Originally Posted by slouiscar http:///forum/thread/384994/evolution/180#post_3376812
Darwin cited evidence for “micro-evolution.” The discovery of 14 different finches on the Galapagos, derived from a common ancestor, was the primary evidence cited for micro-evolution. The birds were each very different, yet closely related.
"From this observation, Darwin then extrapolated his explanation for the origin of life forms from a common ancestor, or “macro-evolution.” He used the evidence from the first half of his book on micro-evolution to suggest that the same mechanism could produce all life forms."
From this summary I take micro to be supported by facts... while macro is extrapolated, hypothesis... a proposed explanation for an observation. One that resulted in the ongoing grail quest for missing macro evolutionary links.
That aside, the purpose of my post was to ask the question, can evidence be found to prove that the introduction of new traits are the result of random gene mutation over eons? If there is no evidence are we then left to decide, is it faith in randomness, or faith in a higher power?
I think it is important that we speak the same language. It would help me if you could precisely define what you mean by "macroevolution", and how specifically it is different from "microevolution". Be aware that I will hold you to those definitions when I refute them. By macroevolution do you mean speciation? The appearance of a subspecies? The appearance of a completely new life form in one massive change? People want to know.
By the way, you have simplified Darwin's work to the point that it (your objection) is meaningless, and you have ignored 150 years of follow-up science that has failed to discredit Darwin in any major way, and with each scientific breakthrough has only supported his ideas.
One idea of Darwin's (if you can call it that) that has been revised by subsequent is the role of mutation. Darwin never proposed genetic mutation as the driver behind evolutionary change. Genetics was a pretty much unknown field, and the very concept of a gene would not become widely recognized for another 30-40 years. Darwin just spoke about change, and how natural selection would work on the diversity that appears in every generation. With the advent of the gene concept much focus was placed on random mutation. We now know that much of generational diversity is the result not of gene mutation, but of genetic rearrangement or duplication, resulting in existing genes acquiring either new functions or new regulatory mechanisms.