I'll meet your challenge but I do not expect you to comply with mine. Just what was Raup talking about...?
Well let's add some perspective by quoting a little more widely from the source material.
LEt's go all the way back to page 21.
We must distinguish between the fact of evolution -- defined as change in organisms over time -- and the explanation of this change. Darwin's contribution, through his theory of natural selection, was to suggest how the evolutionary change took place. The evidence we find in the geologic record is not nearly as compatible with darwinian natural selection as we would like it to be.
Right off the bat, Raup tries to draw a difference between the FACT of evolution and the explanation of how that change occurred. When he speaks of Darwin, he is speaking specifically of slow, gradual change.
Now on the next page he states
Now let me step back from the problem and very generally discuss natural selection and what we know about it. I think it is safe to say that we know for sure that natural selection, as a process, does work. There is a mountain of experimental and observational evidence, much of it predating genetics, which shows that natural selection as a biological process works.
Look at his own words. The source you choose to use in the paper you choose to quote. There is a "mountain" of evidence to support even gradual change through natural selection. Evolution through natural selection is a process that is shown to work.
On the next page.
Instead of finding the gradual unfolding of life, what geologists of Darwin's time, and geologists of the present day actually find is a highly uneven or jerky record; that is, species appear in the sequence very suddenly, show little or no change during their existence in the record, then abruptly go out of the record. and it is not always clear, in fact it's rarely clear, that the descendants were actually better adapted than their predecessors. In other words, biological improvement is hard to find.
Now we start getting to the crux of the matter. Raup supports puncutate equilibrium which says that most change is not gradual. Instead it is "highly uneven or jerky." While natural selection has "mountains" of data to show that it works, the data also show that it is far from the most common mechanism. This is in conflict with Darwin's own initial predictions. Darwin expected change to be dominated by the mechanism of natural selection resulting in gradual change across the board. THis is not what we find.
Your quote.
Well, we are now about 120 years after Darwin, and knowledge of the fossil record has been greatly expanded. ... Ironically, we have even fewer examples of evolutionary transition than we had in Darwin's time. By this I mean that some of the classic cases of Darwinian change in the fossil record, such as the evolution of the horse in North America, have had to be discarded or modified as a result of more detailed information.
First, could you find the full quote and give it for us? You always worry me with those ellipsis. I'd like to know what you are cutting out. It is normally important and not charitable to your position.
But, it should not start becoming clear what Raup was saying. It is Darwinian style, natural selection driven, gradual change that is not improving very quickly in quantity of data. Remember though, he has already said there is a "mountian" of evidence to support even this mechanism.
Also on the same page.
We must distinguish between the fact of evolution -- defined as change in organisms over time -- and the explanation of this change. Darwin's contribution, through his theory of natural selection, was to suggest how the evolutionary change took place. The evidence we find in the geologic record is not nearly as compatible with darwinian natural selection as we would like it to be.
Again, it is gradual change to which Raup is objecting here.
Finally, on the next page.
What appeared to be a nice progression when relatively few data were available now appears to be much more complex and much less gradualistic. So Darwin's problem has not been alleviated in the last 120 years and we still have a record which does show change but one which can hardly be look upon as the most reasonable consequence of natural selection.
This is your explanation. The original horse series, the one that was constrained by being assumed to be Dawinian in nature, the one that was assumed to follow a gradual process, had to be modified when more data was made available. When we had only a few fossils, it appeared to be a nice, smooth progression. When we found more data, the series was able to be seen as "complez" and not "gradualistic." Instead it was "highly uneven [and] jerky."
Context has once again betrayed you. Now meet my trap...uh challenge to you. I have answered you. Give me the same courtesy.
