^{http://www.amnh.org/exhibitions/darwin/idea/treelg.php}

Once Strobel and Wells try to make their case for a supernatural origin by trying to discredit the natural hypotheses rather than presenting any evidence for their case they take on Darwin's tree of life. It is an exercise in the obvious to say that Darwin's tree of life is no longer an adequate representation and it is not considered so by biologists. However, Wells and Strobel go well beyond this and try to make it sound like creatures have appeared ex nihilo. Let's take a look at his specific claims.

Wells says “a key aspect of his theory was that natural selection would act, in his own words, 'slowly by accumulating slight, successive variations' and that 'no great or sudden modifications' were possible." Was Darwin right that evolution depended on accumulating slight, successive variations? For the most part he was wrong. Most animals seem to evolve by long periods of stasis followed by rapid change, a process called punctuated equilibrium. This is supported by genetics because sudden changes can occur with mechanisms such as gene duplication or gene deletion and selective pressures [Science 14 February 1986 231: 672-673, Science 21 June 1996 272: 1802-1804]. He was not totally wrong, however, as some species do seem to evolve gradually. An example is the microfossils. These have evolved so consistently that their change throughout the layers has been used as an oil finding technique [http://www.ucmp.berkeley.edu/fosrec/ONeill.html]. You also need to consider what is meant by the word "quickly" when used to look at evolution, time is relative and can differ in relation to different processes. For instance, a day would be much longer for a fruit fly than for redwood.

Wells uses this relativity of time with his primary example when he says "the Cambrian was a geological period that we think began a little more than 540 million years ago. The Cambrian explosion has been called the 'Biological Big Bang' because it gave rise to the sudden appearance of most of the major animal phyla that are still alive today, as well as some that are extinct." What Wells fails to tell the Strobel and the reader is that this 'explosion' occurred over a time period that lasted tens of millions of years and that there have been numerous soft bodied animals that were discovered prior to this time. It be true that there are less examples from this time, probably because hard-bodied animals to fossilize more easily [which is the same reason that we find many more fossilized bones than soft tissues]. Even though there are fewer examples, there are still many fossils from the Ediacaran period. There are over 2000 individual fossils from the Ediacaran period representing over 30 genera and 50 different species [Evolution: What the Fossils Say and Why it Matters. 2007]. Essentially, Wells is claiming that tens of millions of years, a relatively short time on a geologic timescale, is rapid on a biological timescale. To put that into perspective, modern humans [Homo sapiens] have existed for about two hundred thousand years and the average human lifespan is slightly over seventy-years or 0.0000000000003 the duration of the Cambrian explosion.

 

Wells continues to espouse the notion that the Cambrian explosion was a rapid change on a biological time scale rather than on a geological time scale and then says one of the less credible statements up to this point. Wells states “some paleontologists, even though they may think Darwin’s overall theory is correct, call it a lawn rather than a tree…” I’ve never heard a scientist say this, ever. Most scientists make the analogy of a bush due to the numerous branches and dead ends.

 

From here, Strobel goes into a feigned support of evolution and Darwin. He states “Or perhaps…the organisms that existed prior to the Biological Big Bang were too small or their bodies to soft to have left any trace in the fossil record.” Wells points out that there are microfossils and even points out soft bodied Cambrian fossils. He continues to avoid mentioning the many Ediacaran fossils that exist. One particular example is the Ediacaran benthic, Kimberella [related to starfish, clams, whelks, etc.] There are over 35 examples of this relative to the mollusk that lived 555-558 million years ago [Nature 388, 868-871. 28 August 1997].

^{Kimberella, Nature 388, 1997}

 

After falsely claiming that there are no pre-Cambrian fossils, which although he doesn’t specify, I think he meant animal fossils, Wells moves to comparative genomics. A succinct explanation of both the fossil record and DNA clocks was in the 20 June 2007 edition of Nature, p894.

 

 “That molecular dates are a little earlier is to be expected. DNA should record the moment that a lineage split, but the imperfections of the fossil record mean that the first preserved post-split organisms will date from later on. And there are some groups — such as the microscopic, soft-bodied animals that make up about half the extant animal phyla — that have no fossil record at all…DNA clocks have their own problems, which can cause overestimates of the age of evolutionary splits. Different genes can evolve at different rates, and the calibration of DNA clocks must be handled carefully. A calibration that involves a slowly evolving lineage can throw a whole tree off.”

 

In conclusion, the claims made by Wells don’t stand up to scrutiny. He still is not providing any evidence for his creator claim but is merely attacking science.  His claim that the Cambrian explosion was a quick occurrence is just plain wrong on a biological scale, his claim that there were no fossils prior to the ‘explosion’ is not true either.