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Thursday 24 July 2014

"20 scientific facts seldom taught to students" critically reviewed #16

Collyer's 16th 'scientific fact seldom taught to students' was his assertion that "[f]ossils are evidence of extinctions, not of new forms of life". Added to that was his implicit assertion that fossils provided support for a flood when he claimed that "[t]heir condition is evidence of very rapid burial. Finally, he claimed that "many polystrate fossils indicate that several strata were laid rapidly round the upright fossil."

His reference to fossils being evidence of extinction, not of new forms of life is incorrect.  When a fossil appears for the first time in the geological record, and is preceded by a similar organism, it is entirely reasonable state that this is evidence for the appearance of a new species. 

There is no such term as “polystrate fossil” in the geological literature, as it is one that was invented by creationists to describe phenomena that appear to support flood geology. Trees buried in sediments don't always die immediately, but can remain there for many years, while further layers are added. 19th century old earth creationist geologists explained these phenomena using standard geological methods.

Fossils, Extinction and the appearance of new life

The fossil record details the history of life on Earth from the earliest chemical evidence of life, through to multicellular life which becomes progressively more complex as we move through time. A number of mass extinction events can be seen through the fossil record, in which many classes of life are wiped out, and the process of diversification (adaptive radiation) continues afresh. It is – to be honest – difficult to point out just how poorly Collyer understands palaeontology if he believes fossils are evidence of extinction, rather than new forms of life.

Palaeontologist Paul Taylor, in an article on extinction and the fossil record points out that:
While species of some prokaryotes may be extremely long-lived...species of multicellular eukaryotes in the Phanerozoic fossil record commonly become extinct within 10 million years (Ma) of their time of origin, with some surviving for less than a million years. Entire groups of previously dominant animals and plants have succumbed to extinction, epitomized by those stalwarts of popular palaeontology, the dinosaurs. The extinction of dominant clades has had positive as well as negative consequences -- extinction removes incumbents and opens the way for other clades to radiate. For example, without the extinction of the incumbent dinosaurs and other ‘ruling reptiles’ 65 Ma ago, birds and mammals, including humans, would surely not be the dominant terrestrial animals they are today. [1]
His last point emphasises Collyer's regrettably poor grasp of the subject. When one class of life becomes extinct, and is followed by a massive adaptive radiation of species of another type of animal, many of which exploit the niche, we have unarguable evidence of the evolution of new forms of life, as well as evidence that extinctions as Taylor notes, have a positive effect in clearing the path for new life to appear.

While transitions between species are uncommon, partly due to the nature of allopatric speciation [2] and partly due to the vagaries of the fossil record,  we do have marvellously detailed examples of large-scale evolutionary change and speciation in fine detail. Vertebrate palaeontologist Donald Prothero notes:
Let us look at just one more classic example, probably the most extreme change in morphology ever documented in the fossil record. If you look at samples of microfossils from the middle Eocene (50 million years ago), you will find distinctive spongy ball-shaped radiolarians known as Lithocyclia ocellus (fig. 8.7). As you trace the spongy balls up through the sediments spanning millions of years, you see them gradually lose their spongy outer layers and develop into a small nucleus with four spongy arms (Lithocyclia aristotelis), then three arms (Lithocyclia angusta), and finally reduced to two arms forming a spindle-like shape (Cannartus tubarius). The Cannartus lineage then gradually develops a “waist” on the central sphere, then the arms get shorter and thicker, and finally, they split into two lineages: Cannartus peterssoni-Ommatartus hughesi, which evolves into a form with two arms with multiple spongy layers, and Ommatartus, which develops shorter arms and a fatter central sphere. If you look at the two extremes (a spongy sphere turning into a spindle-shaped shell with multiple caps), you could never imagine that they are closely related—yet I have looked at the slides from those cores and seen the gradual transition from one extreme to the other with my own eyes. [3]



Figure 8.7. Evolutionary transformation in the cannartid-ommatartid lineage of radiolaria over the past 50 million years, from spongy balls to four- and then three-armed and finally two-armed bipolar structures, with further variations in the spongy caps later in their evolution. Taxa are as follows: 26, Lithocyclia ocellus; 27, Lithocyclia aristotelis; 28, Lithocyclia angusta; 30, Cannartus tubarius; 31, Cannartus violina; 32, Cannartus mammiferus; 33, Cannartus laticonus; 34, Cannartus petterssoni; 35, Ommatartus hughesi; 36, Ommatartus antepenultimus; 37, Ommatartus penultimus; 38, Ommatartus avitus; 39, Ommatartus tetra thalamus
Source: Prothero D "Evolution: What the Fossils Say and Why it Matters."
Rapid burial is not necessary for fossilisation to occur
A commonly-asserted YEC claim is that rapid burial is essential for fossilisation to occur, with the implication being that this somehow proves that all fossils were created by a massive flood. This assertion, that rapid burial is essential for fossilisation to occur is inaccurate. Geologist Keith Littleton points out that:
Bones can survive for over a year before being buried. In the case of shells, they can be washed around for decades, even hundreds of years, before they are finally buried in the sediment to become fossils. Only in the fossilization of soft parts is immediate burial required. This all has been documented by direct field observation and other studies…[T]he hard parts of animals can persist for a significant period of time before being finally buried. In fact, the degree to which many fossil shells are either encrusted or have been bored by other organisms and bones which show signs of either weathering or gnawing demonstrates that they were not rapidly buried before being fossilized. Of course, a bone or shell eventually has to be buried to be preserved. [3]
It also should be noted that rapid burial can occur in local events such as  landslides and regional floods. Rapid burial is not contingent on a global flood.

