As Thomas Frank points out in What's the Matter With Kansas?, the debate about evolution is central to the culture wars. And like most Christian conservatives, Rick Santorum has strong doubts about evolution. He believes that we should "teach the controversy" about evolution, which means that students in biology should be taught that the theory of evolution is controversial and that there are many differing viewpoints about the topic. Indeed, as a Senator he authored the Santorum Amendment, which was originally attached to the No Child Left Behind bill, but subsequently was removed.
Although I myself am an academic and a humanist, I actually agree with Rick Santorum on this issue. The controversy should be taught and understood by all educated Americans because it lies at the very heart of the deepest ideological disagreements of our nation. An important point of difference I have with Santorum is that I think the controversy should be taught in social studies and political science classes, rather than biology. This is because the real controversy is in the domain of politics and the ideological direction of the country, not in biological science.
The point of this rather lengthy post is to help frame the controversy surrounding evolution, understand what the major perspectives are, and what about the controversy should be taught. Specifically, I want to help folks who have not researched the controversy to get clear about what exactly is meant by evolution (and the various meanings of the term), understand what is controversial and why, and understand what are reasonable and unreasonable positions to take. In my experience, many individuals from 'blue states' have no idea what the controversy is about nor do they realize how many people in America question evolution. I am especially writing this for them, as it is, in my opinion, essential that every informed American be clear about this issue.
A good place to start is to get clear on the meaning of the term evolution. In its broadest, most generic sense, evolution means change, growth and development. Everyone agrees that there has been some changes across the across the (recent) generations. That bacteria become more resistant to antibiotics over time is not disputed by anyone. In the political debates about evolution, anti-evolutionists often refer to this as 'micro-evolution', to separate it from 'macro-evolution'. The second meaning of the term evolution refers to decent with modification, which refers to the belief that all the life on earth emerged from a common ancestor. This is what anti-evolutionists sometimes refer to as 'macro-evolution' (or molecules-to-man evolution) and dispute that this has happened at all. The third meaning of the term evolution refers more directly to Darwin's theory of natural selection. The essence of Darwin's theory is that biological complexity and diversity can (and has) emerged as a function of differential rates of survival and reproduction. Specifically, the theory posits that organisms vary in their capacity to solve problems related to survival and reproduction and that those characteristics are passed down through the generations. Mainstream biology sees natural selection as the primary causal mechanism in evolution. It is also worth noting here that 'the modern evolutionary synthesis' refers to Darwin's theory of natural selection merged with genetics (more on this below). The final meaning of the term evolution (as when creationists refer to 'evolutionists') refers to a naturalistic worldview that is explicitly rejecting of the existence of God. Given these varied meanings, when someone says that they do or do not believe in evolution, it is crucial to be clear about how they are using the term.
Major Worldviews in America Today
Now let's consider the various worldviews prominent in America today, which are related to the different definitions of evolution. There are basically five positions taken regarding beliefs about the intersection of science, religion, and the concept of evolution. They are: 1) Young Earth Creationism; 2) Intelligent Design; 3) Theistic Evolution; 4) Agnosticism; and 5) Exclusionary Naturalism.
Young Earth Creationism (YEC) in America is generally grounded in Christian Fundamentalism and the belief that the Bible is revelation from God and is literally true. If you start with that premise, Y.E. Creationists argue it is clear, based on the narrative in Genesis, that God created man, beasts, plants, etc. all at about the same time (the six day narrative). They argue that a straightforward reading of the Bible clearly indicates that life has existed, not for millions or billions of years, but for thousands of years. Hence the term 'young earth'. Young Earth Creationists (YEC) themselves debate whether there is good science to support the belief in the young earth or whether the belief in a young earth should simply flow from one's faith that the Bible is true. The founder of the creation science position, Henry Morris, argued that all the science pointing to an ancient earth was flawed and that phenomena like the Grand Canyon can be scientifically explained by the Great Flood (yes, the flood that led Noah to build his arc, which is believed by fundamentalists to have really happened). In contrast, Ken Ham, the founder of the Answers in Genesis Ministry believes that we should be led not by science, but by faith in the foundational truth of the Bible. Regardless of this difference, YEC is the most rejecting of mainstream science. Not only do YE Creationists reject evolutionary biology, but they must also reject mainstream cosmology, geology, paleontology, archeology, and all the other scientific disciplines that point to an earth and universe that has existed for billions of years.
