…and this is a 
15 misconceptions about evolution
Category: Evolution
Posted on: February 20, 2008 11:44 AM, by PZ Myers
Take a look at this excellent list of evolution misconceptions. The entries are very brief, but mostly correct and very common: in particular, #12, "Natural selection involves organisms 'trying' to adapt" is one of the most common mistakes in creationist thinking — they completely miss one of the most important insights that Darwin had.
But I have to nitpick a little bit. #6, "The theory is flawed," gives the wrong answer — it basically tries to argue that the theory of evolution is not flawed. Of course it is! If it were perfect and complete we'd be done with it, and it wouldn't be a particularly active field of research. The "flaws" that creationists typically bring up aren't flaws in the theory at all, but flaws in the creationists' understanding of the science, but let's be careful to avoid giving the impression of perfection.
#15 is also a pet peeve: "Evolution is a theory about the origin of life" is presented as false. It is not. I know many people like to recite the mantra that "abiogenesis is not evolution," but it's a cop-out. Evolution is about a plurality of natural mechanisms that generate diversity. It includes molecular biases towards certain solutions and chance events that set up potential change as well as selection that refines existing variation. Abiogenesis research proposes similar principles that led to early chemical evolution. Tossing that work into a special-case ghetto that exempts you from explaining it is cheating, and ignores the fact that life is chemistry. That creationists don't understand that either is not a reason for us to avoid it.
#13, "Evolution means that life changed 'by chance'," also ducks the issue more than it should. As it says, natural selection is not random — but there's more to evolution than natural selection. It's a bit like ducking the question by redefining the terms. Much of our makeup is entirely by accident, and evolution is a story of filtered accidents. Creationists don't like that — one of their central assumptions is that everything is purposeful — but don't pander to their beliefs. Go for the gusto and ask them what their god was thinking when he loaded up your genome with the molecular equivalent of styrofoam packing peanuts, or when he 'accidentally' scrambled the sequence of our enzyme for synthesizing vitamin C.
Comments
Abiogenesis is different from evolution. "According to Hoyle" and others, the seeds of life could have come from off-planet, and then been subject to the evolutionary process. While evolution is the province of biologists who deal with replicating organisms, abiogenesis falls within chemistry. Sure there's a relationship--any biologist worth her salt figures that organisms came from simpler chemistry--but she doesn't have to worry about how it might have happened to study the process of evolution. 'Give me a replicator and I will fill the biosphere' is the creed of biology.
Posted by: Jim Wallis | February 20, 2008 11:59 AM
The misconception could be "Evolution is flawed, and THEREFORE, creation/design is true", i.e. arguing by elimination...
Posted by: PeteK | February 20, 2008 12:01 PM
The problem with Hoyle's panspermia is that while it would answer a specific problem, that of how life on earth originated, it does not answer the big question of how life originated.
In addition a number of the hypotheses for the origins of life involve self-replicators, that could not be said to be alive in the sense that is normally meant by that term, being subject to selective pressures.
Posted by: Matt Penfold | February 20, 2008 12:06 PM
I once met a guy who actually claimed that our inability to synthesize vitamin C was proof of the story of Adam and Eve, part of our punishment for original sin. Yeah, I laughed, too.
Posted by: Jayson | February 20, 2008 12:07 PM
Well now, "flawed" could mean "imperfect" or it could mean "undermined by mistakes so as to be invalid or unsound." In the first sense, the more usual one indeed, MET is flawed. In the second sense--if less common, the meaning that most anti-evolutionists prefer--evolution is not obviously flawed.
Since they're fighting anti-evolutionists, who typically misconstrue everything, I can understand why they say that evolution isn't flawed. Regardless of that, they'd have done better if they'd explained that most theories have issues and, in the lesser sense, flaws, and that these are rarely fatal to these theories.
Glen D
http://tinyurl.com/2kxyc7
Posted by: Glen Davidson | February 20, 2008 12:10 PM
Thank you! Darwin's proposal of evolution did NOT create the term. It utilizes an ancient concept to describe life. Abiogenesis is simply the start of the life process, as such, is an integral part of evolution.
