Deflating Dobzhansky’s Grand Assumption, or Why Microevolution Does Not Lead To Macroevolution


Theodosius Dobzhansky on Equating Microevolution and MacroevolutionRecently, someone commented on a post on the CreationLetter.com site, So Much Depends On Evolution?:

“Micro and macro as the same thing at either end of a timescale, you cant just believe in 1 or the other, only both, otherwise creationists should pick a different name for it.

These 2 words only come up when talking to creationists, never have i heard them in a lecture hall.

People that understand ”micro” but not ”macro” are either so differing in world view (YEC etc) or a bit dim, narrow minded and sheltered.”

So he had 3 basic objections:

  1. That macroevolution and microevolution are just evolution set to the tempo of different timescales
  2. That the macro-/microevolutionary distiction only comes up when talking to Creationists, not in lecture halls
  3. That people who accept microevolution but not macroevolution are either Young Earth Creationists [well, duh], dim, narrow-minded or sheltered.

Before I answer his objections, let me define a few terms for you. Macroevolution is the sort of vertical [phyletic] microbes-to-man change in which one kind of animal is said to change into another [viz. dinosaurs to birds]. Microevolution, a term used by Leavitt in 1909 describing developmental biology, was misappropriated and equated with Natural Selection and Speciation and then erroneously decreed as being Darwinian macroevolution on a small scale as early as 1927. That’s the rub really: evos claim that micro [small] changes eventually accumulate and bringh about macro [big] changes.

Biblical Creationists on the other hand affirm observable Natural Selection and Speciation, but we object that neither in geology [the fossil record] nor in extant biology do we actually observe vertical fish-to-philosopher macroevolution.

In 1937 Theodosius Dobzhansky, one of the architects of the Modern Evolutionary Synthesis [the sort of evolution that’s current taught in textbooks], wrote in Genetics and the Origin of Species:

“There is no way toward an understanding of the mechanism of macroevolutionary changes, which require time on a geological scale, other than through a full comprehension of the microevolutionary processes observable within the human lifetime. For this reason we are compelled at the present level of knowledge reluctantly to put a sign of equality between the mechanisms of micro– and macroevolution, and proceeding on this assumption, to push our investigations as far ahead as this working hypothesis will permit.” [emphasis mine]

I’m certainly aware that Gary Hurd testified that the micro/macro distinction was a Creationist fabrication, which is why we’ve named this fallacious argument Hurd’s Turd in his “honor.” Note that this takes care of the commenter’s 2nd objection. If he hasn’t heard the macro/micro distiction in his lecture halls, well, I could make a suggestion aboout the selective presentation of evidence. I believe the term is “sheltered.”

Back to the quote. Note that Dobzhansky had to make an assumption that small changes could account for big changes. Why? Because he couldn’t observe them. Because such changes allegedly took place over long periods of time that were, well, prohibitive to say the least. So he had to make an assumption.

But aren’t we just dodging the issue. Surely small changes do accumulate into big ones given enough time. It’s simply logic, right? Well, no, because what we actually OBSERVE is far different from the claims of evolutionists. We see animals change over time, but there are limits to that change.

For example, bacteria may mutate to resist a vaccine but it remains bacteria. A finch or woodpecker might change beak sizes in dry/wet seasons, but they remain finches and woodpeckers respectively. Furthermore, we note that the information [genetic potential] was already there encoded in the animals DNA. No new information was added. All change is horizontal not vertical as would be necessitated by macroevolution’s claims. The deck was simply shuffled. Furthermore, we note that if there is a change in the amount of genetic variability, there is a decidely downward trend. For example, one could theoretically breed a poodle from a wolf [eventually], but you could never breed a wolf from a poodle [the latter of which is afflicted with so many genetic disorders as to make my point further evident]. 

