generations, which cautions us against advocating any precipitate action. We can take time to learn more.

Meanwhile, we have more immediate problems: global warming, loss of habitat, water depletion, food shortages, war, terrorism, and especially increase of the world population. If we don't somehow reduce the global birth rate to a sustainable level commensurate with economic viability, we won't have the luxury of worrying about the mutation problem.
http://www.pnas.org/cgi/content/full/94/16/8380

Note that Crow implies that our Stone Age ancestors had LESS of a load of deleterious mutations than we do. Farther back in time = fewer deleterious mutations. This picture of less harmful mutations further back in time correlates well with Biblical inferences.

He implies nothing of the sort.

His intended meaning is rather different, as the rest of his paper clarifies.

He points out that - like Drosophila (or any other organism), we tend to accumulate harmful mutations at a steady rate over time. (He also discusses whether average paternal age has any effect on this).

His point is not that our ancestors acquired fewer harmful mutations and therefore would have been stronger and longer-lived than us. His point is the very opposite.

Our ancestors acquired the same number of harmful mutations as us, and at the same rate; but we can cope with these mutations better than they can. Therefore, whereas our ancestors would have been heavily affected by some of these mutations - to the point of living short lives and not surviving to breeding age - we (with our modern society and medical technology) can survive with them for far longer and can breed whilst having them.

Therefore, they are no longer being weeded out like they used to be, and they are accumulating in the gene pool.

This is the very opposite of what you claim that he implies. You are claiming that he implies that our ancestors were stronger and longer lived than us and (particularly for your 600 year argument) more fertile "which correlates with Biblical inferences". He is actually saying that our ancestors were more susceptible to harmful mutations than we are and therefore they lived shorter lives and more of them died without having chance to have children.

Dean Anderson · 06-19-2007, 12:37 PM

Quote:

Originally Posted by afdave

As for your Flood date, I will examine your link. My first thought is that it seems quite possible that genealogical tables might not include every person in the line. I am not in a position to support that notion firmly, but I think I could be if I took the time.

I realise I've already responded to this post, but something very fundamental has struck me about this small passage.

If I were writing that, I would have written something along the lines of...

My first thought is that it seems quite possible that genealogical tables might not include every person in the line. I'll examine this in more detail and see if that is indeed the case.

In other words, after having thought of something that may invalidate the claim (in this case, as I have already pointed out, it wouldn't - but that's not the point) I would examine the claim in more detail to see if my idea appeared to be correct or not.

Dave's wording is quite different to this, though. He says "I am not in a position to support that notion firmly, but I think I could be if I took the time."

In other words, there is no hint of "I don't know if my idea is right or not, so I'll look at the evidence and see if my idea is supported by it" in his post. Instead, it says (to paraphrase) "I presuppose that my idea is right, and I'll look for some evidence to support my idea."

I think this is an excellent example of the fundamental difference between proper science and scholarship and apologetics.

Scholarship says: Here's the evidence. What conclusion should I draw from it?

Apologetics says: Here's my conclusion. What evidence can I find to support it?

Pappy Jack · 06-19-2007, 12:45 PM

Quote:

Originally Posted by afdave

Pappy Jack ... if you disparage the integrity of my sources, I would ask that you support your disparagement.........

Dave,

Thanks for delimiting the circumstances under which I can take issue with your sources.

Smyth and Davidson can support each other’s measurements as much as they like, but the fault lies not in the measurements (of doubtful accuracy as they may be), but in the absurd conclusions drawn from them. To cite but one example, Smyth’s sacred cubit (from which he calculated the pyramid inch from which all else is derived) is based on the width of but one casing stone which was available for him to measure; subsequent excavations produced casing stones with different widths. Furthermore, even archaeologists of Smyth’s day disagreed on almost every Great Pyramid measurement and later archaeologists produced even more different measurements. To put it simply, it is almost impossible to measure a structure as large, ancient and weathered as the Great Pyramid and produce measurements which precisely enumerate its dimensions when it was first constructed.

I draw your attention to two comments by Martin Gardner from the reference I gave you previously:

Quote:

Our Inheritance [in the Great Pyramid] is a classic of its kind. Few books illustrate so beautifully the ease with which an intelligent man, passionately convinced of a theory, can manipulate his subject matter in such a way as to make it conform to previously held opinions.