Sheesh!
Posted by: Michael Bains | February 20, 2008 12:14 PM
Just as different disciplines have emerged as hybrids of those immediately "above" and "below" - e.g. physical chemistry, biochemistry, cognitive neuroscience, scientists have adopted "the E word", as Stephen Jay Gould put it.
But they could demarcate their corner of the evolution of the cosmos, while also allowing for significant overlap - e.g. Big Bang cosmic evolution merges into galactic evolution, merges into nucleosynthetic stellar evolution, merges into planetary evolution, merges into chemical evolution --> biological evolution --> cultural evolution, etc...i.e. one needs the the other(s), to proceed. The other "evolution's" are subject to many of the same misconceptions that biological evolution is suspectible to...
Posted by: PeteK | February 20, 2008 12:19 PM
That PZ continually lumps the two together is a pet peeve of mine. While it's true that evolution and abiogenesis are hardly completely separate, nonetheless there are processes presumed to occur in abiogenesis which are not part and parcel of evolution itself. Of course the degree to which we separate the two issues depends upon where we draw the line (in terra incognito, no less). However, at some point in abiogenesis we're dealing with the "random processes" (they're not completely random, of course, but are not subject to selection) which antievolutionists constantly accuse evolution as being.
Just because abiogenesis, at least at some point, may involve evolutionary processes does not mean that abiogenesis is evolution. Abiogenesis intersects with evolution, it does not fully coincide with evolution. The random processes involved in abiogenesis, which are not the same as the selectional processes involved in evolution, do set abiogenesis apart from evolution in an important way.
Simply lumping abiogenesis in with evolution distorts what we mean by evolution, the latter actually not being a matter of random events (even though these do exist in evolution). For abiogenesis is chemistry, at least at the earliest stages, with certain sorts of self-ordering processes occurring which do not include natural selection as such, while evolution is presumably defined as a process which includes natural selection.
The overlap between the two, as well as the lack of a clear line of distinction between the two, is no excuse for considering the two processes to be essentially the same thing. They are not, abiogenesis at the very least includes what precedes evolution.
In a Venn diagram, there would be an intersection between abiogenesis and evolution (depending on how we defined both processes, naturally), it would not be a union. Hence, there is no reason why the two should be considered to be the same thing.
Glen D
http://tinyurl.com/2kxyc7
Posted by: Glen Davidson | February 20, 2008 12:24 PM
It's really hard to explain things to people without falling on pathetic fallacies like "the system wants to go to equilibrium". I mean, in a deep sense, why does a chemical reaction appear to "want" to adjust to counteract perturbations from equilibrium? The problem is that in the case of evolution, somebody might reasonably assume that "it wants to" is not just a metaphor.
Posted by: Alex Whiteside | February 20, 2008 12:25 PM
I was sorry to see that one of the main misconceptions (in my opinion), which is that evolution is a kind of a chain or a ladder in which one speceis replace the one before it, is not only not refuted but actualy perpetuated in some of the pictures in this web page.
Homo sapiens did not evolved from Neanderthals, as the skeletons picture seems to hint.
Posted by: Tamar | February 20, 2008 12:25 PM
Still not with you on #15.
Whatever abiogenesis turns out to be, its pretty clear that the core mechanisms of natural selection that are so central to biological evolution: i.e. stable "enough" heredity with variation, are probably not going to play a major role. I mean, once you have some form of heredity, you pretty much have life right there and you're done talking about abiogenesis per se.
Creationists want to argue that the validity of abiogenetic description of life's origins and the validity of evolution via natural selection are linked. But they are not, not logically, and not in terms of their mechanisms. They may be linked historically, and as you say, you can probably draw a line through one to the other in terms of chemistry. But you can't in terms of the particular functional mechanisms, the likelihood and details of which are precisely what creationists are debating.
In addition, while one can call abiogenesis "evolution" in the same way that Hovind calls stellar formation "evolution," I think that's a pretty useless usage of the term. In fact, you could claim that all of abiogenesis and biological evolution is just a particular case of stellar evolution, but I don't think that would be particularly enlightening.
