First about the flatfish to Helix -- I don't have any trouble with God choosing to create what He created. I rather imagine the flatfish were part of an original population of their own. I have not read in the Commandments or anywhere something saying "Thou shalt be symmetrical"! Personally, I rather enjoy that the world is not black and white, but colorful, and that there are not just a few types of animals and plants, but many. I enjoy the variety we see, no matter whether it was a matter of variation or creation.

Now, about extinctions and fossilizations. It seems there may have been a little confusion about the two in some of the posts above. First of all, I think Helix is right about the burial factor. Local is just fine, and, in fact, I think that is what happened. After Noah's Flood the world would have been in a bit of a turmoil geologically for some time. Local areas of earth movements and flooding and land or mudslides would have provided what little we know of the necessary conditions.

The extinctions are different, however. We show three times of massive extinction events in the geologic record. The last, which seems to have affected the dinosaurs so much, was about 65 million atomic years ago and definitely involved a meteorite hit, or several. I have always had a question about Iceland sitting right on top of the Atlantic Rift. When you look at a topographical map, it simply LOOKS like it may have been initiated by a rather large hit. We then seem to have a string of craters going southwest from there, including in the Caribbean, across part of Canada and into Arizona -- these we can see. How many others, we don't know. But they correspond to the iridium layer in the geologic record (Barry's asleep right now and this is his area of expertise, so I might have misidentified some as being in this particular layer, but the trend is there), and that corresponds to the last we see of most of the dinosaurs.

Were they fossilized by the impact itself? No. That would not have been possible. But the impact MUST have set off enough geologic activity to have caused tsunamis and subsequent flooding and slides -- and THAT very well might have contributed to fossilization.

Don't forget, as well, that there are different kinds of fossils. One is a type you can easily make yourself -- an imprint fossil. We used to do it with jello when I was teaching! Get the stuff about 3/4 jelled, put a leaf on top, finish jelling, and then pour another layer of a different colored jello on top, which is already half jelled.

When both are jelled, tease the two layers apart and you have a perfect 'fossil' imprint of a leaf! We also understand mineral accretion, where we have something like the orange or miner's hat in Australia, lost in caves, which were quickly (about a hundred years) pretty much covered with minerals from the dripping waters in the caves.

What we have NOT seen and cannot seem to replicate is the replacement of biologic substance with minerals, such as we find in fossil bones or petrified trees.

And until we can get a handle on this type of fossilization, the 'when' of it as related to any catastrophe, cannot really be determined...
As close as we can get is the atomic age of the strata in which the fossil is found -- and even that can be in question -- big question -- if the dating involves argon (because it migrates so rapidly).