[js1138]

However, for the second term, let me see if I understand what you are positing here: “Genetic drift” which is the appearance of purely random mutations operated upon by purely “arbitrary” selection mechanisms produces new species.

The answer is yes and no. Every species has to have individuals that are physically fit enough to survive. But if you look at parts of the world where the food supply is abundant, and predators few, guess what? You get birds with ten foot long tail feathers and such.

Sexual selection is an interesting phenomenon. It can't override factors that cause early death, but it can shape species as rapidly as human animal breeders. The underlying factors are sometimes a mystery, but when they are investigated in detail, it sometimes happens that the girls choosing their mates by plumage are actually picking healthier, stronger individuals.

[Lucky Dog]

Ladies and/or Gentlemen (Sorry, screen names do not lend themselves to positive identification)

Thank you for the time and effort you have expended in the dialog with me. I sincerely appreciate your contributions.

At this point in the discussion, enough posts (and confusion) have been generated, that it is helpful to me to summarize, collate and review. In my summarizations, for the sake of brevity, I have attempted to keep the level of detail to a minimum with no attribution of source. Consequently, I ask you to correct any misconceptions or errors on my part, again, keeping detail to only an essential minimum. Please note that the following summarizations do not necessarily represent my personal opinions. Rather, they are merely my honest attempt to restate what I have observed/read others on this thread and in other places state.

1. A theory posits a logical, consistent explanation of observed phenomena that is predictive and, thus, falsifiable, i.e., subject to disproof by detection of inconsistencies of predictions with different, or better/more detailed, observations. Theories are not facts as they can be discarded, (e.g., “humors” or “vapors” as the source of disease replaced by the micro organism/infection theory), or supplanted by “better,” or more comprehensive theories as a result of observation of new, conflicting phenomenon or better explanations/predictive abilities (e.g., Newtonian physics supplanted by relativistic theories and quantum mechanics). As a simple example, consider the following theory: Tornadoes are a function of thunderstorms. The presence of thunderstorms can be observed without tornadoes, but no tornado can be observed without the presence of a thunderstorm. Statistically, the data show a strong correlation. Therefore, the theory is consistent and strongly predictive (subject to falsification), albeit not very detailed.

2. The theory of evolution: the diversity of life currently observed (both in the fossil record and in vivo) originated with a single cell organism (with no comment on how such life originally came to exist). This organism underwent mutations at the DNA level resulting in changes of the organism, itself. The environment “chose” (“natural selection”) those new organisms that were best able to survive (“survival of the fittest”) and the remainder perished without passing along the genetic changes that were detrimental. This mutation/change/survival cycle continued with branches diverging and proliferating until, from the original, single celled organism there came to exist, the different species, genera, families, orders, classes, phyla, and kingdoms observed today. (I believe my summarization is correct to this point.)

3. Evolution as a theory lacks comprehensiveness in that it fails to explain why the phenomena that first created life fails to continue to operate, i.e., attempts to recreate “initial conditions’ have, thus far, failed to produce “new life.” Of course, this criticism is subject to the objection that initial conditions are impossible to recreate, most especially in the allowing the posited amount of time to pass for a successful observation. Nonetheless, this incompleteness subjects the theory of evolution to the objection that the originating phenomena (perhaps a deity or “intelligent designer”) may be continuing to operate and change living organisms outside of the postulated mechanism of evolution.

4. Evolution as a theory appears to be inconsistent with observed phenomena. Species can ostensibly come into, and go out of, existence on the basis of “genetic drift,” a phenomena apparently having absolutely nothing to do with the environmentally determined “survival of the fittest.” (This is the equivalent of saying that tornadoes naturally come into existence without the presence of thunder storms in the earlier example.) If one modifies the theory of evolution to allow the operation of an unpredictable, “arbitrary” selection factor, then the theory is no longer subject to falsification. Logically, if species can “drift” into existence without requiring “survival of the fittest,” then there is no reason that a species cannot “drift” into a new genus and, in turn, into a new family, new order, new class, new phyla, etc. If there is a postulated mechanism that limits this “drift,” then there is, logically, no reason that the same limiting mechanism would not limit changes due to natural selection or “survival of the fittest.”

5. Evolution as a theory appears to lack adequate predictive ability. Experiments with bacteria have failed to produce a new species. (Admittedly, contrary arguments can exist but must be muted by the failure among experts to agree on exactly what constitutes a species as well as the fuzzy definition of species.) Ignoring arguments over the definition of a species, short life cycles, large populations, and relatively simple genomes should allow the observation of the emergence of something that could be agreed upon as a new family, order, class or some such significant difference that could be agreed upon by all. However, to date, such has not been observed.

Again, before accusations of “troll-hood” are bandied about, please note that I have not necessarily claimed the above statements as my personal positions. Rather they are merely reworded (honestly, and hopefully, clarified and shortened) versions of what I have seen on this thread and other places. I have purposely avoided excessive detail and restricted the summaries only to major principles. I would ask that if I have erred in stating a major principle, that you offer corrections in the same briefly summarized fashion.