Feedback for June 2001

Swim bladders in modern fish apparently evolved from lungs, and the respiration function has been lost.

In either case, the main source of respiration for organisms with the first lungs was through the gills. Evolution is like that. It co-opts and modifies structures for new purposes. As lungs became more important for respiration in tetrapod evolution, gills became less important, until at some point gills were no longer contributing to respiration.

A link with some background: Sarcopterygii: Overview

The eye likewise has a very long evolutionary history, and living species demonstrate all kinds of gradations, thus demonstrating the viability of intermediate forms.

A link on evolution of the eye: How Could An Eye Evolve?

Darwin discusses both these examples in chapter 6 of Origin. It is interesting to note that Darwin speaks of the lung evolving from the swimbladder. We now know that the reverse is more likely the case; the lung most likely evolved as an aid to respiration, and was then co-opted as a swimbladder in the evolution of modern fish.

Ah, I see by the last sentence that Phil is a Robert Chambers fan, though what "The King in Yellow" has to do with evolution/creation issues is probably arguable.

Elliott Sober and David Sloan Wilson have addressed the issue of the evolutionary basis of altruistic behavior in a recent book, "Unto Others : The Evolution and Psychology of Unselfish Behavior".

Contrary to Phil's assertion, evolutionary biologists have on hand entire categories of evidence which were unknown to Darwin. For example, the entire field of genetics post-dates Darwin's publication of "Origin of Species".

I'm not sure what articles Phil would like us to stop writing, but as I see it many if not most of the articles available here are not about just talking about those people who agree with mainstream science, but rather are specifically directed to taking up and debunking the arguments of "evolution deniers".

I for one am not interested in "explaining away the creator". I'm much more interested in figuring out how the creator created. So far, it looks like the evolutionary biologists have the best account of the processes of creation. While chance is an important aspect of evolutionary process, it isn't the sole content of evolutionary mechanisms, and thus Phil's rhetoric delivers only a strawman.

Wesley

1) All items have a magnetic field, ...

Not true. Magnetic fields are "relativistic", as they exist only with reference to moving electric charges, and that motion is relative to the observer. It is quite possible for one observer to report a magnetic field, while another observer simultaneously reports no magnetic field, and both are correct. In the case of ferromagnetism, the external magnetic field is caused by a parallel alignment of magnetic domains inside the material, but that magnetic alignment breaks down at high temperatures. The Earth's core cannot have a ferromagnetic field because it is hotter than the Curie temperature.

2) The dynamo theory is proofless, boundless, thoughtless and nothing more than evlutionary escapism.

You make several other, similar statements, but offer no support other than the fact that you assert this to be the case. You are quite wrong; dynamo theory has long since been well established in physics, and to deny it at this stage of the game is beyond the realm of reason in all senses of the word.

4) ... the only evidence we have is that the known rate of magnetic field decay makes life impossible not long ago.

I thought creationists did not make unwarranted "uniformitarian" assumptions. Or perhaps they do it only when convenient? In any case, this is one of them. The evidence we have is that, over a time span of about 130 years, the dipole component of the Earth's magnetic field was seen to decrease by about 6.3%, although with some undetermined uncertainty. Furthermore, the actual pattern shows a decrease that took only 100 years, while the following 30 years shows no substantial change (see table 2 in my article).

Any assumptions about what the magnetic field did before, or will do in the future, must be based on something. Barnes claimed to prove that the pattern was exponential. His claim was not just false, but very false; however, even if true it would not have justified the outrageous conclusion that it must always have been so. His backwards extrapolation over 10,000 years, based on an empirical fit to a 150 year baseline falls well beyond the limits of acceptability.

Geological & geophysical evidence, on the other hand, clearly shows that the dipole component of the field has reversed itself numerous times (see my article and the references at the end). That evidence is so strong that even D. Russell humphreys, arch young-Earth creationists, accepts the reality of past field reversals (although he disputes the time scale).

7) ... Polonium 214 can't halo in soilid rock, or biotite, no matter how long "fissures" allow the path of Radon to has penetrate into it.

This is not an issue covered by my article on the Earth's magnetic field. See "Evolution's Tiny Violences: The Po-Halo Mystery". The bottom line is that Po-214 certainly can do exactly that, if it is part of the well established U-238 decay chain. Not only can Gentry not distinguish the halo of Po-214 from Rn-222, but he only finds Po isotopes that come from the U-238 decay chain, and he only finds them in proximity to U-238 deposits. It does not look like much of a mystery to me.

Your text is probably taken from a very recent article by Roger Highfield, a science editor for the Electronic Telegraph. It appears in the June 30, issue and is available on-line at the time of writing this response.

Dr Richards has a home page from which you can find some of his publications.

The work in question is published in the latest issue of Science, June 29, 2001, as "Extremely large variations of atmospheric 14C concentration during the last glacial period", by J.W. Beck et al.

One of Dr Richards' research interests is the calibration of radiobarbon dating. This involves checking the dates using other independent methods. The main source of systematic error in radiocarbon dating is the varying concentration of carbon-14 in the atmosphere in the past. Dr Richards and his colleagues have found good evidence of increased levels beyond about 30,000 years ago, with a very substantial peak around 43.3 to 44.3 thousand years ago, by studies of a stalagmite.

