real life wrote:Without observation and proof, what do YOU have for evolution that differs greatly from mere assertion? Inference, circumstantial evidence ... both of which can be interpreted a number of ways.
The point is that when called upon to provide similar observation and proof for religious belief, the religionists do not provide. And as has been pointed out, there is verifiable, observable proof for natural selection, and it is not limited to "germs" as you choose to call them.
Quote:One of the best documented examples of natural selection in modern times is the English Peppered Moth, Biston betularia. Typically, this moth is whitish with black speckles and spots all over its wings. During the daytime, Peppered Moths are well-camouflaged as they rest on the speckled lichens on tree trunks. Occasionally a very few moths have a genetic mutation which causes them to be all black, so they are said to be melanistic. Black moths resting on light-colored, speckled lichens are not very well camouflaged, and so are easy prey for any moth-eating birds that happen by. Thus, these melanistic moths never get to reproduce and pass on their genes for black color. However, an interesting thing happened to these moths in the 1800s. With the Industrial Revolution, many factories and homes in British cities started burning coal, both for heat and to power all those newly-invented machines. Coal does not burn cleanly, and creates a lot of black soot and pollution. Since lichens are extremely sensitive to air pollution, this caused all the lichens on city trees to die. Also, as the soot settled out everywhere, this turned the tree trunks (and everything else) black. This enabled the occasional black moths to be well-camouflaged so they could live long enough to reproduce, while the "normal" speckled moths were gobbled up. Studies done in the earlier 1900s showed that while in the country, the speckled moths were still the predominant form, in the cities, they were almost non-existant. Nearly all the moths in the cities were the black form. It was evident to the researchers studying these moths that the black city moths were breeding primarily with other black city moths while speckled country moths were breeding primarily with other speckled country moths. Because of this, any new genetic mutations in one or the other of those populations would only be passed on within that population and not throughout the whole moth population. Additionally, because the city and country environments were different, there were different selective pressures on city vs. country moths that could potentially drive the evolution of these two populations of moths in different directions. The researchers pointed out that if this were to continue for a long enough time, the city and country moths could become so genetically different that they could no longer interbreed with each other, and thus would be considered distinct species. In this case, what actually happened is that the people of England decided they didn't like breathing and living in all that coal pollution, thus found ways to clean things up. As the air became cleaner, lichens started growing on city trees again, thus the direction of the selective pressure (birds) was once again in favor of the speckled moths. By now, English cities, as well as countrysides, all have speckled moths, and all are interbreeding at random, thus were not separated for long enough to develop into separate species.
Dr. H. B. D. Kettlewell, the main researcher who worked on Peppered Moths discovered the following:
Industrial melanism is characterized by rapid spread, increased genetic fitness, and occurrence among moths that depend on camouflage against a background of lichens, etc. for survival.
In most cases, melanism is inherited as a simple Mendelian dominant allele.
Work by earlier researchers indicated that melanistic forms of some species of moths went from less than 1% to around 95% of some urban populations within a period of 50 years, indicating around a 30% selective advantage over the light forms of those species.
This 30% selective advantage was a very unusual record high for wild populations of organisms.
By the time Kettlewell was doing his research, unpolluted areas of Scotland and England had almost 100% of the light, speckled form of the Peppered Moths, while urban areas and areas subject to drifting air pollution had 80% or more of the melanistic form.
Typically, under polluted conditions, the period from the initial black mutation(s) until 1% of the population is melanistic is relatively long. Once the 1% level is reached, the percentage of the melanistic allele in the population increases rapidly, until it reaches about 80 to 95%, at which point the increase in frequency slows.
Thus, with an assumed mutation rate of 1 in 1,000,000, a graph of numbers of melanistic moths in a population vs. time will typically yield an "s"-shaped (sigmoid) curve.
Even in areas where the melanistic form of the Peppered Moth has made up 95 to 99% of the population for over 60 years, the speckled form has never totally disappeared, resulting in a balanced polymorphism.
Industrial melanism is an indirect result of air pollution because the air pollution kills the lichens on the tree trunks and turns the trunks black. The soil around these trees is also affected (acid rain), and even the caterpillars of these moths must cope with eating leaves that are covered with "fallout" and/or which contain chemicals absorbed into the plant.
Bird predators on Peppered Moths include an European relative of chickadees and titmice called the Great Tit, a species of flycatcher, a nuthatch, the European Robin, and several other species of birds.
Kettlewell and N. Tinbergen working together showed that, in one non-polluted woodland, 164 speckled to 26 melanistic Peppered Moths were eaten by birds, while in a polluted woodland, 43 speckled and only 15 melanistic moths were eaten.
Kettlewell also conducted mark-and-release studies. In a polluted woodland, out of 137 speckled and 447 black Peppered Moths released, 27.5% of the black ones and only 13% of the speckled ones were recaptured. Keep in mind that if there is no selective pressure against either form, the null hypothesis would predict capture of equal percentages of the two forms released.
