Hi, guys! As much as I was hoping that this would be my last review post, I quickly realized that I couldn’t easily gloss over the evolution chapters and cover intelligent design in one post. Sorry about that! So, today I will be covering the next three chapters in Natasha Crain’s Keeping Your Kids on God’s Side, only one of which I’ll cover in any real detail. As I pointed out in my last post on creationism, Natasha once again neither endorses nor denies evolution through natural selection. However, I think there is an underlying reason for this. It is strictly my opinion that putting one’s endorsement behind one view or another in the creationism debate immediately ostracizes the other camps; and rest assured, that can be career suicide for many Christians wanting to make a name for themselves in the apologetic arena. Nevertheless, I think she does a good job of providing objective information throughout these next three chapters.
Chapter 37. What is evolution?
Chapter 38. What are the major pieces of evidence for evolution?
Chapter 39. What are the major challenges to evolution?
Natasha defines evolution as fundamentally meaning that “a species has undergone genetic change over time,” and she encourages her readers to understand that this concept is not controversial. It is the theory of evolution, the idea that all the lifeforms on earth share a common ancestor as a result of genetic variation and natural selection over approximately 4 billion years, that is disputed. Within evolution, Natasha also defines macroevolution as “large-scale changes above the species level,” while microevolution refers to “variation within species.” Although Natasha acknowledges that biologists do not recognize a functional difference between the two, macroevolution remains controversial among Christians.
In Chapter 38, Natasha lays out the evidence for macroevolution via the fossil record, demonstrating a progression from simple to complex organisms in addition to transitional fossils. Furthermore, the field of biogeography, the study of the geographic distribution of species, allows for accurate evolutionary predictions regarding species’ dispersion and location. Moreover, the evidence from vestigial traits, atavisms, and pseudogenes further solidifies evolutionary theory.
Moving on to Chapter 39, my personal point of interest, Natasha points out that although the evidence for the theory of evolution is compelling, it is “not without scientific challenges.” Yet, she notes that one would never know it, as outspoken atheists and the secular academic environment at large promote evolution as fact. I think this would be a good time to hash out why the theory of evolution is considered a fact. In an article titled “Is Evolution a Theory or a Fact?” the National Academy of Science explains why the theory of evolution is, in fact, a fact:
Now that we know that evolutionary theory is factual, let’s move on to its challenges.
1) Limited Transitional Fossils— Transitional fossils are what we might consider to be the in-between stage between an ancestral form and that of its descendants. What creationists want to see is a fossil that is the halfway point between two different species, and because this perfect representation isn’t seen in the fossil record, the theory is discarded. Why don’t we find these fossils, say the perfect intermediate state between a hippo and a whale? Because the fossil record does not denote a single line for any family of organisms but rather a series of branches upon other branches; and, of course, a transition like this would not happen in one rapid step. So, do transitional fossils exist? Yes, and there are many of them. For example, consider Tiktaalik, a fossilized fish from 375 million years ago that had not only gills and scales but also a flattened head like that of a crocodile and four unique fins that would have allowed it to prop itself up and support itself in shallow water like that of a tetrapod. This is exactly the type of fossil that Darwin’s theory accurately predicted for. (Just think…something that can actually make predictions, unlike creationism.) Given the sparseness of the overall fossil record, it is amazing that we have these intermediate fossils.
2) Cambrian Explosion— Skeptics of evolution also like to point to what is called the Cambrian explosion, a “sudden” uptick of phyla or different body forms that took place in the Cambrian period (541 million years ago to 485.4 mya). Creationists insist that the theory of evolution cannot explain the radiation of new phyla during this short time frame. It should be noted, however, that although 50 million years may be a short amount of time geologically speaking, it is not from a biological standpoint; it can, in fact, allow for a vast amount of speciation. Not only were phyla evolving prior to the Cambrian explosion, molecular evolution was also occurring. Thus, many of the organisms seen in this period are transitional forms, clearly linking them to their less complex predecessors. So, what caused the Cambrian explosion? There’s no simple answer to this question, but it has been reasoned that changes in sea levels resulted in increased erosion which then allowed for increased levels of oxygen, calcium, carbonates, and phosphates in the environment. These major changes in the atmosphere and environment from both a geological and chemical perspective allowed for new ecological niches that would influence natural selection. While the cause may be less definitive, it is clear that a gradual progression of life forms can be seen during this period, as would be expected in common ancestry via evolution. Or maybe Yahweh created these organisms out of nothing and then allowed them to die off in a sequence consistent with evolution.
3) Limited “Junk” DNA— In 2003, the Human Genome Project sequenced the full human genome and determined that only 2% of that sequence was functional, meaning that the other 98% was termed “junk DNA.” This would make sense if evolution over millions of years was allowing a build up of nonfunctional DNA. However, shortly afterwards, ENCODE was launched, a project seeking to understand the detailed workings of the genome. The results were a boon to creationists, as it was found that actually 80% of the genome has some biochemical function and therefore, according to creationists, must have been designed. Does functionality actually indicate design, though? Of course not. And what exactly is “some biochemical function”? If biochemical function is equated with biochemical activity, then yes, there was functionality. That does not, however, imply genetic usefulness, as creationists might have you assume. For a much more detailed look at this subject, I highly recommend Letters to Creationists excellent post, “Junk_DNA_Design.”
4) Harmful or Neutral Nature of Most Mutations— Can DNA mutations add new information in developing beneficial traits? The answer is a resounding YES. Both exon shuffling and gene duplication can add new genetic information. While exon shuffling plays a role in protein evolution, gene duplication allows for the duplicate or second copy of the gene to function properly if the first copy has been deleteriously affected by a mutation.
5) Challenges from Natural Selection— Natasha points out that even some evolutionists question the power of natural selection to solve all evolutionary problems, directing her readers to the website “The Third Way of Evolution.” As stated on their homepage, their goal is to allow for a “deeper and more complete exploration of all aspects of the evolutionary process.” They further note:
“It has come to our attention that THE THIRD WAY web site is wrongly being referenced by proponents of Intelligent Design and creationist ideas as support for their arguments. We intend to make it clear that the website and scientists listed on the web site do not support or subscribe to any proposals that resort to inscrutable divine forces or supernatural intervention, whether they are called Creationism, Intelligent Design, or anything else.”
6) Challenges from the Origin of Life— Natasha acknowledges that “evolutionary theory deals only with the manner in which life began. It doesn’t claim to explain the origin of the first life.” However, the question of how it all began is often coupled with evolution. Unsurprisingly, creationists find the concept of abiogenesis (the emergence of life from nonliving matter) unconvincing, especially given their theological presuppositions. Though several hypotheses exist, including the deep sea vent hypothesis, we may never have the full picture of how life first began. What we do know is that the diversity of life that we see today came about strictly through the natural processes of evolution. Why jump to the supernatural to explain the rest? Just because we don’t have all of the answers does not mean it is appropriate to throw a god into the mix, which is nothing more than an argument from ignorance.
**Next up…Intelligent Design (I really mean it this time!)