There are no such things as 'polystrate fossils'

Collyer's reference to “polystrate fossils” betrays both his lack of familiarity with geology and palaeontology, as well as his uncritical reliance on young earth creationist sources. For a start, the term “polystrate fossil” is not a term used by geologists, but rather is one employed by flood geologists. Andrew McRae notes:
Some creationist presentations include claims about "polystrate fossils". From the description, this term is used for fossils which intersect several beds (layers), usually in sedimentary rocks. Although often used in creationist literature, I have been unable to determine the origin of the term -- it is not a standard geological term. This makes it difficult for the uninitiated to find conventional literature about these fossils. [94]
Andrew McRae points out that this alleged problem was noted, and solved by 19th century geologists who did not resort to flood geology:
Well, they were not a problem to explain in the 19th century, and are still not a problem now. John William Dawson described a classic Carboniferous-age locality at Joggins, Nova Scotia, where there are upright giant lycopod trees up to a few metres tall preserved mainly in river-deposited sandstones. These trees have extensive root systems with rootlets that penetrate into the underlying sediment, which is either a coal seam (i.e. compressed plant material), or an intensely-rooted sandstone or mudstone (i.e. a soil horizon). Dawson considered and rejected anything but an in situ formation for these fossils, and his interpretation is closely similar to current interpretations of sediments deposited on river floodplains. An interesting feature of these examples is the presence of vertebrate fossils (mostly small reptiles) within the infilling of the stumps.
McRae continues – he is worth quoting at considerable length if only to refute Collyer’s factually inaccurate and outdated argument:
In article <1994May22.133828.562@alc-ohio.alc.com> malone@alc-ohio.alc.com (Bruce Malone) writes:
"[...] 
"Fossil trees trunks, which extend upward through multiple layers of limestone, have been found in many areas of the world including Kingston, Ontario [there are no such trees in Kingston, Ontario -AM] and Joggins, Nova Scotia [emphasis added]. 
"This suggests that these very thick deposits were deposited very rapidly. Similar polystata trees have been found extending upright through successive seams of coal. Some of these trees have supposedly stood upright while successive cycles of oceans and peat swamp have pasted through an area. You be the judge as to the most logical interpretation... slow accumulation over thousands of years or... rapid burial during a massive world wide flood."

One of the best, and longest-known "fossil forest" occurrences is a locality known as Joggins, in Nova Scotia. It is Carboniferous in age, and was first described in detail in the late 1800s. Here is a quote from Dawson 1868 (pp. 179-180) on the nature of the trees at this locality, in a beautiful cliff section over 1km thick:

"In the [stratigraphic] section in the preceding chapter, the reader will observe the words 'Underclay, Stigmaria [a type of fossil tree trunk]' frequently recurring; and over nearly every underclay is a seam of coal. An underclay is technically the bed of clay which underlies a coal-seam; but it has now become a general term for a fossil soil [Dawson's emphasis], or a bed which once formed a terrestrial surface, and supported trees and other plants; because we generally find these coal underclays, like the subsoils of many modern peat-bogs, to contain roots and trunks of trees which aided in the accumulation of the vegetable matter of the coal. The underclays in question are accordingly penetrated by innumerable long rootlets, now in a coaly state, but retaining enough of their form to enable us to recognize them as belonging to a peculiar root, the Stigmaria, of very frequent occurrence in the coal measures, and at one time supposed to have been a swamp plant of anomalous form, but now known to have belonged to an equally singular tree, the Sigillaria, found in the same deposits. The Stigmaria has derived its name from the regularly arranged pits or spots left by its rootlets, which proceeded from it on all sides. The Sigillaria has been named from the rows of leaf-scars which extend up its trunk, which in some species is curiously ribbed or fluted. One of the most remarkable peculiarities of the stigmaria-rooted trees was the very regular arrangement of their roots, which are four at their departure from the trunk, and divide at equal distances successively into eight, sixteen, and thirty-two branches, each giving off, on all sides, an immense number of rootlets, stretching into the beds around, in a manner which shows that these must have been soft sand and mud at the time these roots and rootlets spread through them. 
Stratigraphy in association with an upright tree stump, Joggins, Nova Scotia. 
Figure 41 of Dawson [1] 
Original Caption: 
"1.=Shale. 2.=Shaly coal, 1 foot. 3. Underclay with rootlets, 1 foot 2 inches. 4. Gray sandstone passing downwards into shale, 3 feet. Erect tree with Stigmaria roots (e) on the coal. 5. Coal, 1 inch. 6.Underclay with roots, 10 inches. 7. Gray sandstone, 1 foot 5 inches. Stigmaria rootlet continued from the bed above; erect Calamites8. Gray shale, with pyrites. Flattened plants." Source: TalkOrigins