Posted by: Bad | February 20, 2008 12:26 PM
Incorrect. Evolution includes all the processes that are also active in abiogenesis, from chance to molecular biases to selection. Go ahead, name one basic property of evolutionary change not present in chemical evolution but there in biological evolution, or vice versa.
Posted by: PZ Myers | February 20, 2008 12:29 PM
I think this involves a fairly simple 'definition-error' (like the word 'theory' itself).
Flawed = imperfect, unfinished. Yes, the theory is flawed.
Flawed = incorrect, wrong. No, the theory is not flawed.
Not complicated, unless you're dishonest.
One further definition explains the problem.
Creationist = dishonest
(I see Glenn said it already as I was typing. What's a little repetition among friends... )
Posted by: pedlar | February 20, 2008 12:29 PM
Great points to keep in mind when discussing evolution with anybody, not just creationists. There are plenty of atheists out there that are just as vague on the specifics as any christian. Unfortunately, when I specifically bring up the "flaws" in our genome, I get the old fallback position from christian creationists - "Satan did it". Yep, everything from pilonidal cysts to our appendix to our inability to synthesize vitamin C is a result of Eve listening to a snake and picking some fruit.
Stupid is as stupid does. These people love them their stupid, and will go to any lengths to hang on to it.
Posted by: dorris | February 20, 2008 12:36 PM
Wait a second: You mean that five fingers on each hand is not the optimal number?
AGH!
Posted by: Bob | February 20, 2008 12:38 PM
Look, evolution means "change".. non-living material became living material....simple chemicals had to change into self-replicators, whether via panspermia, proteinoid microspheres, clay crystals, hypercycles, or whatever...
So, yes abiogenesis is an evolutionary process, but not a biological evolutionary process, since biology be definition is what abiogenesis RESULTS in!
Posted by: PeteK | February 20, 2008 12:39 PM
our inability to synthesize vitamin C was proof of the story of Adam and Eve
So eating the Forbidden Fruit led to our punishment - being forced to eat lots of fruit! Of course! How ironic!
Posted by: ajay | February 20, 2008 12:40 PM
Had you not cut off my parenthetical comment, which I restored in brackets, your comment would have been a non sequitur. Of course evolution includes chance, I said so.
I already did name one, which you blew off to demand from me again:
Depending on definition, abiogenesis might or might not include natural selection. The important point I was making is that at some stage in abiogenesis natural selection is not operative. Arguably, that is the most interesting part of abiogenesis as well.
And no, I don't care if abiogenesis is defined to include natural selection at some point (that would be merely a semantical argument). The crucial issue is that at earlier stages it does not include natural selection. That's why there's an intersection between evolution and abiogenesis in the Venn diagram, but no union between the two--because abiogenesis involves stages which are without the guidance of natural selection, which means that it doesn't involve biological evolution (only chemical evolution, which is quite different as normally understood).
Glen D
http://tinyurl.com/2kxyc7
Posted by: Glen Davidson | February 20, 2008 12:40 PM
Posted by: SeanH | February 20, 2008 12:46 PM
I'm not happy with lumping abiogenesis together with biological evolution either. Of course there are strong connections between the two, but there's certainly enough of a distinction to be able to draw a pretty bright line between them.
Would you want to throw in cosmological evolution as well? Yes, a naturalist account of the world is committed to dealing with everything eventually, but that doesn't mean that there aren't very important distinctions about the type of processes involved at different times and at different levels, and it makes sense to say that we can understand some processes (biological evolution) while we don't yet understand others (abiogenesis, planet formation, etc.).
How about having organisms as the environment for chemical transformations? A separation of the organism from the rest of the environment; having machinery in place for replication of molecular patterns, etc.
Posted by: Physicalist | February 20, 2008 12:47 PM
"Go ahead, name one basic property of evolutionary change not present in chemical evolution but there in biological evolution, or vice versa."
Natural selection may not be involved in abiogenesis. Heredity may not be involved in abiogenesis.
The point is the mechanisms and their respective plausibility. We know a lot about them in evolution. We don't in abiogenesis, and we have no reason to assume that they are the same, or that the same sorts of effects dominate. Saying that they all involve, well, "chemistry" is not a meaningful connection between the two.