They consider increased cosmic radiation from a supernova as a possible explanation for increased generation of C14 in the atmosphere around that time.

There have been many other studies allowing calibration of atmospheric radiocarbon by various independent means; the study by Richards and his co-authors largely confirms and refines those calibrations; the finding of a large peak is a new result going beyond the limits of previous calibrations.

The large peak they found is a new and interesting result, though it has no effect except for dates extending back over 33 thousand years.

In summary, this work confirms the principles of radiocarbon dating, confirms and refines existing calibration of radiocarbon dates from 11,000 to something like 24,000 years, extends calibration back to 45,000 years, leading to some significant corrections for dates greater than 30,000 years. These corrections mean that some published dates may be too young. No major change for dates less than 30,000 years is indicated, and an interesting peak was found near the end of their range of study.

There is, of course, not the slightest comfort for young earth creationists in these results. There may be cause for some substantial adjustments to published dates for some studies, such as Neanderthal sites, making them a bit older than previously thought, by up to 20%.

"Well, we are now about 120 years after Darwin and the knowledge of the fossil record has been greatly expanded. We now have a quarter of a million fossil species but the situation hasn't changed much. The record of evolution is still surprisingly jerky and, ironically, we have even fewer examples of evolutionary transitions than we had in Darwin's time. By this I mean that some of the classic cases of darwinian change in the fossil record, such as the evolution of the horse in North America, have had to be discarded or modified as a result of more detailed information -- what appeared to be a nice simple progression when relatively few data were available now appear to be much more complex and much less gradualistic. So Darwin's problem has not been alleviated in the last 120 years and we still have a record which does show change but one that can hardly be looked upon as the most reasonable consequence of natural selection."(p. 25)

Note that while Raup says that some of the examples have been "discarded" he also says that others have only been "modified". For example the classic horse series Raup mentions is one of those that has been modified, but it is far from discarded. Also note that Raup clearly states that the pattern of the fossil record is one of change in living things over geologic time, something that young earth creationists deny.

And yes it has been taken out of context. The paper is about Darwin's mechanism of natural selection and whether this mechanism is reflected in pattern of the fossil record, not whether there is a lack of evidence for common descent. From the beginning of the article:

"Part of our conventional wisdom about evolution is that the fossil record of past life is an important cornerstone of evolutionary theory. In some ways, this is true -- but the situation is much more complicated. I will explore here a few of the complex interrelationships between fossils and darwinian theory. . . Darwin's theory of natural selection has always been closely linked to evidence form fossils, and probably most people assume that fossils provide a very important part of the general argument that is made in favor of darwinian interpretations of the history of life. Unfortunately, this is not strictly true. We must distinguish between the fact of evolution -- defined as change in organisms over time -- and the explanation of this change. Darwin's contribution, through his theory of natural selection, was to suggest how the evolutionary change took place. The evidence we find in the geologic record is not nearly as compatible with darwinian natural selection as we would like it to be." (p. 22)

The transitions Raup seems to be talking about in the quote creationists use are mostly at the level of species or genera (like between a horse and a zebra or between a fox and a wolf), not intermediates between higher classifications like between classes, orders, or families (between reptiles and mammals etc.), which are the ones creationists most object to. However it is these "missing" species level transitions that creationists (in ignorance?) often quote paleontologists talking about. This seems to be the case here as well:

"There were several problems, but the principle one was that the geologic record did not then and still does not yield a finely graduated chain of slow and progressive evolution. In other words, there are not enough intermediates. There are very few cases where one can find a gradual transition from one species to another. . ." (p. 23, emphasis mine)

Stephen Jay Gould and Niles Eldredge are favorite targets for this creationist tactic because their hypothesis of punctuated equilibria is intended to explain why from a biological point of view we should expect species level transitions to be rare in the fossil record. Thus in their writings they frequently state the problem(s) they are attempting to solve. Creationists quote them stating the problems but not the solutions they propose. This seems to be the nature of the quote they have taken from Raup. The beginning of the very next paragraph after the one they quote tends to confirm this:

"Now let me take a step back from the problem and very generally discuss natural selection and what we know about it. I think it is safe to say that we know for sure that natural selection, as a process, does work. There is a mountain of experimental and observational evidence, much of it predating genetics, which shows that natural selection as a biological process works."(p. 25)

He then moves on to the fossil record:

"Now with regard to the fossil record, we certainly see change. If any of us were to be put down in the Cretaceous landscape we would immediately recognize the difference. Some of the plants and animals would be familiar but most would have changed and some of the types would be totally different from those living today. . . This record of change pretty clearly demonstrates that evolution has occurred if we define evolution simply as change; but it does not tell us how this change too place, and that is really the question. If we allow that natural selection works, as we almost have to do, the fossil record doesn't tell us whether it was responsible for 90 percent of the change we see or 9 percent, or .9 percent." (p. 26)