The second group, those who support Intelligent Design (ID), generally are not opposed to an ancient earth. Instead, they largely make two claims. First, IDers argue that Darwin's theory of natural selection cannot account for all biological complexity and go to great lengths to argue that Darwin's theory of natural selection has been oversold (see, for example, blogs here and here). The second claim they make is that there is evidence for an intelligent designer. Michael Behe, for example, argued that there was irreducible complexity in the mechanisms of the cell that could only have arisen via a purposeful designer (most but not all IDers believe the designer is a Christian God). Some IDers are more passive, and arrive at their claim in a belief in an intelligent designer because they are certain that Darwin's theory fails. Think about it this way...if you stumbled across a watch in the desert, it would follow that, based on all the intricate complexity in the watch it did not arise by chance but instead must have been designed by some intelligent entity. Given that organisms are much more complex than watches, IDers argue the same logic applies (which is a reasonable position if you agree that Darwinism can't do the trick).
The third approach is Theistic Evolution. Theistic evolutionists believe that there is a personal god (usually, a Christian God) that has played a key role in the emergence of humanity. However, the spiritual/supernatural dimension of reality is considered as somehow separate from the everyday natural world. Science studies the natural world and everyday mechanisms. But that is a separate world from the dimension in which God exists. Stephen J. Gould famously argued that religion and science deal with separate magistrates, and theistic evolutions would generally agree. Francis Collins is a good example of a theistic evolutionist, and most Americans would probably fall under this heading. TEs differ some on the extent to which they look for evidence of God via the scientific lens. The more they argue that one can prove God exists via science, the more they overlap with IDers. The more they argue for separation of the domains of science and the domains of faith, the more likely they are to defer to mainstream biology on the question of the validity of natural selection and see those debates as not relevant for their faith.
Agnosticism is the position of being open to the possibility of there being or not being a God, and having not reached a firm conclusion. Agnostics generally argue that while the question of whether or not there is a "God" (or something) is unclear, they are quite skeptical of any particular claims that any one makes about God. Is God a he or a she? Is there one god or many? How do you know it is a He and He had a son? And so on. As skeptics, agnostics generally turn to science for their knowledge of how the world works and generally are impressed with the scientific consensus regarding evolution. Agnostics, however, would be open to the possibility of discovering evidence for a designer...although, they are generally not at all impressed with the claims of IDers.
Exclusionary naturalists claim that through science we know there is no God. Their narrative is that prior to science, people developed a wide variety of (false) myths about human creation (of which the Bible is just one of them). Then, via science, we discovered ways of getting at the truth and the truth of our existence is now understood. The universe has evolved over 13.7 billion years, and life on planet earth is a function of natural selection operating on genetic combinations through time. We know this, say the exclusionary naturalists, and to say otherwise is irrational and immature. Richard Dawkins is a good example of an exclusionary naturalist.
Understanding the Theory of Evolution from the Vantage Point of Mainstream Biology
The philosopher Stephen Pepper argued that common sense and refined knowledge, although related, are two separate domains of knowing, with the latter being grounded in but then emerging out of and critiquing the former. It is essential that the general population understand that knowledge in biology is refined knowledge. Although some might consider it "elitist", from the vantage point of refined knowledge it simply nonsensical to have uneducated individuals dismissing hard won, scientific facts about evolution, any more than it would be reasonable to listen to a child who said she did not believe in the Periodic Table. As such, most scientists, although dismayed by the disbelief in evolution in the general public, essentially dismiss such criticisms as stemming from ignorance and wishful thinking.