Gregor Mendel on the Limits of Genetic PlasticityYou see, Creationists OBSERVE and therefore affirm horizontal changes via natural selection and speciation. Like Mendel [the Father of Genetics] we observe that kinds of animals have great genetic variability but also fixed limits [There is a fixity to phenotypic plasticity that the evolutionist does not admit to], so that we observe that a dog is still a dog and recognizably so, be it a wolf, English bulldog or a weiner dog. Ironically, the late Stephen Jay Gould noted that:

The history of most fossil species includes two features particularly inconsistent with gradualism: 1. Stasis. Most species exhibit no directional change during their tenure on earth. They appear in the fossil record looking much the same as when they disappear; morphological change is usually limited and directionless. 2. Sudden appearance. In any local area, a species does not arise gradually by the steady transformation of its ancestors; it appears all at once and ‘fully formed. (Stephen J. Gould, “Evolution’s Erratic Pace,” Natural History, Vol. 86, No. 5, May 1977, p. 14)

Now let’s examine that quote a little more closely:

The history of most fossil species includes two features particularly inconsistent with gradualism [gradualism: ie., mainstream evolution as taught in our public school textbooks]: 1. Stasis. Most species exhibit no directional change during their tenure on earth. They appear in the fossil record looking much the same as when they disappear; morphological change is usually limited and directionless. [A dog is still a dog and recognizeably so, be it a wolf, English bulldog or a weiner dog.] 2. Sudden appearance. In any local area, a species does not arise gradually by the steady transformation of its ancestors [and keep in mind that a species arising “gradually by the steady transformation of its ancestors” is pretty much a textbook definition of the sort of evolution our textbooks teach. But instead of OBSERVING what’s taught in textbooks in the fossil record we see instead that]; it appears all at once and ‘fully formed.

Now does that sound more like vertical [phyletic] goo-to-you-by-way-of-the-zoo evolution or does it sound more like the concept of horizontal variation within created kinds via natural selection and speciation [the sort of thing we actually OBSERVE in extant biology]?

So to answer the commenter’s 1st and 3rd objections, we note that the macro-/microevolution distiction is decidely NOT one of mere timescale. Vertical goo-to-you macroevolution would require [not simply large amounts of time] increases of orders of genetic information and this is something we simply do not OBSERVE in proposed “microevolution,” aka observable natural selection and speciation which only result in horizontal changes at best and a downward trend in plasticity overall. At the risk of redundancy, I must stress that this is the exact opposite of the macroevolution claim and that Dobzhansky’s assumption has proven unjustified. It’s like saying we can make a billion dollars out of ten dollars by shuffling the pile around a bit. Worse! It’s like saying we can make a billion dollars out of ten by shuffling the pile and taking away a dollar at random intervals!

So to conclude:

  1. The Macro-/Microevolution distiction isn’t just a matter of timescale. The vertical [phyletic] microbes-to-man changes claims of macroevolution require increases of orders of new genetic information which are not evident in the proposed mechanisms of microevolution; instead natural selection and speciation are observed to simply shuffle existing information and a trending net loss of genetic plasticity. Microevolutionary changes are horizontal not vertical and thus cannot accumulate to account for macroevolutionary assumptions.
  2. The micro-/macroevolution distinction is not simply a Creationist fabrication. If the commenter hasn’t heard it mentioned from his lecture halls he would be well within his rights to demand whynot.
  3. People who do not accept macroevolution but do accept microevolution are not dim, but rather better informed; no more narrow-minded than the fellow who demands that microevolution is macroevolution in miniature; and rather less sheltered than the faithful evolutionist students who suffer from a selective presentation of evidence in their own lecture halls. And since evolutionists like Gould do not accept that microevolutionary processes are sufficient to account for macroevolutionary assumptions either – so that he was forced to come up with puctuated equilibra [punk eek; ie., the proposal that life goes along as we observe only to be interupted by magical leaps of macroevolution that leave no trace in the fossil record] as a supplemental mechanism to microevolution to accomplish the lofty claims of vertical fish-to-philosopher macroevolution – the commenter is simply offbase when he suggests one must be a Young Earth Creationist to doubt the accumulative nature of microevolution to macroevolution. It’s not just the Young Earth Creationists who doubt it; it’s anyone who’ll honestly examine the evidence rather than holding the faith and clinging to Dobzhansky’s proposed assumption of equivication.

