Freethought & Rationalism ArchiveThe archives are read only. |
03-03-2002, 03:34 PM | #61 | |
Veteran Member
Join Date: Mar 2001
Location: Louisville, KY, USA
Posts: 1,840
|
Quote:
To quote from my webpage on the Colorado Plateau: Modern Pollen in the Proterozoic Hakatai Shale: Disproof of Plant Evolution? In a 1966 CRS article, creationist C. L. Burdick claimed to have found modern pollen in the Hakatai Shale (Microflora of the Grand Canyon. Creation Research Society 1966 Annual 3(1):38-50). This finding was lauded by creationists as definitive "disproof" of plant evolution, and even today is presented as such on numerous creation "science" web sites. Unfortunately for Burdick and others who have promoted this claim, the supposed precambrian pollen is apparently nothing more than surface contamination. In 1980, another creationist, Arthur Chadwick of Loma Linda University, published an article in the journal Origins summarizing the results of his attempts to confirm Burdick's claims. Precambrian Pollen in the Grand Canyon - A Reexamination. Origins 8(1):7-12 (1981). He concluded: "A total of fifty samples from the same strata which Burdick had studied were processed. All slides were completely scanned. No single example of an authentic pollen grain was obtained from any of these samples. In fact, the slides produced from the Hakatai Formation were in most cases completely free from any material of biologic origin, modern or fossil." But what of Burdick's supposed precambrian pollen? Where did it come from? As Chadwick points out, the samples were taken from a surficially exposed portion of the Hakatai, and this immediately suggests contamination of modern pollen in Burdick's samples. This suggestion was amply confirmed by Chadwick, who notes: "No rigorous attempt was apparently made by Burdick to evaluate personally the modern pollen rain in the Grand Canyon. A single sample of soil from near one of the collecting sites could have completely satisfied Burdick as to the source of most of the grains he has reported. A typical analysis of a site near where Burdick collected his Hakatai samples yielded the following profile: bisaccate pollen (conifers) 30%; juniper 12%; ephedra 16%; various species of angiosperms (42%) (Sigels 1971). Although the poor quality of the photographs in the plates of Burdick's first paper makes definite assignments impossible, one can approximate the composition of the flora he reports. Of the grains identifiable as pollen or spores in the two papers by Burdick (n=18), 7 or 37% are bisaccates, 2 or 11% are possibly juniper. Ephedra pollen constitute 11% and angiosperms and unassignable grains 34%. Thus even with this small sample size, Burdick's grains approximate the modern pollen rain found in surface samples in the area of the Grand Canyon where he collected his samples" There are criteria for distinguishing between original pollen and pollen contaminates. For instance, ancient pollen should be darkly colored, not clear or yellowish like fresh pollen. In fact, the Hakatai was "baked" by intrusive igneous sills sometime after deposition. The pollen, if it was originally present, should be baked also. Chadwick again: "The preservation of the grains which Burdick figures in his first paper is difficult to estimate because of the poor quality of the photos. In the second paper the grains appear nearly fresh. The complete absence of organic material other than the pollen and spores cited by Burdick makes comparisons difficult, but many analyses from other Precambrian rocks where organic remains are thought to occur reveal little more than carbon films. Considering the deep burial, lithification, and oxidized condition of the Hakatai shales, the state of preservation of these grains suggests that they were not a part of these sediments during their diagenesis. Incidentally, the red color of the grains, cited by Burdick as an indication of their antiquity, if not due to laboratory staining procedures commonly employed, is in any case not necessarily an indication of antiquity since the ferruginous stain in the rocks can be readily acquired (as any Grand Canyon hiker will testify)." Which is the more likely scenario: a) the surface exposure of the Hakatai Shale in the Grand Canyon contains original pollen grains which just happen to match the pollen spectrum of the Grand Canyon area, while the overlying 10,000 ft of sediments contain no evidence at all of any metazoan life of any kind and the first indisputed pollen grains occur much higher still, or b) the supposed precambrian pollen grains are simply surficial contaminants which entered the exposed shale very recently, after the Hakatai bed was exposed by erosion? Chadwick notes that "More difficulties are created than are solved by Burdick's report since it would require the explanation of the accumulation of all the Upper Precambrian sediments (10,000 ft.), their lithification and subsequent erosion before the first additional fossil forms were buried. Add to this picture the many thousands of macerations of lower Paleozoic and Precambrian rocks which have been carried out in scores of palynology laboratories around the world which have not supported Burdick's claims. There is a general absence of evidence for flowering plants below the middle Cretaceous. It is a responsibility and challenge to creationists to develop a model of earth history which explains this absence." Last year I emailed Chadwick and asked him what he thought about the fact that AiG was still promoting this junk, and he told me that he thought the Precambrian pollen was as refuted as anything can be in science, and that he and Kurt Wise were wiring an article on the subject. I dont know if such an article has since appeared though. |
|
03-03-2002, 03:39 PM | #62 | |
Veteran Member
Join Date: Mar 2001
Location: Louisville, KY, USA
Posts: 1,840
|
Quote:
Oh, and the scriptures do in fact give a rough date for the flood, about ~2400BCE. Patrick |
|
03-03-2002, 04:56 PM | #63 |
Senior Member
Join Date: Jan 2002
Posts: 717
|
Ed, if you'd even bothered to read my previous post, you'd know that those characteristics must be the product of mutations or their population dynamics would be entirely different. Geez.
|
03-04-2002, 07:16 PM | #64 | |
Veteran Member
Join Date: Jun 2000
Location: SC
Posts: 5,908
|
Quote:
|
|
03-04-2002, 07:25 PM | #65 | |
Veteran Member
Join Date: Jun 2000
Location: SC
Posts: 5,908
|
Quote:
|
|
03-04-2002, 07:28 PM | #66 | |
Contributor
Join Date: Jul 2000
Location: Lebanon, OR, USA
Posts: 16,829
|
Quote:
|
|
03-04-2002, 07:55 PM | #67 | ||||||
Veteran Member
Join Date: Jun 2000
Location: SC
Posts: 5,908
|
Quote:
Quote:
Quote:
Quote:
Quote:
[b] Quote:
|
||||||
03-04-2002, 08:02 PM | #68 | |
Veteran Member
Join Date: Jun 2000
Location: SC
Posts: 5,908
|
Quote:
|
|
03-04-2002, 08:15 PM | #69 | |
Veteran Member
Join Date: Jun 2000
Location: SC
Posts: 5,908
|
Quote:
|
|
03-04-2002, 08:34 PM | #70 | ||||||
Contributor
Join Date: Jul 2000
Location: Lebanon, OR, USA
Posts: 16,829
|
Quote:
Quote:
Quote:
And Ed, what would cause you to reject Flood Geology? Quote:
Quote:
Quote:
Also, if I had to classify the Gospels, I'd call them "hagiography". |
||||||
Thread Tools | Search this Thread |
|