In an unpolluted woodland, out of 473 black and 496 speckled Peppered Moths released, 12.5% of the speckled were recaptured, as compared to only 6.3% of the black.
From these results, Kettlewell concluded that there was a definite "cryptic advantage" of the speckled moths against lichens and of the black moths against blackened tree trunks.
Kettlewell also conducted experiments which showed that the moths themselves can and do distinguish between a white and a black background and in most cases correctly choose a perching site that matches their coloration.
Reference: Kettlewell, H. B. D. 1961. The phenomenon of industrial melanism in Lepidoptera. Ann. Rev. of Entomol. 6: 245 - 262
If you read further at
the source page, you will also see that Mr. Kettlewell's findings have been disputed. Which is very much to the point. Evolution is a theory, it is not a dogmatic belief set. Evidence is examined in advance of assertion, and the theory is subject to replication, falsification and refutation. No such conditions apply to religious dogma. As do all of the religionists, you continually assert (and once again, it is assertion without evidence) that evolutionary theory is a dogmatic belief set equivalent to and no more valid than religious dogma. But no religionist ever questions their dogma, they do not test it by methods such as falsification or replication, and they accept no modification or refutation of their belief set. Scientific investigations, those which use evolutionary theory, and those for which it is not relevant, are not dogmatic, they rely implicitly and explicitly upon methods of falsification and replication--they are the antithesis of dogma. When a theory is successfully falsified, or fails of replication, it is either modified to more accurately describe observation and collected data, or it is discarded. The same can never be said of religious dogma.
Quote:I stated in no uncertain terms, as recently as 2 pages back:
real life wrote:I'm quite comfortable with the position that both creation and evolution are unobservable and unprovable by the empirical method. Hence neither are strictly scientific hypotheses. Both must be inferred from evidence available.
How 'bout you?
That you are comfortable in making an inaccurate, unsupported and unsupportable contention about evolutionary theory is hardly something which would convince anyone not gripped by dogmatic delusion. In the first place, there is no available evidence for the "inferences" of religious dogma. In the second place, natural selection
is observable, and it
has been observed.
Quote:So I don't see this as hypocrisy at all. Both are subject to the same limitation of unobservability and the inability to be verified thru replication; one because purportedly it happened long ago, and the other because purportedly it happened long ago.
This is a statement from authority, for which authority no one here has good reason to believe you can lay claim. This is once again mere assertion on your part, for which, predicably, you provide no evidence. Evolutionary theory does not deal in a series of static statements about past events. Crucial to evolutionary theory is the understanding that natural selection continues to occur, as does mutation, and that a theory of evolution as it is understood in the contemporary scientific community provides the best description for the evidence availabale.
Quote:You see a problem with this. I do not.
Certainly you don't--you have willfully misstated the character of evolutionary theory to make it fit your prejudices with regard to religious truth.
Quote:Germs developing immunity to diseases does not make them any thing other than germs.
Fish developing different characteristics does not make them any thing other than fish.
This is a willfully naïve statement on your part, and involves intentionally "dumbing down" one's understanding of the variety of species among any phylum of life forms.
Quote:If the cichlid analogy was valid, since they "evolved" differently based on their geographical separation-----
Are you prepared to assert (I certainly would not) that one race of mankind is more evolved and advanced than another, since they 'obviously' developed very different characteristics due to their geographical separation? Which race do you think is 'more evolved' and why?
Of course, not, that would be an incredibly stupid way to look at human evolution. The species
homo sapiens sapiens is alone in the world, all prior hominids (
australopithecus,
homo habilis,
neanderthalis, etc.) having either died off or evolved into later, more sophisticated hominid forms. Our species,
homo sapiens sapiens, has adapted to the world so well that we are now able to avoid, nullify or eliminate fatal population pressures. Furthermore, we have taken the wonderfully adaptive capacities of pattern recognition and memory out of our bodies and reposed them in universities, research institutions and libraries (all of which are thousands of years old). To even speak of different "races" of
homo sapiens sapiens is ludicrous, and either disingenous or ignorant, because we are a single species, capable of reproductive viability throughout the spectrum of populations. Geographical separation ceased to mean anything in human evolution past a point at which man became capable of manipulating his environment and making tools, garments and shelter.
I know you would like to reduce this argument to a few simplistic terms which will allow you to continue to contend that evolutionary theory and religious dogma are equivalent--but those of us who do not share your dogmatic conviction know better. All scientific theories are subject to challenge based upon method--no religious dogma ever admits of challenge, and brands those who do challenge ecclesiastic authority heretics, and at least hounds them, at the worst murders them. You have failed to make a case. You offer assertion, but no evidence.