Think about it,

Sirius Knott

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14 Comments Add yours

  1. First of all, good job rounding up related material and making your case. Perhaps it holds little relevance, but I would like to mention that Dobzhansky was a Christian and contributed to our understanding of the world, so I’m a fan. Your quote from him is accurate, but could use some context.

    The body of his work demonstrates that the macroevolutionary inference was developed through much more than simply observing microevolution. There’s nothing wrong with making an assumption and forming some hypotheses and even wild guesses to get you started – but science begins when you TEST those assumptions, and evolution has passed the test with flying colors in the opinion of most scientists. It’s this science Dohzansky rests his reputation on, not the assumption. The genome looks exactly as evolution would predict, and I can’t image Mendel holding his claim to genetic limitations if he had lived to see genomes of different organisms mapped out and compared. NOTE: I know his post-mortum position is hopelessly debatable, but I’m only pointing out that although his contributions were huge, he only had a small glimpse of modern genetics to look at so we can’t say he would make the same statement if he had today’s evidence.

    Macroevolution can and has been observed, and it’s in the process of happening right now in ring species like the Ensatina salamanders. Here you have sub-populations of these salamanders ranging from Oregon to Southern California which can reproduce with adjacent sub-populations but not subs too geographically distant because their microevolutionary differences have made reproduction impossible. All of these are still placed into one species, but if a few of the populations in the middle die off, you will have two isolated populations which cannot interbred and would therefore be two distinct species. A runaway exotic pet could multiply and kill off a few sub-populations or some large-scale land development and then the macroevolutionary change is complete. The two populations will always belong to the salamander family, but they will be new species, unable to interbred, and likely to develop differently as time goes by and environments change (and history strongly records evidence that environments always do.)

    Evolution would actually be disproved if a bacteria became something other than a bacteria. Things don’t hop branches, but they may split into two branches in the same clade, and this movement by all evolutionary understanding would only go in the wolf to poodle direction, not the reverse. Also, the claim that new information is never added ignores the frequent, documented cases of gene duplication and viral insertion which have added new information and functions (digesting nylon by duplication and subsequent mutations and the ability to form placentas in placental mammals and other such new functions has been linked to viral code insertion and even Answers in Genesis knows it.)

    As for past macroevolution (which can only be deduced by science and of course wouldn’t be eye-witnessed,) and to address some of your other points, take a look at llamas and camels. South American llamas and Middle Eastern camels would only appear to show up “sudden” and intact if you deny that they can be traced to extinct North American camelids. Enough fossil evidence of this ancestor and geological evidence for land-based migration at the right place and time exist for the right camelid group to split into these two species. Extant camels and llamas have such strong familiar similarities that even Answers in Genesis acknowledges they are related. Since they are two very distinct species, macroevolution apparently occurred and even AiG admits it, although they think this happened in hundreds of years rather than 25 million.

    1. Sorry. This comment got buried under a few others and I just noticed it.

      4 comments:

      1] Dobzhansky himself admitted it was an assumption, even if reluctantly made. Why are you apologizing for him? He had the honesty to admit it, whether you like the implications or not. If he had the integrity to make this admission, let it stand rather than making excuses for his embarrassing admission.

      2] Your assertion that macroevolution is being observed now betrays your lack of comprehension of the terms micro- and macroevolution. The time scale involved prevents us from observing macroevolution. All we are actually capable of observing is microevolution. Hence Dobzhansky’s assumption. At least he was honest enough to note a difference between the two and also note the impossibility of observing macroevolution. You might assume that the microevolution you are seeing now will eventually lead to macroevolution, but you’d still be making Dobzhansky’s assumption [and all of the examples you give [like ring species] are examples of observable horizontal changes within a kind of animal [yes, camels and llamas are considered to be in the same baramin]. The mutations you mention [irregardless of the significance you place on ERVs] are usually deleterious and only involve shuffling and loss of things already present, switching things on and off, etc.