"It is evident that when we find a bed of clay now hardened into stone, and containing the roots and rootlets of these plants in their natural position, we can infer, 1st, that such beds must once have been in a very soft condition; 2ndly, that the roots found in them were not drifted, but grew in their present positions; in short, that these ancient roots are in similar circumstances with those of the recent trees that underlie the Amherst marshes [these are local tidal marshes, some with recently-buried forest layers in the peat and sediment]. In corroboration of this, we shall find, in farther examination of this [stratigraphic] section, that while some of these fossil soils support coals, other support erect trunks of trees connected with their roots and still in their natural position."
There is very little, with the exception of terminology, that would be different in a "modern" interpretation of these features, and Dawson has much more detail on the other sedimentological features found at Joggins that support his interpretation. Dawson records well over a dozen horizons with large upright trees, and smaller ones are even more common. The section at Joggins can still be visited today, and is particularly well-known for the small reptile fossils found there (they often occur inside the upright tree stumps, apparently they fell in the hollow stump). There are usually a few upright trees exposed on the shore, although the rapid erosion of the 10m+ high cliffs means the exposed examples change every year.
Given that an "in place" occurrence was convincingly determined by observations made in the 19th century for this and many other "fossil forest" localities, it is surprising that these conclusions have not been recognized by modern "young Earth global flood" [YEGF] creationists as clear evidence of non-global-flood deposition for much of the geologic record. They often hinge their current arguments on the occurrence of upright trees in Yellowstone National Park, point to their volcanic setting, and then point to floating upright trees floating in Spirit Lake near Mt. St. Helens, and say, "See? They could be transported during the flood.". This argument is completely fallacious, because most "fossil forests" do not occur in volcanic deposits, and do have the fragile roots of the stumps tightly penetrating into the surrounding sediment, often into a paleosol (fossil soil)... One occurrence is even associated with dinosaur footprints on the same surface, on top of a coal seam. The "transported floating upright stumps" model is a complete red herring that does not apply to the vast majority of "fossil forest" occurrences. 
As for Malone's "problem" with the "thousands of years" for the tree to remain upright for "slow accumulation" to occur, it is a non-problem - he is simply interpolating the average depositional rates for an entire formation down to the scale of metres. This is not the correct way to do it, because individual beds can be deposited rapidly (say, sands and mud during a levee breach), and then little deposition can occur for a long time (e.g., a soil horizon), as is observed in modern river floodplain environments where trees commonly occur. In short, he is assuming conventional geologists would interpret the occurrence the simple way he has interpolated - they do not. 
One of the most compelling features of Dawson's comments, from a YEGF creationist's perspective, may be the closing remarks of his book, in the conclusion section on p.671. Statements expressing similar sentiments can be found in most geological books of the period (e.g., Murchison's "Siluria", where the Silurian and other Paleozoic systems are first defined):
"Patient observation and thought may enable us in time better to comprehend these mysteries; and I think we may be much aided in this by cultivating an acquaintance with the Maker and Ruler of the machine as well as with His work."

Dawson has no theological problems with the conclusions he drew, which are basically similar to the ones drawn by geologists now. Many other geologists of the period were devoutly religious, and clearly expressed the fact in their publications. 
Apparently, many 19th century geologists share a common philosophical framework with modern creationists, but, strangely enough, modern creationists come to completely different conclusions from both the 19th century geologists and current geologists. The common appeal by modern creationists to an "atheistic" or "humanistic" philosophical framework that "taints" the interpretations of science is quite ridiculous in light of the strong beliefs of many historical scientists, particularly in geology. Why should creationists still have a problem with their conclusions, more than 100 years later? 
Malone, along with many "young Earth global flood creationists", have no idea that even data from the 19th century, presented by a creationist geologist is enough to demolish the "polystrate fossil trees" part of their presentation. "Polystrate fossil trees" are probably one of the weakest pieces of evidence YEGF creationists can offer for their interpretation. I wish they would stop using it. (Emphasis mine) 
The only comment I wish to add to McRae’s emphatic demolition of the polystrate fossil argument is that the 19th century believing geologist John William Dawson had a far more nuanced and sophisticated view of the two books of creation than 21st century Christadelphians. 

References

1. Taylor P.D. "Extinction and the Fossil Record" in Extinctions in the History of Life (2004: Cambridge University Press)


3. http://www.talkorigins.org/origins/postmonth/sep02.html

4. McRae A “Polystrate Tree Fossils TalkOrigins Archive (1994-1997)