He then goes on to discuss natural selection versus other possible explanatory mechanisms and how they might relate to the fossil record. He also discusses the effects of historical contingency as it relates to extinction pointing out that sometimes species may become extinct due more to "bad luck" than bad genes -- this by the way is the basis for Raup's 1991 book Extinction - Bad Genes or Bad Luck?). Raup concludes this article stating:

"The ideas I have discussed here are rather new and have not been completely tested. No matter how they come out, however, they are having a ventilating effect on thinking in evolution and the conventional dogma is being challenged. If the ideas turn out to be valid, it will mean that Darwin was correct in what he said but that he was explaining only a part of the total evolutionary picture. The part he missed was the simple element of chance!"(p. 29)

Not particularly damning. Perhaps the more interesting question is where do creationists get the idea that lists of such (out of context) quotations are a valid form of scientific arguement?

For Raup's views on creationist arguments I suggest you look up one or both of the following:

"Geology and Creationism", Field Museum of Natural History Bulletin Mar. 1983, Vol. 54 No. 3 pp. 16-25)

"The Geological and Paleontological Arguments of Creationism" in Scientists Confront Creationism (1983), Laurie R. Godfrey (Editor), pp. 147-162

The law of universal gravitation, Maxwell's equations describing electromagnetism, and the germ theory of disease are all every bit as un-Biblical as evolution. I assume you reject them for the same reason you reject evolution?

Actually, there was no deliberate attempt to seek out and include Christian evolutionist comments. The archive was started by a fairly random collection of folks who were regular on the talk.origins newsgroup. Some of them were Christians, some weren't. Some FAQs written by Christians have nothing to indicate that they happen to be by a Christian. Others written by atheists have nothing to indicate that they happen to be by an atheist. What is common to contributors is an interest in evolutionary biology, and recognition of a need for a resource to address some common confusions on that subject.

Mark originally asked for the selective advantage that accompanied each intermediate stage in the history of the mammalian middle ear impedance matching system. My response was that we do not know whether selection or drift accounts for the formation of the intermediate states that we know existed. What we can exclude with confidence is the de novo insertion of this as an IC structure into early mammals. Whether we will be able to reconstruct a series of selective gradients to go with the detailed fossil record of this system is an open question. What is not open is the fact that these various intermediate states are recorded in the fossil record, and cannot simply be dismissed as "correspondingly unlikely" by intelligent design proponents. I'll repeat my previous response since its central message seems not to have gotten through the first time.

We may not know what selective advantage, if any, the intermediate stages of the mammalian middle ear had over their precursor arrangements. What we do know is that these intermediate stages did exist and that the final state of the system has the property of irreducible complexity with respect to the function of impedance matching in the mammalian auditory system. While IC arguments may not in principle say that intermediate states cannot exist, in practice Dr. Behe and others invoking IC routinely imply that IC-ness is incompatible with accounts premised on natural selection and that genetic drift is insufficient to explain such systems. We don't know whether natural selection or genetic drift was operating exclusively or alternately in the production of the irreducibly complex impedance-matching system of the mammalian middle ear, but we do have evidence from the fossil record that it evolved over a period of some millions of years, and was not inserted at any one point by an "intelligent designer". If even genetic drift can be said to lead to IC structures (as rejection of selective pathways in this case would suggest), then the exclusionary logic of IC as evidence for an intervening intelligent designer is in even more trouble than if one simply assumed natural selection as an operative mechanism.

That said, there certainly is a prospect that selective advantage of intermediate steps could be approached as a topic for research based upon models of hearing. The field of modeling functional morphology in audition has several publications in determining the probable hearing range of extant odontocetes. It may only be a matter of time before someone turns their attention to this interesting set of fossil data to determine the auditory properties of the various systems as recorded in the fossils of the transitional sequence.

Wesley

"Jur'y-rigged', adj. Naut. Rigged for temporary use."

And an on-line dictionary (on CompuServe) lists the following:

Main Entry: ju·ry-rig Pronunciation: 'jur-E-"rig, -'rig Function: transitive verb Etymology: 2jury Date: 1788 : to erect, construct, or arrange in a makeshift fashion

So, you were saying?

Waddington, CH. The Evolution of an Evolutionist. Edinburgh: University of Edinburgh Press, 1975.

More recent discussions include the following:

Kauffman, Stuart A. At Home in the Universe: The Search for Laws of Self-Organization and Complexity. New York: Oxford University Press, 1995.

———. The Origins of Order: Self-Organization and Selection in Evolution. New York: Oxford University Press, 1993.

Kauffman's work deals with the mathematisation of evolution in a systems theory approach.

Michod, Richard E. Darwinian Dynamics: Evolutionary Transitions in Fitness and Individuality. Princeton, N.J.: Princeton University Press, 1999.

Michod's book is an attempt to summarise the mathematical dynamics of evolution.

The feedback system does a bit of processing for links, but it is not perfect. It sometimes generates an anchor in the middle of an existing anchor. We have the chance to check for such problems, but I failed to check in this instance.

Comically, the links you provided in your feedback fail after processing for a similar reason! I have taken the liberty of editing your comments to resolve the problem. (This could get recursive if I muck it up again!)