I have taught Science classes for a while and have studied evolutionary theory (which, by the way is defined as something that can be tested, and is really only a hypothesis). When I teach evolutionary theory, I also include all the problems evolutionary bioligists have with their theory, like "Dating methods using use circular dates, archaeopteryx, transitional forms, Java, Piltdown, and Neanderthal man, life to non-life impossibilities, mutations, astronomical mathematical probabilities, defiance of scientific laws (entropy. Etc.), and several more. I have a real problem with teaching evolution as fact when only 6% of the US population believes Evolution alone should be taught in schools. I would suggest that neither evolution or creation of any kind be taught in science classrooms, since they both fail the scientific method test (cannot be scientifically repeated). Any teaching about origins should be in a phylosophy or religion class, since neither are really science. Tom Kabel.
I find it hard to believe that Tom Kabel is a science teacher in a public school. It is possible- too possible- but hard to believe. I would hope that teachers could spell, and present a reasoned, logical argument. Evolutionary biologists don’t have any problem with the age of the earth. Evolution happened, and however much time is available is the amount of time it took. The pace and tempo of evolutionary change is actually an active area of study, and very practical given the current high rate of species extinctions. However, Tom wants to have dating explained. The fact is that sedimentary sequences were worked out in the late 1700s and early 1800s. The core material data for all sedimentary studies is a location were there are multiple deposited strata resting on top of one another in what are called "clean" or "conforming" contacts. It was realized over 200 years ago that the fossils contained within the various strata were a useful characteristic that could be used to correlate strata from distant locations. This didn't assign any "age" to the rock, but placed it within a confirmed sequence. This was quite useful and was used commercially to discover new coal fields as early as the 1820s. Nobody new how old these rocks might be until the middle 20th century. The discovery of radioactivity in the late 1800s and the confirmation of the atomic structure of elements in the 1920s allowed for the application of radioactive decay to the question of how old are rocks (and the earth). Since the 1960s the excellent match between stratigraphic sequence and radiometric dates has enabled some shortcuts to be used when 1) the exact age of a strata is not particularly important, or 2) where there is an absence of directly datable rock, and I might also add 3) where there is just not enough money for lab work. But, "biostratigraphic" dates are not considered as reliable as absolute dates.
Neil77 wrote:houston_res wrote:
"I don't know what weaknesses in the theory of evolution they plan to discuss."
Well, since you asked, here are just a few:
1) The Cambrian explosion
2) The Miller-Urey experiment requires an atmosphere that can not exist naturally
3) Heckel's drawings are known fakes
4) The peppered moth experiment was altered (they don't naturally rest on tree trunks, the experimenter physically placed them there, etc.)
5) The fossil record shows certain species to be older than their predecessors.
6) Macroevolution can not account for the existence of the cell
Now, none of these (excepting the Cambrian explosion) are actually evidence AGAINST evolution. They simply show that much of the evidence FOR it is nonexistent. The truly irritating argument to someone who knows anything about science is the gravity argument. Yes, they are both theories, but gravity is what is known as a FALSIFIABLE theory. This means that if it were false, there would be an experiment capable of proving it so. Evolution is not falsifiable. Another major irritation is the ignorance of the difference between micro- and macro-evolution. Microevolution is observable and, as much as anything is, provable. Macroevolution is not only unprovable, but has no evidence to support it that is also capable of supporting several other possibilities.
6/3/2008 11:51 AM CDT
It is hard to choose between Neil77's PRATT list (Points Refuted Thousands of Times), or dbldwn88. The pace at which these comments are flowing is remarkable.
Here is an easy one, "2) The Miller-Urey experiment requires an atmosphere that can not exist naturally"
The Miller-Urey experiment published in 1953 demonstrated that essential amino acids formed when a gas mixture of water vapor (H2O), carbon monoxide (CO), hydrogen (H2), ammonia (NH3) and methane (CH4) were sparked by electricity. The particular mixture of gasses was selected because it reflected the gas abundance seen in the outer solar system which are the least altered because of their distance from the sun. At the time, geochemists were divided on the question of what the earliest earth atmosphere was like, and from the 1970s to the middle 1990s the majority opinion was that there was likely a mixture of carbon dioxide (CO2) instead of CO, nitrogen (N2), and much less of the other gasses used by Miller. This has been misrepresented by creationists as "proof" that evolution (incorrectly linked to the origin of life) is refuted.
In fact, recent studies have conclusively demonstrated that the gasses on the earliest earth were closer to the Miller-Urey experiment than the more oxidized mix suggested during the 1980s. However, in a truly fitting irony, the last paper ever written by Stanley Miller (published this year posthumously) has demonstrated that even an atmosphere with traces of free oxygen can yield excellent amounts of amino acids;
Miller, Stanley L.,
1953 “A Production of Amino Acids Under Possible Primitive Earth Conditions” Science vol. 117:528-529
Cleaves, H. James, John H. Chalmers, Antonio Lazcano, Stanley L. Miller, Jeffrey L. Bada
2008 “A Reassessment of Prebiotic Organic Synthesis in Neutral Planetary Atmospheres” Orig Life Evol Biosph (2008) 38:105–115
So, the creationists are once again without an argument.