It is essential to recognize that within mainstream biology, evolution, meaning descent from a common ancestor, is an accepted FACT. In other words, it is beyond any rational doubt that billions of years ago there were single celled organisms and over time these organisms have evolved into the organisms alive today. CHILDREN SHOULD BE TAUGHT WHY THERE IS SO MUCH CONSENSUS AMONG MAINSTREAM BIOLOGISTS ABOUT EVOLUTION. Darwin's theory of natural section, combined with modern genetics, currently provides the generally accepted causal explanatory framework for the facts of evolution, although the completeness of natural selection for explaining evolution is more debated.
What about Intelligent Design? Do many biologists see in nature scientific/objective evidence for believing in a supernatural designer? In a word, no. The vast majority of biologists, like Francis Collins mentioned above, experience wonder and awe at the complexity of life, but do not see concrete, scientific evidence of a Christian God. For those scientists who are religious, they generally agree that that belief requires a subjective experience of a relationship with God and a leap of faith. Indeed, it is useful to note that even ardent supporters of ID do not think ID has reached the status of legitimacy that would result in it being taught in high school classrooms.
The above elements are crucial to understand from the point of view of the "teach the controversy" perspective. The fact of the matter is that there is not much controversy within mainstream biology that natural selection operating on genetic combinations through time is a key, if not the key, to understanding biological complexity. Nor is there any hard evidence for a designer (mainstream biologists generally reject Behe's claims). It is worth noting that there currently are a number of different elements that are emerging that are causing biologists to question the completeness of the modern synthesis, with some arguing that major, foundational revisions are in order. Although fields like population genomics are raising important questions, many Darwin skeptics are quick to jump on these findings and announce that Darwin is dead. This is misguided and there are two key points to keep in mind about these developments. First, given how successful the modern evolutionary synthesis has been and how much evidence there is in support of it, if it is "overturned", it will likely occur much like Newton was overturned by Einstein, meaning that future research might reveal that it was an incomplete explanation, but not an incorrect explanation. This is a big difference. Second, the issues that some biological scientists are raising at the forefront of biological research carry essentially no implications for what has made Darwin's theory so politically complicated. That is, the complications do not challenge the basic outline of "molecules to man" evolution, nor do they point to the existence of an intelligent designer.
This last fact is strong evidence in support of the idea that the controversy is not really about the science of biology, but instead is about a clash of worldviews played out in the political arena.
The Politics of Evolution
Although often not emphasized by mainstream politicians, it nevertheless is the case that evolutionary theory challenges common sense notions about the Christian narrative. Interestingly, this is one point--and just about the only point--that both Christian fundamentalists and humanistic skeptics agree on! In a nutshell, it is hard to see how both the evolutionary narrative and the Biblical narrative of creation are both true, at least in a straightforward way. Theistic Evolutionists believe that they are both 'somehow' true, but this clearly requires some mental gymnastics to understand (try to explain concretely how we are the product of random variation and selection AND God is purposefully guiding evolution towards creating man in his image). There are many thoughtful individuals who have done a respectable job putting these narratives together, but it nevertheless requires complicated reflection to do so in a way that is at least somewhat coherent (see, for example, the book Finding Darwin's God).
To understand the political forces at work, we need to understand how the American demographic understands human origins. Gallup polls have been tracking this issue since 1982. Specifically, Gallup has surveyed Americans regarding their beliefs about human origins with the following: Which comes closest to your views: 1) God created humans as is within the last 10,000 years; 2) Humans developed over millions of years, guided by God; 3) Humans developed over millions of years, God had no part. Notice that this question parallels the various worldviews reviewed earlier, with the first question closely representing the Young Earth Creation View, the second the views of Theistic Evolutionists and supporters of Intelligent Design, and the third generally representing the Atheistic/Agnostic view.
