Darwin’s “theory of evolution” isn’t evolution; it’s natural selection

I can always tell when an opponent of Darwin’s “theory of evolution” has never read Darwin, because they try to claim that Darwin’s “theory of evolution” means that “evolution is a theory.”

Unfortunately for them, the phrase “Darwin’s theory of evolution” does not mean evolution was Darwin’s theory.  Scientists recognized evolution long before Darwin came along, and they understood it not as a theory, but as a fact that they observed both in nature and in the laboratory.  They could see changes over time to species in nature, and they could manifest evolutionary changes themselves in their labs using species that reproduced very rapidly, such as fruit flies.  To a scientist, “evolution” is merely another word for “mutation,” and there simply is no question that mutation is a fact — whether we are talking about a human who is born with a birth defect (or a unique talent), or a bird flu virus that mutates to be able to spread by person-to-person contact.  Evolution simply means “mutation” or “change over time.”  Such “evolutions”…such “mutations”…such “changes over time”…are proven facts.

The critical quesion is what causes such evolutionary changes to occur?  The reason Darwin drew attacks from Christians for his “theory of evolution” was not because he proposed the idea of evolution; the reason he drew attacks was because he suggested that nature itself, not God, was the driving force behind evolution.  Thus, just as Newton’s “theory of gravity” was not gravity itself, but rather the rule by which gravity operates; Darwin’s “theory of evolution” was not evolution itself, but rather the rule by which he believed evolution operates — namely, natural selection.  Just as we do not say, “Newton had a ‘theory of gravity,’ therefore gravity is a theory,” we should also not say, “Darwin had a ‘theory of evolution,’ therefore evolution is a theory.”

So, why was natural selection (Darwin’s “theory of evolution”) so earth shattering in the 19th century, and why is it still so controversial today?  Mainly because the reasoning he set forth in his book, “Origin of Species,” was VERY convincing.  It was so convincing that the Christian church was unable to effectively contradict it.  Indeed, it was so convincing that it is what gave rise to Christian Fundamentalism.  Fundamentalism was specifically created in the 19th century by people who refused to believe Darwin’s theory of natural selection, but they had no equally convincing argument with which to oppose it, so they created their own version of Christianity — Fundamentalism — that declared the Bible to be literally true.  It was the only argument they could think of to contradict Darwin, and it consisted essentially of saying that any scientific data which contradicts their own pre-conceived interpretation of the Bible must be wrong.

In sum, Darwin’s great contribution to science was not in being the first person to suggest that evolution happened; his great contribution was in being the first to convincingly suggest a convincing mechanism for why evolution happened as it had been seen to happen.  He was the first to propose a theory that seemed to fit the available data:  the theory of natural selection.  That is Darwin’s “theory of evolution.”

So, what is “natural selection?”  A detailed explanation can be found here.

Share

grumpypilgrim

Grumpypilgrim is a writer and management consultant living in Madison, WI. He has several scientific degrees, including a recent master’s degree from MIT. He has also held several professional career positions, none of which has been in a field in which he ever took a university course. Grumps is an avid cyclist and, for many years now, has traveled more annual miles by bicycle than by car…and he wishes more people (for the health of both themselves and our planet) would do the same. Grumps is an enthusiastic advocate of life-long learning, healthy living and political awareness. He is single, and provides a loving home for abused and abandoned bicycles. Grumpy’s email: grumpypilgrim(AT)@gmail(DOT).com [Erich’s note: Grumpy asked that his email be encrypted this way to deter spam. If you want to write to him, drop out the parentheticals in the above address].

This Post Has 13 Comments

  1. Avatar of Erich Vieth
    Erich Vieth

    You’re right to look at Darwin’s scientific theory in two distinct parts, the first of which consists of the random changes in organisms. Beaks get a little longer or hair changes color. These changes happen all the time (even within a particular family within a short time-span). No one disputes that.

    What is amazing is that these random changes somehow aggregate in a “direction.” A design emerges: a solution to a biological problem. How dare the scientists say that randomness can do THAT?