6/3/2008 12:53 PM CDT
These are like potato chips. “4) The peppered moth experiment was altered (they don't naturally rest on tree trunks, the experimenter physically placed them there, etc.)”
The peppered moths (Biston betularia) were a largely light colored moth with dark specks on its wings. During the industrialization of England, coal burning factories produced large amounts of soot that darkened the trees the moths rested in during the daytime. Over the course of the 1800s, the light pattern moth nearly disappeared and was replaced by an almost black form. It was proposed that this was an example of adaptive change supporting Darwinian natural selection. When environmental laws were passed in the 1940s in England, the trees began to shed their coating of soot, and the light colored moths made a reappearance. In the 1950s Bernard Kettlewell studied this recovery of the light colored moth and concluded that birds had found the moths more easily when they were of contrasting color with the trees where they rested.
There were two biologists, Bruce Grant and Michael Majerus who published criticisms of Ketterwell’s experiments. Grant, who had a personal grudge against Kettlewell, insisted that the moth’s ability to choose a resting place would have compensated for the soot covered trees, and that some other evolutionary force was responsible for the observed changes. Majerus thought that Kettlewell’s experiment could be greatly improved on technically, and that until someone (like himself) was well funded for many years, the Kettlewell result should be doubted. Biologist, critic and grumpy-old-man Jerry Coyne wrote an overblown review of Majerus’s complaints that was published in the journal “Nature,” and the creationists were all over the story like flies. New-Age science journalist Judith Hooper wrote a whole book about Bruce Grant’s hurt feelings and even hinted that Kettlewell had faked his data. Then Jonathan Wells, Intelligent Design Creationists, Discovery Institute Senior Fellow and ordained Rev. Sun Moon worshiper, wrote his “Icons of Evolution” that claimed the peppered moths were faked, and that peppered moths never rested on tree trunks.
These were all lies, of course.
The famous photo was not the basis of Kettlewell’s results- he merely used a photo of light and dark patterned moths next to each other to illustrate how easy it is to see the difference. Majerus has finished his improved experiments and discovered that Kettlewell had been correct all the time. For more information use the links below.
August 28, 2007
http://pandasthumb.org/archives/2007/08/peppered-moths.html
November 27, 2007
http://pandasthumb.org/archives/2007/11/peppered-moths-1.html
Here is one for dbldwn88, who wrote, “… life is not propagated by amino acids, but nucleic acids. Completely different molecules. And the nucleic acids that code for amino acids ONLY code for L-isomeric amino acid proteins. The probability of life arising spontaneously from nucleic acids that only code for L isomers is astronomical.”
I have written a bibliographic outline for the origin of life, but it far too long to use on this venue. Just some highlights regarding the abiotic origin of nucleic acids, and chirality;
Nucleosides;
Fuller, W. D., Sanchez, R. A. & Orgel, L. E. Studies in prebiotic synthesis. VI. Synthesis of purine nucleosides. J. Mol. Biol. 67, 25-33 (1972).
Robertson, MP, Miller SL.
1995 An efficient prebiotic synthesis of cytosine and uracil. Nature 375, 772 - 774 ()
Nelson K.E., Robertson M.P., Levy M, Miller S.L.
2001 Concentration by evaporation and the prebiotic synthesis of cytosine. Orig Life Evol Biosph Jun;31(3):221-229
Chirality;
Antonio Chrysostomou, T. M. Gledhill,1 François Ménard, J. H. Hough, Motohide
Tamura and Jeremy Bailey
2000 "Polarimetry of young stellar objects -III. Circular polarimetry of OMC-1" Monthly Notices of the Royal Astronomical Society Volume 312 Issue 1 Page 103 - February
Michael H. Engel and Bartholomew Nagy,
1982 "Distribution and Enantiomeric Composition of Amino Acids in the Murchison Meteorite", Nature , 296, April 29, , p. 838.
Jeremy Bailey, Antonio Chrysostomou, J. H. Hough, T. M. Gledhill, Alan McCall, Stuart Clark, François Ménard, and Motohide Tamura
1998 Circular Polarization in Star- Formation Regions: Implications for Biomolecular Homochirality Science 1998 July 31; 281: 672-674. (in Reports)
Chyba, Christopher F.
1997 Origins of life: A left-handed Solar System? Nature 389, 234- 235 (18 Sep 1997)
Engel, M. H., S. A. Macko
1997 Isotopic evidence for extraterrestrial non- racemic amino acids in the Murchison meteorite. Nature 389, 265 - 268 (18 Sep)
Creationists like to present this as a profound mystery that is supposed to "prove" that they are correct. I want to mention a neat instance where both left and right amino acids are used in a living thing. It is very rare, but it does happen. Next time a creationist claims to be an "expert" and that amino acid chirality "proves" something supernatural, you can gob-smack-em. The protein is called Gramicidin A and it has 8 L-amino acids, 6 D-amino acids, and one glycine which is an amino acid that is neither L- or D- in its structure. I have found that even many biologists will bet an "adult beverage" that all proteins are exclusive L- amino acids.
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