There's a basic problem with Darwinian evolution as it stands today. Its been 'preached' as though it were fact yet with so many of its variations comes the revelation that there really is a vast chasm of disagreement within the scientific community when it comes to origins.
For example; one of those 'nuances' that I refer to are the opinions held by many scientists that life on this planet may have been planted here rather than forming naturally over 4.5 billion years.
The Search for Extra Terrestrial Intelligence (SETI) vigil for ET may sound strange if you haven't heard of it but one of its purposes is to find out how life may have originated on the earth.
"In a very real sense this search for extraterrestrial intelligence is a search for a cosmic context for mankind, a search for who we are, where we have come from, and what possibilities there are for our future." - Carl Sagan
Just a few miles up the road from me (Hat Creek) is a radio telescope array--listening for the elusive ET. The SETI 'syndrome' began in 1960 when a scientist calculated the possibilities of how many planets may exist in the universe supporting intelligent life.
The origin of life on planet earth remains a mystery because as one scientist said,
"We don't really know how life originated on this planet. There have been a variety of experiments that tell us some possible roads, but we remain in substantial ignorance. That said, I think what we're looking for is some kind of molecule that is simple enough that it can be made by physical processes on the young Earth, yet complicated enough that it can take charge of making more of itself. That, I think, is the moment when we cross that great divide and start moving toward something that most people would recognize as living." - Paleontologist Andrew Knoll, professor of biology at Harvard and author of Life on a Young Planet: The First Three Billion Years of Life.
For more eye opening stuff on SETI see what Michael Crichton said in a lecture at the California Institute of Technology in Pasadena, CA. (Aliens Cause Global Warming)
One of the other nuances is the answer to the question: What really killed the dinosaurs?
From the 1980's scientists thought they'd found the answer. They called it the 'impact theory.'
The theory says a "10km-wide meteorite had smashed into the Yucatan peninsula in Mexico, causing worldwide forest fires, tsunamis several kilometers high, and an 'impact winter' - in which dust blocked out the sun for months or years. It was thought that the dinosaurs were blasted, roasted and frozen to death, in that order."*
Today that theory is being challenged as new evidence is uncovered. Scientists have uncovered plenty of evidence that there was not one, but a number of extinction level events (ELE), even larger than the impact that created the KT boundary. Each would have interrupted the billions of years many scientists claimed would be required for a traditional evolution model proposed so far.
Dr. Knoll summed up the scientific view of origins when he said, "…we remain in substantial ignorance."
Despite the discord within the ranks of evolutionists, they present a united front when it comes to allowing the viable evidence for the theory Intelligent Design to even be considered.
I guess that free thinking is limited to those who completely close their minds to the possibility of a creator--yet isn't it they who say Christians are closed minded? I will close with what some evolutionists **themselves say about the fossil record:
"Despite the bright promise that paleontology provides a means of 'seeing' evolution, it has presented some nasty difficulties for evolutionists, the most notorious of which is the presence of 'gaps' in the fossil record. Evolution requires intermediate forms between species and paleontology does not provide them ..." - David B. Kitts, PhD (Zoology) Head Curator, Dept of Geology, Stoval Museum Evolution, vol 28, Sep 1974, p 467
"The curious thing is that there is a consistency about the fossilgaps; the fossils are missing in all the important places." Francis Hitching The Neck of the Giraffe or Where Darwin Went Wrong Penguin Books, 1982, p.19
"The absence of fossil evidence for intermediary stages between major transitions in organic design, indeed our inability, even in our imagination, to construct functional intermediates in many cases, has been a persistent and nagging problem for gradualistic accounts of evolution." Stephen Jay Gould, Prof of Geology and Paleontology, Harvard University "Is a new general theory of evolution emerging?" Paleobiology, vol 6, January 1980, p. 127
"...Yet Gould and the American Museum people are hard to contradict when they say there are no transitional fossils ... I will lay it on the line, there is not one such fossil for which one could make a watertight argument." Dr. Colin Patterson, Senior Paleontologist, British Museum of Natural History, London As quoted by: L. D. Sunderland Darwin's Enigma: Fossils and Other Problems 4th edition, Master Books, 1988, p. 89
**Thanks to Ted Holden for the quotes