g-rh@cca.UUCP (Richard Harter) (02/17/84)
One gets tired of this creationist vs evolution chatter. I suspect that it is rather obvious to all concerned that no one seriously advances creationism unless they are convinced beforehand that the Bible is literally true. I think it is also rather obvious that few of the contributors to this ongoing debate have any great knowledge of either geology, paleontology, biochemistry, or biology. The creationists trot their sleazy arguments and their opponents get hot under the collar and reply heatedly and largely irrelevently. Now that I have offended all parties, I mean to have a bit of fun by arguing in behalf of the creationists. PROPOSITION: Creationism is a valid and tenable scientific hypothesis. I shall define creationism as the hypothesis that most or all species of life and life on Earth itself were created by an external agency. I will not defend the proposition that the Earth was created a few thousand years ago; the evidence against that proposition is overwhelming. This may not be satisfactory to my fellow creationists but so be it. I shall take as granted that the Earth came into being about 4.5 billion years ago, that the Universe is some number of billions of years older, that life became present on Earth about 3.5 to 4 billion years ago, that it existed only in the form of prokaryotic cells (single celled lifeforms without nuclei) until about 1.5 billion years ago, that multi-cellular lifeforms first occurred about 600 million years ago, and that, in general, the major outlines of paleontology are correct. Let us begin by dividing the main proposition into three parts, to wit: (a) Abiogenesis is improbable. (b) Evolution has not been demonstrated. (c) Homo sapiens did not evolve. Abiogenesis is the proposition that life came into being spontaneously. The standard scenario that is presented is that about 4 billion years ago the Earth had a reducing atmosphere with signifigant bodies of water. Organic molecules were formed in the upper few feet of these bodies of water. Over time they formed a thin broth in which life eventually occurred. I have no quarrel with any of this except the final conclusion. I will note in passing that our knowledge of the state of the Earth in its early days is marginal and quite speculative. For this reason alone abiogenesis should be considered no more than a speculative hypothesis. My main point, however, is that a single cell, even a prokaryotic cell, is an enormously complicated thing and that the complications are essential to life. In particular they have a semi-permeable cell membrane, energy transport mechanisms, protein manufacturing facilities, and DNA reproductive templates. The cell membrane is essential; without it all of nutrients absorbed by and produced by the cell would drift off. Without energy transport and protein production the cell would starve and die. Without a means of reproduction the end would come less quickly, but just as surely. Now all of these elements must be present for the cell to exist at all. The critical weakness of the abiogenesis hypothesis is that all of the relevant mechanisms must come into being together. I could go into considerable detail. Let me leave the point with the observation that no convincing detailed scenario for abiogenesis has ever been presented. On to evolution. Currently there are upwards of a billion different species of life. The total number of fossils found is about one hundred million. The number of different species represented is considerably less. It is apparent that our knowledge of the history of life on this planet is somewhat less than complete. Let us grant that minor changes in species have been observed. Let us also grant that some major progressions in form, such as eohippus and the nautilus have been observed. Let us further grant that a number of species which were transitional in form have been found. Nonetheless I assert in very few instances have complete sequences of transitional forms been found. I suggest that the complete sequences that have been found have been variations in established forms. For example, eohippus becomes larger, the toes fuse together, etc. What we don't have are complete sequences where dinosaurs become birds. For the most part the paleontological record is broken by large gaps. This is to be expected; the ravages of millions of years are bound to be severe. The fact remains that the record is seriously incomplete. I do not deny that some evolution of form has occurred. I suggest, however, that it has not been demonstrated that major revolutions of form occurred. For example, mammals and birds have a high, stable body temperature. They have elaborate mechanisms, both behavioural and internal, for maintaining a constant body temperature. Reptiles and amphibians do not. The development of such mechanisms would have been a revolution in form. But did any such development occur? Can it be demonstrated that it could have occurred? In evolutionary biology, it is customary to investigate evolutionary scenarios. The general idea is that we look at an existing species in an existing ecological niche with some particular characteristic and look for circumstances in which primitive versions of the characteristic might have had a selective advantage. This works well enough as long as we are talking about a limited range of variation. Moreover, the selection mechanism is consistent with the known genetic diversity in natural species. When we turn to evolution in the large, however, we have the difficulty that scenarios are much more vague in detail. Moreover we do not know that the postulated genetic diversity is possible. That is, to go from A to B there must be a change in genetic material. However it seems very likely that there are limits to the ways in which genes can change. We neither know the limits or the requirements. Without this knowledge we don't really know what can be achieved by natural selection. On to the evolution of man. I will note simply that the fossil record is remarkably incomplete. We can go back 50,000 years and we find beings that, dressed in modern dress, could travel on a New York subway without attracting undue attention. Moreover we find evidence in their remains of the characteristic paraphenalia of humanity. The fossil record fails rapidly before that. I will also note that it has been often asserted but never shown that the differences in intelligence and cultural capability between human beings and their anthropoid "relatives" is one of quantity only. The unique character of human intelligence is a fact; it's nature and origin have not yet been explained. To summarize: so far we have shown that the evidence for the standard history of life as an evolu- tionary process beginning in abiogenesis is incomplete and not compelling. We now consider whether a valid alternative hypothesis can be framed. I suggest that it can, as follows: Let us postulate an agency or agencies, with the ability to manipulate and create genetic material, that has intervened from time to time during the history of Earth. Some possible interventions include introducing life itself and creating humanity. These interventions produced discontinuities in the history of life that had no significant probability of occuring spontaneously. This hypothesis is testable in principle; if it is found that discontinuities have been found then the hypothesis gains weight. Conversely, if no discon- tinuities are found or apparent ones are resolved then the hypothesis loses force. Finally, I would like to point out that it is not unscientific nor a violation of Occam's razor to admit the possibility that the intervening agency may be supernatural in character. TAKE THAT, YOU COMMIE PINKO, TAIL-GATING, WOMBAT LOVING EVOLUTIONISTS! In the tradition of the net, Richard Harter
y4101@dalcs.UUCP (Marcus Aurellius) (02/21/84)
Gee, you know? I think that the "supernatural" is by definition
unscientific! Right?
... Marcus Aurellius
Dalhousie University