The results have been remarkably consistent over time. Between 40% and 47% of Americans endorse the creationist view that God created human beings pretty much in their present form at one time within the last 10,000 years or so, whereas between 35% and 40% endorsed the claim that humans evolved over millions of years with God guiding the process, and 9% to 16% have endorsed the secular evolutionary perspective that humans evolved with no guidance from God. (There has been a slight trend in the last few years to see an increase in the purely naturalistic account, and may be a decrease in the creationist account). And, as you likely would guess, among Red States and Republicans, much larger percentages agree with the creationist account.
Understanding the above percentages is crucial to understanding the nature of the controversy. This is because although there are many mainstream scientists who are theistic evolutionists, the institution of science has generally coalesced around an agnostic (and in some ways a passively atheistic) worldview. That is, in general, science currently has, as Pierre-Simon Laplace famously put it to Napoleon, no need for the "God Hypothesis". Given this, it is not hard to see why Christian conservatives like Santorum, who believe that the Bible is revelation and believe in forces like Satan experience modern scientific knowledge as threatening. Moreover, given the levels of religiosity, it is not at all surprising to understand why the emergence of Intelligent Design as a concept was welcomed by so many in the American population at large. Indeed, it was precisely this conflict between American piety and the scientific worldview that resulted in Philip Johnson, the Godfather of the ID movement, to mastermind "the Wedge" strategy, which was explicitly designed to unite the ID movement with YEC against the prevailing supposedly atheistic, materialistic, and reductionistic view advocated by natural scientists.
Where Do We Go From Here?
Virtually everyone agrees that our political structure is getting more and more polarized. There are three broad areas of political opinion that drive differences. First, in the economic sphere individuals debate about the role of government in taxation, and the regulation of business and income inequality, with conservatives tending to emphasize smaller, less intrusive governments and liberals emphasizing equality and fairness. Second, there is the international and defense policy, with conservative hawks generally emphasizing American exceptionalism, American interventionism, and aggressive measures for security and liberal doves generally emphasizing sensitivity, diplomacy, and reduced military involvement. Finally, there are the social issues, with conservatives generally emphasizing traditional Christian values and liberals emphasizing diversity, freedom, and minority rights.
The evolution controversy is central to the third domain of political dispute and it is essential that individuals have a solid understanding of the landscape of prominent worldviews and their relationship to views on religion. Some the take home messages that everyone should be aware are as follows:
1. There is enormous consensus in mainstream biology that evolution (both micro and macro) is a fact and that natural selection has been a primary driving force (although biologists do disagree some about the extent to which the modern synthesis offers a complete conceptual framework for understanding biology, and biologists are constantly testing and scrutinizing the theory).
2. Although evolution is accepted as a fact in mainstream biology, there are many people (but only a small number of scientists and an EXTREMELY small number of biologists) who challenge this assertion and claim that evolution is a farce. Although many critiques have been offered, most biologists do not find them compelling. Critics of mainstream biology generally reply that this because evolution itself is more religion than science. (It is also important to keep in mind that there has been almost no scientific knowledge developed from alternative viewpoints, meaning that there is essentially no science supporting a young earth or how an intelligent designer designed life).
3. Science is generally agnostic on the question of God, and most scientist view science as having no need for the God Hypothesis--meaning that most scientist find natural explanations satisfying for the phenomena in their fields. In addition, most scientists are in fact religious, and thus generally are theistic evolutionists in some form or another.
4. The controversy surrounding evolution is largely a political phenomenon and is directly tied to the clash between a traditional Christian narrative and the view of life afforded by evolution. The two most polarized views, YEC and exclusionary naturalism, agree on this point, whereas theistic evolutionists believe both the JudeoChristian narrative and the evolutionary narrative are somehow true.
5. YEC is defined against many domains of science, and is a position driven by religious fundamentalism. How much it should be systematically criticized is a point of debate. On the one hand, our culture gives religious beliefs special status and people are, of course, free to believe what they want. On the other hand, many argue that it should be systematically separated from theistic evolutionists and supporters of ID, and critiqued because it embraces dogmatism, anti-intellectualism, and makes erroneous claims about both science and religion.
I hope this has provided you with a basic frame to understand why there has been such controversy, and who the major players are.