      Wow. I need to make this bluntly clear, don’t I? Speciation is not macroevolution. We acknowledge speciation as variation within created kinds. Created kinds [baramins] are NOT anaologous to species. [It generally lines up with the family level] So again speciation is NOT macroevolution; it’s exactly the sort of microevolution Dobzhansky said we are able to observe [as opposed to unobservable microbes-to-man [phyletic] macroevolution.

      3. Stating that AiG acknowledges certain data without clarifying that they interpret the data differently is, well, just misleading. I do encourage anyone reading these comments to read the links to Answers in genesis provided and see how a Creationist might interpret the same evidence evolutionists interpret as evidence for their theory.

      4. The claim that “Evolution would actually be disproved if a bacteria became something other than a bacteria.” is patently ridiculous. That’s exactly what evolution claims. It claims that by gradual adaptation, one-celled organisms eventually became multi-celled simple organisms, which continued to gradually change until they became fish, then frogs, then reptiles, then mammals and eventually on to man. If modern-day bacteria became something else, it would be the long-sought-for proof of evolution, not disproof.

      1. modsynth says:

        re: 2. I was using the definition of macroevolution as scientists use it today: changes at or above the level of species. What most of us refer to as microevolution is a change in allele frequency below the species level. Speciation involves macroevolution by all modern definitions. Now that I see your personal definition, and found an even more drastic one on Conservapedia that defines it as a change in clade (how could any living thing become no longer related to an ancestor?) I understand that my examples of macroevolution don’t fall into these categories. I don’t feel that I deserve to be labelled ignorant for using the dictionary definitions (which includes speciation.)

        re: 3 I do not believe I was being “misleading” at all – I put links there for people to click on and investigate, and I pointed out AiG’s differing interpretation on the time scale. They acknowledge that new information can be added to the genome because that’s a plain, observable fact. Several things can add to the genome, and some mutations are agreed to be beneficial even by creationists. The claim that “No new information was added” remains false.

        re: 4 Evolution moves further down the taxonomic levels, not backtracking and making a turn down a different branch. If modern-day bacteria turned eukaryotic, modern evolutionary synthesis would have no way to explain it. To suggest something could somehow evolve up and then hop over is getting into Hovind territory where he pretends that evolution predicts a dog/cat intermediary or the infamous Croc-o-duck that Kirk Cameron talks about. Evolutionary theory does not predict and could not explain any such ridiculous thing.

        I also would like to clarify Gould in his own words since you brought him up and made it sound as if he did not see transitional forms at high levels: “Since we proposed punctuated equilibria to explain trends, it is infuriating to be quoted again and again by creationists — whether through design or stupidity, I do not know — as admitting that the fossil record includes no transitional forms. The punctuations occur at the level of species; directional trends (on the staircase model) are rife at the higher level of transitions within major groups.”

        Since the Bible doesn’t offer a clear definition of “kind,” I find baraminology to be too cloudy to test and not useful. Only YECs use the term, and each source seems to have their own definition of a “baramin.” If you can find a transition between two, it’s just called a third baramin, or all three are lumped into one big baramin. The goal post is constantly moving. In which baramin would you place tiktaalik? Archeopteryx?

        If everything under the baramin level is only microevolution, including camels and llamas from a common ancestor, where do you break from Linnaean classification and separate humans and apes? If humans are their own baramin, why do camels and llamas have to share one? Do you put blue whales and dolphins in one baramin? I really am curious, not trying to sound confrontational. Has someone set out to clearly define this concept and classify life accordingly?