Quote:

It is not difficult to understand how Smyth achieved these astonishing scientific and historical correspondences. If you set about measuring a complicated structure like the Pyramid, you will quickly have on hand a great abundance of lengths to play with. If you have sufficient patience to juggle them about in various ways, you are certain to come out with many figures which coincide with important historical dates or figures in the sciences. Since you are bound by no rules, it would be odd indeed if this search for Pyramid "truths" failed to meet with considerable success.

Both quotations from:

The Great Pyramid, Chapter 13 of FADS & FALLACIES, In the name of science. Martin Gardner. Dover Publications, NY, 1957, p. 173-185

which can be found here:

http://skeptically.org/skepticism/id15.html

You really should look at this if you haven’t already. To further illustrate the utter futility of Smyth’s mathematical manipulations, Gardner uses publicly available measurement data about the Washington Monument to ‘prove’ hidden cosmological knowledge (the speed of light) and numerical secrets (the importance of the value '5') contained in its measurements, Did the architects of the Monument deliberately incorporate these concealed values? By Smyth's logic, they must have.

Dean Anderson · 06-19-2007, 01:17 PM

Quote:

Originally Posted by Pappy Jack

To cite but one example, Smyth’s sacred cubit (from which he calculated the pyramid inch from which all else is derived) is based on the width of but one casing stone which was available for him to measure; subsequent excavations produced casing stones with different widths.

Not only that, but the specific casing stone in question that Smyth claims to have measured accurately (or more specifically, the "boss" on it) is nothing like the size that Smyth claims it to be.

Smyth's "5 sacred inch x 5 sacred inch" boss is actually not even square. Its length varies from 4.7 to 5.2 inches, and its width varies from 3.3 to 3.5 inches.

Amaleq13 · 06-19-2007, 01:24 PM

Quote:

Originally Posted by afdave

Note that Crow implies that our Stone Age ancestors had LESS of a load of deleterious mutations than we do.

He clearly argues that unimpeded natural selection results in fewer deleterious mutations being reproduced. IOW, our Stone Age ancestors, lacking the modern ability to impede natural selection, had more people with deleterious mutations die before reproducing.

If that is what you mean, yes. If you mean that he claims our ancestors had somehow superior DNA to ours, no. That would be an incorrect reading of his words.

Quote:

Farther back in time = fewer deleterious mutations.

Farther back in time = fewer reproducing deleterious mutations.

Quote:

This picture of less harmful mutations further back in time correlates well with Biblical inferences.

Does the fact that human interference with natural selection has, within "the past few centuries", resulted in greater numbers of deleterious mutations surviving to reproduce correlate well with your "Biblical inferences"? Because that is what Crow is stating. He was most clearly not claiming that our ancestor's DNA was more free of deleterious mutations but claiming that more of them died before reproducing.

Pappy Jack · 06-20-2007, 05:36 AM

Quote:

Originally Posted by Dean Anderson

Quote:

Originally Posted by Pappy Jack

To cite but one example.......

Not only that, but the specific casing stone in question that Smyth claims to have measured accurately (or more specifically, the "boss" on it) is nothing like the size that Smyth claims it to be.

Smyth's "5 sacred inch x 5 sacred inch" boss is actually not even square. Its length varies from 4.7 to 5.2 inches, and its width varies from 3.3 to 3.5 inches.

Thanks for that, Dean. And let's not forget that Flinders Petrie reported catching a Smyth-supporter actually filing down the boss to more nearly match the required dimensions to support Smyth's ideas.

Dave Hawkins · 06-20-2007, 10:41 AM

This diagram is from Davidson, D., The Great Pyramid, 4th ed., London, 1927, Plate XVII.

Hi Dean-- You appear to be very knowledgeable about Petrie's work at the Pyramid so I am curious to hear what you have to say about Davidson's analysis of Petrie's work. As I said earlier, I have no interest in Davidson's prophetic inferences ... only his analysis of Petrie's and Smyth's measurements. I want to know if the GP embodied advanced scientific knowledge or not, and it appears with what I know now that it did indeed. But I am happy to be corrected on this if I can be shown that it is wrong.

