Wednesday, December 16, 2009

Part 5: The Cambrian Explosion

Introduction
Part 1
Part 2
Part 3
Part 4

Continuing with Dr. Jay Wile and Marilyn Durnell...

Word count: 1,192
Estimated reading time: 6-9 minutes

Before we leave our discussion of the fossil record, we have to mention probably the greatest problem that faces macroevolutionists today. The problem exists as a result of some fossils that were “rediscovered” in the mid-1980s, and based on those fossils, we know that at least the bottom portion of the geological column as presented in Figure 9.2 (and all introductory biology and geology textbooks to our knowledge) is incorrect. You see, as presented in Figure 9.2, the geological column is used to give the impression that the fossil record indicates that only the “simplest” multicellular life existed in the years represented by the Cambrian rock (570-500 million years ago), and then through the years represented by the Ordovician rock (500-435 million years ago), the life got more complex. This supposedly continued through to the times represented by the Silurian rock (410-435 million years ago) as well as the time represented by Devonian rock (360-410 million years ago). As a result, the diverse life that we see in the oceans did not fully evolve until about 400 million years ago. Now remember, all of these numbers for how many millions of years ago these things happened are based on a lot of assumptions, and we don't have time to go into those assumptions. However, we are discussing how macroevolutionists interpret the geological column, and this is how they do it.

Based on the “rediscovery” we mentioned earlier, we now know that the macroevolutionists' view of the lower layers of the geological column is simply false. What do we mean by “rediscovery?” Well, in the early 1900s, Charles Walcott (a paleontologist) discovered a lot of fossils in a layer of Cambrian rock called the “Burgess Shale.” However, these fossils were not what Walcott expected. Remember, according to the geological column, only the “simplest” of multicellular life was supposed to have existed in the times represented by Cambrian rock. However, Walcott found thousands of fossils of very complex life. In fact, by the time the collection was complete, Walcott had found representatives from every major animal phylum that exists in our classification scheme (see Figure 9.5 below).

What did this stunning discovery mean? It meant that the bottom of the geological column as presented in textbooks (still to this day) is wrong. Walcott found fossils of the “simple” animals that were supposed to be in Cambrian rock, but he also found thousands of examples of animals that were too complex to have evolved in the short time represented by Cambrian rock. According to the geological column, some of these animals were supposed to have formed much, much later, in the times represented by Silurian and Devonian rock. Why in the world were these complex fossils found in Cambrian rock? Walcott had no real answer to that question.

In other words, Walcott had discovered something revolutionary! This was a find that would radically alter the scientific world's understanding of the geological column. What, then, do you think he did? What would you do if you discovered something so revolutionary? I would think that you would publicize it so that the whole world would see it. That's not what Walcott did, however. He wrote a few modest articles in an extremely obscure scientific journal (Smithsonian Miscellaneous Collection), and then he reburied the fossils in his laboratory drawers, and he never mentioned them again. It would be 80 years before the fossils were “rediscovered” and their importance understood.

What is their importance? As we mentioned, they tell us that the first few layers of the geological column as presented in the geological column are simply false. After all, the geological column pictures the animals in the “simple” phyla evolving into the animals of the more complex phyla over a period of about 170 million years (from Cambrian rock to somewhere in the middle of Devonian rock). This, however, is not what the fossils say. The fossils discovered by Walcott (more than 60,000 in all, some of which are reconstructed in the figure below) and those discovered later by others tell us that all of the major animal phyla can be found in Cambrian rock.

These fossils lead to a serious problem for macroevolution. All macroevolutionists agree that macroevolution takes a long time. No one presently understands how such a huge amount of evolution could have taken place in the relatively “short” time supposedly represented by Cambrian rock. Even if the currently-assumed ages for Cambrian rock are correct, it took “only” 70 million years for evolution to go from the simplest animal phyla to the most complex animal phyla. At present, no one understands how this could have happened in the context of macroevolution. In fact, the problem is so well-known in the field of paleontology, it has a name. It is called the Cambrian Explosion, which refers to the fact that there seems to have been an “explosion” of life in Cambrian times.

Not only is the “short” time a problem for macroevolution, but the fossils themselves present a real problem as well. Even though the fact that there are no intermediate links in the fossil record is a well-known problem for macroevolution, the problem is much more dramatic in Cambrian rock. After all, a huge amount of macroevolution had to have occurred in the time represented by Cambrian rock, but there is just no evidence for it. There aren't even possible transitional forms like Archaeopteryx or Australopithecus. In fact, the creatures that are fossilized in Cambrian rock just appear there suddenly, exactly as you would expect if each of these creatures was simply made by God.

One of the most honest summaries of the problem that the Cambrian Explosion presents to macroevolution is given by prominent macroevolutionist Richard Dawkins:
(block quote) It is as though they [fossils] were just planted there, without any evolutionary history. Needless to say this appearance of sudden planting has delighted creationists...Both schools of thought (Punctuationists and Gradualists) despise so-called scientific creationists equally, and both agree that the major gaps are real, that they are true imperfections in the fossil record. The only alternative explanation of the sudden appearance of so many complex animal types in the Cambrian era is divine creation and (we) both reject this alternative. (Richard Dawkins, The Blind Watchmaker, [New York, NY: W.W. Norton & Company, 1996], 229-230) (block quote)

Notice how honest Dr. Dawkins is in this quote. He tells us that the fossils seem to have just “appeared” there, without any evidence of evolution whatsoever. He says that both schools of macroevolutionists (we will discuss what “Punctuationists” and “Gradualists” are later) agree that even though the fossils seem to indicate that the creatures were created divinely, they must reject that notion, and they must therefore assume that the appearance of “planting” is just due to imperfections in the fossil record. What does he mean by “imperfections?” He means that the intermediate links did, indeed, exist, but they just happened to have not been fossilized. This is what you are forced to believe if you look at the fossil record and reject the most obvious conclusion that it presents: that the organisms preserved there were divinely created.

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