      2. re: 2 – I have always found it duplicitous that modern-day evos define macroevolution as speciation when Dobzhansky specified that mac-evo was unobservable and he and the other architects of the modern synthesis had already observed speciation. At the very least, they moved the goalpost. Modern-day Creationists affirm the processes traditionally called micro-evo [natural selection and speciation] because they are observable; they also line up with the Biblical concept of a “created kind” or baramin, which generally we find to be at the Family level. This is not “my personal definition” as you put it. It is pretty much the standard position for the Biblical Creationist; hence, my charge of ignorance.

        re: 3 Neither Answers in Genesis [nor myself] deny that any information is added, but it’s simply not the type or amount of info required for mac-evo to work.

        re: 4 OK, you took me ultra-literally. Gotcha. You’re dodging the main issue. Would you prefer I labelled it vertical [phyletic] microbial eukaryote-to-man evolution? Vertical microbes-to-man evolution does predict that one kind of organism will eventually transform into an entirely different type of organism, something we don’t see in biology nor in the fossil record. Lacking this direct observational confirmation, you are left with Dobzhansky’s Grand Assumption.

        re: Gould. We’re perfectly aware that he still affirmed evolution. We take him as a hostile witness. You see, he came up with punk eek to explain away the absence of evidence for mac-evo, the innumerable trasnitional forms predicted by Darwin’s theory [rather than the handful of disputable candidates we see today]. It goes without saying that Gould too is borrowing Dobzhansky’s Grand Assumption but adding the escape mechanism of saltations. He’s also missing the point [and this is where we Creationists must simply accuse our opponents of gross and willful ignorance] ignoring the fact that Creationists affirm observable speciation but note that the plasticity of a kind of animal has observable limits [a dog is still a dog and recognizably so, be it a wolf, dingo, English bulldog or a weiner dog]. Gould conjures up saltations beyond the species level to explain the dearth of evidence of mac-evo in the fossil record. But he’s simply assuming that something akin to mac-evo happens in leaps.

        re: Baraminology. The Bible doesn’t offer a clear definition of kind any more than science offers a concise definition of species. I don’t think you’ve really tried to do more than affirm your own bias against baraminology. I’m not sure which baramin Archaeopteryx would go in, but since it’s recognized to be a perching bird, I can tell you it would be classified in a baramin class somehwere in Aves. TikTaalik? Give me the rest of the skeleton and I’ll make the attempt. Sometimes as scientists we simply have to shelve an immediate response for a more honest admission of insufficient data. TikTaalik presents a few problems. I mean, is it placental, marsupial, monotreme? We just don’t know much about it.

        Keep in mind that Linnaean classification is simply a useful framework and is no more infallible than the humans who created it. Blue whales and dophins are in recognizably different baramins. The false killer whale and dophins have been interbred [wholpins], so they are in the same baramin. You would break the human/ape barrier at human, obviously. Gorillas, chimpanzees, gibbons are all separate baramins. I’ve read at least one Creationist who puts austrolopithecines in their own baramin as well.

        The premiere group trying to further Baraminology is the BSG. Their website can be found at http://creationbiology.org

        -Rev Tony Breeden

  2. Anonymous says:

    Well done. I object strongly to the word “microevolution” because it makes implications of things which are not known to science. Science has demonstrated the limitation to variety within the kinds of life, and the absence of evidence has evos very angry in the current day.

  3. Deven Kale says:

    No, you’re just making up terms that make you sound like you know what you’re talking about, when really you’re just obfuscating the truth of evolution. Small changes, over generations, lead to big changes. That’s all that Evolution really claims. Vertical Phyletic change is just word salad: it sounds big and smart, but it doesn’t actually mean anything. Nothing in evolution claims that one animal changes into another. It claims that one population, over many generations, becomes something better adapted to it’s surroundings. And that, after millions of years, those changes from generation to generation can make them something barely recognizable as descendants of the original species.

    There is no equivocation in my statement, there is only understanding of the actual processes.

    1. Tony Breeden says:

      You repeat Hurd’s Turd. Gary Hurd also thought that the micro/macro evolution terms were a creationist fabrication, but it was Theodosius Dobzhansky [one of the architects of Neo-darwinism] who not only used the terms but suggested that they be conflated. Read the link I provided. Educate yourself. Don’t you realize you’ve been indoctrinated into believing an all-natural Just So Story? Saying we’re transitional simply begs the question.

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