Davidson's reconstruction is in Fig. A on the left and shows the casing following the hollowed-in effect. This would vindicate Prof. Smyth if true. Is it true or not? Well ... it seems logical that the casing stones would follow the core, does it not? Davidson makes a case, but it is spread throughout his large volume in various places, so it will take me some time to work through it. One item he offers is that it appears Petrie assumed the casing stones would sit IN the sockets instead of OVER the sockets. Regarding this, Davidson says (p. 121)

Quote:

The discovery of the Lisht Pyramid sockets and their foundation deposits (refer Section III, para 197a) may have caused Professor Petrie to modify his reconstruction in this detail. But even this modification could scarcely redeem the evident weakness of his reconstruction as applied to the South-East socket corner casing stone.

I have not yet found what Davidson is referring to in that last sentence, but regarding the Lisht Pyramid, Davidson reports Dr. Albert Lithgoe as saying ...

Quote:

The pocket had then been completely filled with gravel, on which, at about half its depth, was laid a small model brick of sun-dried Nile mud. Finally, the pockets were covered by massive limestone blocks, which in each case formed the corner blocks of the Pyramid platform. (p. 175)

So it appears that Davidson's theory of the casing stones has support from the Lisht Pyramid.

Again, I am very open-minded on this and would love to hear your take. Also, I don't know much about LeMesurier. I think he wrote long after Davidson.

**************************************

Secondly, I do appreciate the various comments on the Crow paper. I agree that Crow pointed out that modern medicine causes our population to retain more deleterious mutations. However, it seems clear to me that one of his statements ...

Quote:

If war or famine force our descendants to return to a stone-age life they will have to contend with all the problems that their stone-age ancestors had plus mutations that have accumulated in the meantime.

forces the unstated-by-Crow conclusion that our present population has a higher load of accumulated slightly deleterious mutations than our ancestors did. This conclusion is also supported by Crow's talk of the mutation accumulation problem being similar to the "population bomb" but with a much longer fuse. In discussing this paper with a microbiology professor from Ohio, he admitted something to the effect of "the human race is probably headed for mutational meltdown." I could provide the link upon request, but it would be some work.

In any case, if I am reading Crow right here, this overall picture from population genetics (corroborated by other geneticists) fits well with many Biblical statements regarding the initial "good" state of mankind, the subsequent Fall and Curse with its attendant death and suffering, the accounts of long-lived ante-diluvian patriarchs, and of the "groaning creation."

Hence my inference from these data that the earliest humans--Adam & Eve--were vigorous and healthy--much more so than modern man--and that naturally, without the aid of modern medicine. There is even a tradition in Whiston's notes on Josephus that Adam and Eve had 33 sons and 23 daughters(!) (Whiston's Josephus, p. 32, Footnote C). Biblical statements also cause us to think this health and vigor continued to some extent through the early post-Flood world, at which time recorded lifespans began decreasing.

So my theory is that ...

a) There was a Global Flood ~ 5000 ya
b) The Tower of Babel occurred within ~200 years of the Flood
c) Egypt, China and Sumeria were founded at this time (I take Rohl's New Chronology for Egypt which solves many Biblical enigmas)
d) The pyramids were built within a few hundred years of Babel
e) Population would have increased very quickly in the early post-Flood world for reasons already mentioned, thereby giving enough manpower to build great structures such as the pyramids.

I realize that I cannot be dogmatic with my theory, but I do feel it is well supported with what we know. Evidence is scanty when studying ancient history and we must do the best we can with what we have.

*************************************

Dean ... I appreciate your criticism RE: my wording. I always learn from those who disagree with me. I think you are correct about the MO for scholars and the MO for apologists. I do believe that we all operate as both to some degree in certain circumstances, and I feel that both roles are necessary. I view the scholar in a fact determining and the apologist in more of a fact proclaiming role ... both of which roles are found, I believe, on both sides of Origins and Biblical issues (my areas of interest).

Also ... from your NASA pages I was not able to find the 6-7 degrees you mentioned RE: Alpha Draconis. Do you have a quote?

HoverCraftWheel ... No, I don't own the Air Force. But my kids own a hovercraft (!) which they built from plans. I thought perhaps you owned one as well.

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