And the difference in respective plausibility is clear and important. The plausibility of evolutionary change does not rest on the plausibility of any one abiogenetic possibility, and since we have no good idea which abiogenetic process is the right one, we have no idea how to describe it or rate it as more or less plausible given the environment it took place in.
Posted by: Bad | February 20, 2008 12:49 PM
"The theory is flawed," gives the wrong answer -- it basically tries to argue that the theory of evolution is not flawed.
Er - evolution is a fact, not a theory. Natural selection is one theory to explain evolution.
Posted by: Jit | February 20, 2008 12:52 PM
I know of no model of abiogenesis that does not include selection.
All abiogenesis models have a stochastic basis, but so does evolution.
All abiogenesis models also include intrinsic molecular predispositions, but the same is true of models of evolution that aren't hampered by the unfortunate bias of many people to equate evolution with natural selection.
Posted by: PZ Myers | February 20, 2008 12:58 PM
I should amend that, in order not to give anyone excuse to disagree over a mistaken phrase. This is what I meant:
Glen D
http://tinyurl.com/2kxyc7
Posted by: Glen Davidson | February 20, 2008 12:58 PM
According to my fundie "friends", not only does Satan's taint cover the whole earth, affecting every living thing, but the whole visible universe!!! In one discussion, I asked why such violent and destructive entities as supernovas and black holes exist if death and imperfection are caused by Satan's presence on earth. Not to be outdone, these nimble-minded debaters immediately claimed that what we see "out there" is influenced by our Satan-warped vision. Even the Hubble telescope and all the other technology floating around the solar system is not to be relied upon, since it was all constructed by evil, Devil-inspired scientists. Evil! All evil!!! In other words, don't believe your sinful eyes, ears, brain - absolutely nothing concocted by the mid of man makes the cut!
So it's the devil that made these people stupid...but you have to be stupid to take the Bible literally and believe in a sky fairy...so who made them stupid in the first place?
The sheer complexity of their logic boggles my mind!
Posted by: Dorris | February 20, 2008 1:00 PM
Evolution involves stages which are without the guidance of natural selection. Are you going to argue that evolution therefore doesn't involve biological evolution?
Posted by: PZ Myers | February 20, 2008 1:00 PM
And you know of no model of abiogenesis which includes natural selection throughout the entire process.
Really, quit playing word games. I've explained myself well, and you're ignoring the crucial distinctions that I and others have been discussing, and resorting to the ploy of bringing up the fact that abiogenesis is normally considered to have stages to which natural selection applies. That speaks not at all to the fact that abiogenesis models have stages in which natural selection does not apply.
Plus, the fact that people conflate evolution and natural selection doesn't change the fact that evolution is considered by almost all scientists to include natural selection--it is what causes "self-ordering" in biological systems.
So to conflate abiogenesis, which has non-selectional "phases", with evolution, which is normally considered to include (though is not wholly coincident with) natural selection, is taking the lack of a sharp distinction too far, by suggesting that there is no distinction at all.
Glen D
http://tinyurl.com/2kxyc7
Posted by: Glen Davidson | February 20, 2008 1:08 PM
Having gotten into a discussion on the subject of the origins of life vs the evolution of life, I suggest that the problem here is what is meant by the origin of life. If one defines the origin of life as the appearance of the first replicators (e.g. RNA), then there is complete orthogonality between origins and evolution. This is obvious because a mechanism like natural selection can't operate in the absence of a concept such as heredity.
Posted by: SLC | February 20, 2008 1:10 PM
PZ:
Life is PHYSICS, my friend.
The relevant question here is whether a good biological account *must* go all the way back to the point in the story where the characters are "mere" chemicals or "mere" sub-atomic particles. I see no reason that, qua the science of biology, it must do so. Remember that the solar fusion of elements is an important form of evolution too. But it's useful to distinguish this case from biological evolution.
Posted by: Physicalist | February 20, 2008 1:16 PM
"You mean that five fingers on each hand is not the optimal number?"
Heck no. Four is way easier to draw.
