OBJECTIONS TO THE CAMBRIAN EXPLOSION EVIDENCE
Many scientists argue the lack of transitional forms in the fossil evidence is not an indictment against evolution, only an acknowledgment concerning the incompleteness of the fossil record. After Darwin published his findings paleontologists sympathetic to evolution made tremendous efforts to find the missing fossil evidence in the Precambrian strata. This Worldwide search for the evidence was met with incredible disappointment. The scientific community has had to formulate new explanations for the lack of fossil evidence.
One explanation is the reason transitional forms didn’t survive was because they were composed of soft body parts. They lacked shells and exoskeletons needed to survive the millions of years in the ground. Therefore, as we search the Precambrian strata we should not expect to find transitional forms because soft bodied organisms don’t leave fossil remains.
This hypothesis has problems. It is true soft bodied organisms do not preserve as well as hard bodied but there is enough evidence to put this explanation in jeopardy. Some of the Cambrian phyla identified are soft-bodied and we do have organisms with soft-bodies identified in the Precambrian strata. Plus the idea that soft-bodied ancestors are the precursors for hard-bodied Cambrian organisms seems to fall short on anatomical grounds. So many of the hard bodied organisms depend on their shells for protection and would never have survived without them. Instead what we should see in the fossil record, if Neo-Darwinian evolution or punctuated equilibrium is true, is a series of hard-bodied transitional organisms in the Precambrian strata leading up to the Cambrian. The fossil evidence does not support either of these theories.
Another explanation is the early transitional organisms were too tiny to be preserved. This seems plausible but the problem arises with the existence of microfossils found imbedded carbonaceous cherts. They have been estimated to be between 3.3 billion to 3.5 billion years old. Species of single-celled algae and the appearance of cells in formations that are far older make a case that while investigating the Cambrian strata we should have found the Precambrian precursors somewhere in the over 500 million years of sedimentary strata below the Cambrian. With the existence of smaller and much older fossils in other locations, this explanation seems to fall short. Overall, the two arguments for the absence of transitional forms based on soft-bodied and small sized organisms, is countered by the lack of fossil evidence in the Precambrian and Cambrian strata. There doesn’t seem to be a viable hypothesis for explaining the lack of transitional forms.
An additional attempt has been to demonstrate that the existing fossil remains in the Precambrian strata were sufficient evidence as precursors to the Cambrian phyla. In particular, scientists point to late Precambrian (Vendian) multicellular organisms as representatives of the transitional forms to the Cambrian animals. Studies summit the date for the first appearance of the Vendian fossils at about 565-570 million years ago and their last appearance at the beginning of the Cambrian geological time period. There are four types of Vendian fossils and are mostly soft-bodied and identifiable by the human eye. On paper this seems to be a possible argument for what we see in the later strata. However, there are some problems.
First, what we find in the pre-Cambrian fossil remains doesn’t bear resemblance in body structure with the Cambrian fossils. Examples include the Ediacaran organisms, such as Dickinsonia and Springinna, which do not have eyes, mouths, or anuses. Many paleontologists doubt these organisms belong in the animal kingdom. Second, the Precambrian strata only documents at most 3 or 4 phyla as compared to the 19 or more phyla attributed to the Cambrian strata. Thus taken as a whole the Precambrian fossils are inadequate to explain the vast array of novel body structures that exist in this strata. Not only does this evidence work against Neo-Darwinian evolution and punctuated equilibrium but also the fact that the precursors to the Precambrian organisms are questionable transitional forms. Both Neo-Darwinian evolution and punctuated equilibrium need evidence of transitional forms to be adequate explanations. Upon close inspection those organisms that do exist seem to fall short of meeting that standard. Neither theory can explain the existence of organisms that suddenly appear in the Cambrian strata with novel body-plans.
The goal of these posts was to make the case that neither Neo-Darwinian evolution nor punctuated equilibrium could explain the fossil evidence found in the Cambrian strata. Neo-Darwin evolution and punctuated equilibrium needed to demonstrate: 1) A gradual move from simple to complex with multiple transitional forms leading to new phylum-level body plans; 2) we should have found small-scale morphological diversity coming before large-scale morphological disparity; 3) we should have observed a steady increase in the number of phyla over time (accounting for extinctions along the way). The evidence instead demonstrates all three key criteria to be false. Plus, I answered two additional objections. 1) the fossil evidence is incomplete because the soft-bodied fossils don’t preserve or they were too small to leave evidence and, 2) the existing fossils in the Precambrian strata are the precursors to the Cambrian animals. My conclusion is neither Neo-Darwinian evolution nor does punctuated equilibrium adequately explain the fossil evidence of the Cambrian strata.
 John Angus Campbell and Stephen Meyer, eds., Darwinism, Design, and Public Education (MichiganStateUniversity Press, 2003) pg. 357
 Ibid. pg. 360
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