    Whenever we see a successful design, though, we don’t see the millions or billions of unsuccessful attempts randomly thrown together, very few of which produced any offspring and most of which died long before reaching adulthood. If we use our imagination, we’d see a biological landscape strewn with these failures. Incredible numbers of horribly disfigured and dysfunctional organisms. It would make one think that nature is an abject failure, constantly making unfit living things, then discarding them. As Daniel Dennett writes in Breaking the Spell, “Evolution is all about processes that almost never happen.” But they do happen, and they do so incrementally, not easily perceptibly in a single lifetime.

    In other words, what evolution lacks in brains (it has none, actually) it makes up for with blind stamina.

    The thing that locks in these changes is what Darwin termed “natural selection” (to contrast it to the “artificial selection” used uncontroversially and to great effect by animal breeders). Natural selection is the weed of “breed and weed.” It is the ratcheting of slight advantages—Francis Crick (1968) termed these “frozen accidents.” This selection of randomly generated mutations is not random. The changes that are passed on must pass a very difficult test: they must make it more likely that an organism will survive and produce offspring.

    Still, the fundamentalists never paid much attention to these theories until scientists started applying them to human animals. That’s when the fundies got that sick feeling, looked in the mirror and ran for their Bibles screaming “I’m an ANIMALLLLLLLLLLLLLLLLLLL!!!!!!!!! AAARRRRGGGGHHHHHHHHH!!!!!!!!! They assumed that Darwin’s theory instantly changed who they were, even though this was untrue. They remained who they were: fantastically designed human beings, though unnecessarly scared of their evolutionary past (this is before they obsessed about terrorists and immigrants). But because they couldn’t easily shake off the word “animal” any more, they worried that someone was going to put them in a zoo or feed them crackers through the bars of a giant birdcage. None of that happened, of course, but Darwin’s theory, the one that inspires people like you and me, nevertheless terrifies the fundamentalists.

    Mostly, they are shocked to think that simple things could evolve into complex things without a God drawing up the blueprints on His CAD program in the sky. The possibility that God might be superfluous made their heads hurt and they decided that they’d rather not think about it any more. Most fundamentalists have chosen to shut off their senses of wonder in order to instead enjoy a commonly offered benefit of religion, a thing Dennett calls “premature curiosity satisfaction.”

  2. Avatar of Niklaus Pfirsig
    Niklaus Pfirsig

    I think what really angers the creationists is that the idea of evolution through natural selection implies that man is not the ultimate life form since evolution is a continual process.

    Another major misconception is equating the complexity of organic chemistry as being counter-intuitive the the laws of entropy. They misunderstand the entropy is concerned with energy, not complexity, and in chemistry, it is the slower, less energetic chemical chemical reactions that can form the more complex compounds.

    for example, a mixture of powdered aluminum and powdered rust will easily ignite and the aluminum with rip away the oxygen from the rust while releasing tremendous heat in the process. the result is a blob of molten iron with bits of aluminum oxide (aka quartz) floating on it. quartz is extremely stable. ON the other hand, most organic reaction release tiny amounts of heat, and the resulting compounds are quite easily broken down, and rearanged by chemical means. 

    So in fact, the complexity of life, which is based on organic (carbon) chemistry, is exactly in line with the laws of entropy. 

  3. Avatar of projektleiterin
    projektleiterin

    I had a microbiology professor who wrote a book about evolution – from a critical point of view. He is not only a "simple" associate or assistant professor, but the head of the department and I actually liked his classes. I haven't read this book, but from what I have been able to gather from the reviews it seems that he and his co-author propose a creationism theory plus a downstream (?) evolution. So, they do not completely deny evolution, but they set out to show that weaknesses in the scientific works do exist and claim the possibility of a different explanation for the origin of the universe.

    Somehow I think I need to get my schoolbooks out and refresh my knowledge about evolution, because I bet a discussion with him would be really tough. 😀

  4. Avatar of grumpypilgrim
    grumpypilgrim

    Projektleiterin, please remember that evolution does not and cannot (yet) explain the initial creation of life on our planet; it merely seeks to explain how life, once created, might have evolved through natural processes into the variety of forms we see today. Accordingly, arguing in favor of supernatural creation of life (i.e., at the beginning) is relatively unrelated to the subject of evolution. Until someone discovers a natural process that creates life from non-life, the creationism "theory" will remain as valid (i.e., not disprovable) as any other.

  5. Avatar of grumpypilgrim
    grumpypilgrim

    "…the resulting compounds are quite easily broken down, and rearanged by chemical means."