Posted by: Rey Fox | February 20, 2008 1:16 PM
I would like to know of these stages which are without the guidance of natural selection. I cannot think of any time period long enough to be called a "stage" which would be without natural selection operating.
But then again, geological evolution involves erosion and deposition. If there is a time period in which a portion of earth's surface is not undergoing either one, does that mean that geological evolution on planet earth doesn't entail erosion and deposition? Of course not, these are essential aspects of earth's geological evolution, regardless of the fact that these may stop between rains, for instance.
Likewise with natural selection. Even if you really know of stages in which natural selection is not operative, as much as I doubt that you do, that does not change the fact that natural selection is crucial to biological evolution. And not to the earliest stages of abiogenesis.
I am not going to engage in these word games all day, either.
Glen D
http://tinyurl.com/2kxyc7
Posted by: Glen Davidson | February 20, 2008 1:21 PM
Hurrah! PZ agrees with me!
I am always correcting the idea that evolution has nothing to do with the origin of life. Evolution kicks in as soon as you have imperfectly replicating doo-dahs. Now, it would be surprising if the first doo-dahs would be called "alive", but there is no doubt that the first cells would be. Somewhere between the two is a spectrum from nonlife to life. And the way that spectrum was travelled was almost certainly evolutionary in nature.
Posted by: Donalbain | February 20, 2008 1:24 PM
I know of no credible model of evolution which includes natural selection throughout the entire process.
I'm not playing word games. I'm saying that many people have this peculiarly fixed notion that the only kind of evolution that counts is the part that involves natural selection, and then jump further to the unwarranted assumption that all of evolution is about ns. You're using that logic to try and disqualify abiogenesis from being a subset of evolution. Discard that preconception, and you're left high and dry in your demand for special status.
What exactly is the crucial distinction you're trying to make? That one is chemical evolution and the other is biological evolution? There's no difference there, either, except in one word. And biology and chemistry (OK, chemistry is physics, too) aren't as discrete as people seem to think.
Posted by: PZ Myers | February 20, 2008 1:27 PM
By the way, apologies for my technical language.
Posted by: Donalbain | February 20, 2008 1:29 PM
I'm using "stage" in precisely the same sense you are. What stage of chemical evolution did not involve selection? How long did it last?
Posted by: PZ Myers | February 20, 2008 1:30 PM
I can't speak for Glen D., but my point is that one can investigate and understand processes at a higher level (and later in time) without investigating or understanding the underlying lower-level (and earlier) processes. There is a reasonable distinction that one can make between the evolution of biological entities, and the evolution of non-biological entities into biological entities.
You may be right to say that the same explanatory strategies we use in the case of biological evolution will also serve us in the case of accounting for abiogenesis. But (a) we cannot be nearly as confident of this as we are of facts of biological evolution simply because we don't yet have a good account of abiogenesis, and (b) even if it were to turn out that the actual explanation were very different from the sort of explanations involved in biology, this would, by itself, be irrelevant to our account of biological evolution.
Thus it seems to me to be a good idea to draw a clear distinction between the two (while also pointing out that the same sort of chemical processes are going to be involved in the two cases), and then to offer as a hypothesis the suggestion that the explanatory strategies that are successful in biology should also be successful in accounting for abiogenesis.
Posted by: Physicalist | February 20, 2008 1:43 PM
PZ,
I'm also very confused.
From the article on Talkorigins, "The Origins of Life", by Albrecht Moritz (Oct2006)
http://www.talkorigins.org/faqs/abioprob/originoflife.html
"Compared to science of evolution, the science of abiogenesis (origin of life) is still seriously underdeveloped in its explanatory power, despite the recent progress. As science writer Richard Robinson notes in his article: "Give biologists a cell, and they'll give you the world. But beyond assuming the first cell must have somehow come into existence, how do biologists explain its emergence from the prebiotic world four billion years ago?"
