Last comments I can really make regarding Tiktaalik and transitional fossils:
1. It is not illogical to suppose that morphology is an indication of evolution.
One cannot simply take morphology as an indicator. That would indicate thylacines were more closely related to wolves than to kangaroos. Rather, one has to look for homologies, and if possible, get genetic data to support it.
2. It is not illogical to suppose that the position of fossils in the fossil record is an indication of evolution.
It is, as YE creationist Kurt Wise says, "very good evidence for macroevolutionary theory."
In the case of Tiktaalik (or we might even consider Archaeopteryx, Pakicetus, or Pezosiren portelli... any of the more widely famed 'transitional fossils), points 1 and 2 are great examples of corroborating evidence to the claim (the claim is "macro" evolution... the arrival of new and drastically different life forms).
But they aren't drastically different. The very existence of those transitional series shows rather a history of relatively small changes. For example, the movement of the blowhole in whales shows a history of gradual changes.
But are these claims enough? They might certainly have been enough 100 years ago.
Today; however, technology has been advanced forward and [relatively] simplistic assumptions like points 1 and 2 do not really prove evolution in and of themselves.
Scientists don't really use mere morphology. Homologies (like bones of flippers, legs, and wings in mammals) are much more reliable. Which is why scientists use them, rather than "morphology."
To find out if points 1 and 2 mean what they are claimed to mean, scientists need to be able to go under the hood and understand the 'drive system' of evolution. Since the 1950's this has come more into light with the discovery of DNA.
Good point. When the function and structure of DNA was discovered, scientists realized that it could be used to test conclusions made on homology and paleontological data. It turned out that DNA analyses gave the same phylogenies for evolution that other data did, to a very good precision. It verified earlier work.
Since this discovery, scientists have sought to prove that in fact this drive system can and does result in evolution.
Darwin had doubt about evolution because the fossil record (what was known at the time), did not corroborate the slow, gradualistic change that would have occurred if evolution were true.
No. He concluded that the fossil record in his time was very incomplete,and predicted that as time went on, more and more of the fossil record would confirm his theory. His prediction has been verified.
In my lifetime, there have been many, many gaps in fossil record filled in:
Whales with legs.
Dinosaurs with feathers
Transitionals between humans and other apes
Snakes with legs
Transitionals between cockroaches and termites
Transistionals between wasps and ants
Transistionals between salamanders and frogs
Transitionals between turtles and other anapsids
(very long list)
Over time this led to the development of the artifact hypothesis--that the fossil record was incomplete or scientists just had not yet discovered enough about the fossil record.
In the past 150 years since then, most of the gaps between major forms now have transitional forms. If you doubt this, name any two major groups, said to be evolutionarily connected, and we'll see if I can find a transitional. Which two would you like?
Further, the Cambrian explosion is not the only "explosion" - there are some 17 or so abrupt appearances of new and distinct life forms throughout the record.
That story no longer works, since we have numerous examples of complex organisms in the Precambrian, some of which show the supposedly "sudden" forms of the Cambrian. Recently, scientists were able to confirm at least some of them are animals, demonstrating that the Ediacaran fauna let to the Cambrian radiation of forms, which appears to be mostly due to the evolution of fully-covering exoskeletons.
Now if the response to this is, "So what NobleMouse, the arguments here don't prove that evolution didn't happen." Well then let's go back under the hood, and the work that has been done by scientists in the creation / ID / non-religious camps.
As was determined by federal courts, ID is a religious doctrine, said by the people who invented it, to have the objective of proving God. The infamous "wedge document", published by the Discovery Institute admits this. However, here's what a prominent fellow of the Institute says:
t is important to emphasize at the outset that the argument presented here is entirely consistent with the basic naturalistic assumption of modern science--that the cosmos is a seamless unity which can be comprehended in its entirety by human reason and in which all phenomena, including life and evolution and the origin of man, are ultimately explicable in terms of natural processes. This is an assumption which is entirely opposed to that of the so-called "special creationist school." According to special creationism, living organisms are not natural forms, whose origin and design were built into the laws of nature from the beginning, but rather contingent forms analogous in essence to human artifacts, the result of a series of supernatural acts, involving God's direct intervention in the course of nature, each of which involved the suspension of natural law. Contrary to the creationist position, the whole argument presented here is critically dependent on the presumption of the unbroken continuity of the organic world--that is, on the reality of organic evolution and on the presumption that all living organisms on earth are natural forms in the profoundest sense of the word, no less natural than salt crystals, atoms, waterfalls, or galaxies.
In large measure, therefore, the teleological argument presented here and the special creationist worldview are mutually exclusive accounts of the world. In the last analysis, evidence for one is evidence against the other. Put simply, the more convincing is the evidence for believing that the world is prefabricated to the end of life, that the design is built into the laws of nature, the less credible becomes the special creationist worldview.
Michael Denton, Nature's Destiny
Are you sure that this supports your beliefs?
The creation and ID camps for sure, and even some from the non-religious have concluded that there is no evidence that random mutation and natural selection produce new information on the order that produces anything other than the subtle variations that are observable in nature and demonstrable through experimentation.
Perhaps you don't know how information is calculated. In fact, every new mutation adds information to a population. But information does not have to increase in evolution. Sometimes, it decreases, and almost always does during speciation, which usually involves isolation of a smaller and less genetically-diverse sub-population.
This is why leading biological scientists had met at the Royal Society in London calling for new mechanisms to support evolution--the claimed 'drive system' is broken.
Most of those "new mechanisms", such as niche construction, were already known in Darwin's time. His last research was on the way that earthworms affect their environment. The argument was never whether or not those were part of the random mutation/natural selection process; it was over their relative importance.
Evolutionary theory has greatly expanded our understanding of the processes by which new species and higher taxa evolve. Indeed, most creationist organizations now admit the fact of speciation. Some admit the evolution of new genera and familes of organisms as well.
And remember, "information" doesn't have to increase in such diversity; indeed, it often decreases during speciation. This is how "founder effect" is observed to function.