    Sounds to me like this would create a chemical environment that would foster the creation of many new compounds…perhaps compounds that can metabolize, grow, reproduce and adapt to their environment; i.e., life.

  6. Avatar of projektleiterin
    projektleiterin

    Grumpy, the creationists poke holes in your evolution theory to support their idea of a divine creation. I'm also not sure why you say that these two are not related, evolution explains how the different life forms evolved, from simple to complex. If you can't trace life back to something simple you will have problems explaining the origin of life with the current scientific theories or am I mistaken?

    By the way, my post had more anecdotal character, I didn't intend to sidetrack and start a discussion about evolution and creationism.

  7. Avatar of Edgar Montrose
    Edgar Montrose

    Just a bit of nit-picking: quartz is silicon dioxide. Aluminum oxide is corundum. Sorry; it's the engineer in me.

  8. Avatar of grumpypilgrim
    grumpypilgrim

    projektleiterin, creation and evolution are two different things. As I said, evolution cannot (yet) scientifically explain how life initially began — how the very first living organism(s?) on our planet came into existence. It can explain how life might have evolved from that early beginning into its present diversity of forms, but this still leaves a door open for people who want to speculate about divine creation (or other types of creation) regarding the very first life on earth.

    Also, evolution is not always about life evolving from simple to complex; it is about life evolving from forms that are less-adapted to forms that are better-adapted to their environment. This doesn't always involve more complexity. Forms that are already well-adapted to their environment (sharks, turtles, frogs, etc.) can remain apparently unchanged for many millions of years. Likewise, excessively complex forms of life can evolve to less complex forms, as when cave-dwelling species lose their eyesight. The notion of complexity also opens the door for entropy arguments such as the one Niklaus discusses. True, evolution can explain how complex (i.e., more-specialized) forms might develop from simpler (less-specialized) forms, but its power to explain extends to other phenomena as well.

  9. Avatar of projektleiterin
    projektleiterin

    I'm going to hide now… :p Nah, my brain just feels so fried at the moment, I need some sleep before I jump into another discussion. 😀

  10. Avatar of Ben
    Ben

    I see a conflict between the Story of Creation and the Theory of Evolution. Some folks say they don't, and I must trust that they are being honest with themselves. In my opinion, if Creation happened as told, then evolution is not needed and is contradicted even, because Adam and Eve are fully formed upon Creation. In order for Evolution to even make sense, Adam and Eve would have to be just the names given to a mat of blue-green algae, and the "snake" would actually have been a trilobite. This leads to all sorts of speculation (by loonies) about whether God actually created the world in 6 days, or if "6 days" could be analagous to "6 thousand (billion?) years". Some scientists are able to entertain/accept both Creation and Evolution, as well as most moderate Christians I meet. I will mercifully stop there, before Grumpy has an aneurysm.

  11. Avatar of grumpypilgrim
    grumpypilgrim

    Ben, please observe that I was talking about "creation" (small "c") not the Bible's "Story of Creation." I agree with you in seeing a conflict between the Story of Creation and the Theory of Evolution, but there is not (yet) a provable conflict between the Theory of Evolution and the notion of divine (or at least extraterrestrial) creation. Not creation as in the Story of Creation, but creation as in some extraterrestrial seeding our lifeless planet with living cells. I still don't believe it happened that way, but science cannot yet prove that it didn't happen that way; thus, there is not necessarily a conflict between the Theory of Evolution and the many (as yet unproven) ways in which the very first life form on our planet might have originated.

    As regards the people who can "accept both Creation and Evolution," the people I've met who do so are all deists who reject the Story of Creation as being fictional. They believe the Bible cannot be accepted as literally true and, instead, postulate the existence of a supernatural power (called "God" in the Bible) who sparked the first life on our planet and then sat back (spiritually speaking) and let evolution run its course.

  12. Avatar of Ben
    Ben

    Actually, I am not completely opposed to the idea of some kind of spores/viruses travelling through space inside comets. Especially since we are now learning how robust life is, even thriving in extreme environments (which WE consider extreme).

    http://www.space.com/searchforlife/aliens_all_001

  13. Avatar of projektleiterin
    projektleiterin

    "who sparked the first life on our planet and then sat back (spiritually speaking) and let evolution run its course."

    That's Star Treck theory. 😀

Leave a Reply