Indeed, it is one thing that we know all the chemical building materials of life, and that the functioning of life can be fully explained by their collaboration in an extremely complex system. Yet it is another thing entirely how, at the origin of life, they could have formed an initial organization by themselves step by step (via whatever intermediary processes and building blocks). At first glance, evolution from bacteria-like organisms (the last universal common ancestor) to humans may seem child's play in comparison: it started from an already tremendously complex, entirely self-sufficient, biochemical machinery and bit by bit simply made it even more complex."
Posted by: negentropyeater | February 20, 2008 1:43 PM
I've seen some of these "misconceptions about evolution" used by religious people in support of evolution:
11. Natural selection gives organisms what they 'need.'
12. Natural selection involves organisms 'trying' to adapt
14. Organisms are always getting better.
Welcome to Theistic Evolution 101, where arguments are made showing why and how God is working His Will through evolution and the Great Chain of Being. These folks may be on the same side politically ("Keep Creationism Out of the Schools"), but seems to me the scientific understanding of evolution still pretty much sucks.
Posted by: Sastra | February 20, 2008 1:45 PM
"Go ahead, name one basic property of evolutionary change not present in chemical evolution but there in biological evolution, or vice versa."
Self-replicating molecules. Evolution is the propagation of self-replicating molecules, abiogenesis is the formation of self-replicating molecules, whatever they were before evolving into DNA.
Posted by: Drekab | February 20, 2008 1:54 PM
Not buying this one at all. So there. You are wrong!!!
My definition of evolution is, The change in life through time.
Abiogenesis, life from nonlife.
These are very simple concepts in almost all 1 syllable words. Suitable for a creationist to understand. You have to realize that these people are a little bit "slow" (I'm being polite, actually they are very stupid) and type as slow as you can.
Besides which, we have mountains of data about the fact of evolution, 150 years worth.
For abiogenesis, very little real data about what happened circa 4 billion years ago, scraps of data, some hypothesis, some model systems. For various reasons, this has been a harder problem to study.
It makes sense scientifically and politically to separate the two subjects. The trend is to do so.
Posted by: raven | February 20, 2008 1:54 PM
Off the origins of life topic, but still on the "misconceptions" list (excellent overall, and concise enough for busy teachers to read and use), I think the #1 Misconception wording needs a critical fix:
We should never call "religious views" "theories", unless we simultaneously and repeatedly emphasize the difference between "vernacular theory" and "scientific theory". The word "ideas" in place of "theories" would work here.
Posted by: D. Denning | February 20, 2008 1:55 PM
Coincidentally, I just read a (very brief) interview of William Day by Lynn Margulis in which Day derides abiogenesis as "the origin of food", not the origin of life. Such "cake mix" approaches (combine the right chemicals, shake and bake) are bound to fail, in his view, because life is not a machine that you can put together from parts and then jump-start. Life is a process, a standing wave in the flow of solar energy, a continuous interchange of energy and matter with the environment. So the origin of life, he claims, is the point where that kind of self-sustaining pattern first began surfing the chemical and energy gradients and never stopped. Genes, replication, and evolution all came later.
I'm not sure I entirely buy that line of argument, but it's an interesting alternative perspective.
Posted by: Gregory Kusnick | February 20, 2008 1:59 PM
OK, first, what do you all mean when you say "natural selection"? I thought this meant environmental factors that impact whatever process is being examined (and I don't see how abiogenesis could be unaffected by environmental pressures).
Second, @ 30 REEEEYYYYYY!!!
http://scienceblogs.com/pharyngula/2008/02/beelzebufo_best_frog_name_ever.php#comment-755389
Posted by: True Bob | February 20, 2008 2:01 PM
I know of no credible model of evolution which can, even in principle, fail to include natural selection at any stage (unless one were to consider labs and "artificial selection" to be exceptions). Unless one is calling a comet strike a "stage," which, I think, rather strains the meaning of that word. How would natural selection be able to cease within a population, at least within a "natural population?"
I fail to see the connection, above or below, to discussions and definition of abiogenesis, the latter of which operates in earlier stages without reproduction, and thus without the ordering force of natural selection.
I neither said that evolution was all about NS, nor did I use the notion that "evolution is all about NS" as the reason why abiogenesis isn't a part of evolution. I said that evolution includes NS, that it is crucial, and that stages or phases of abiogenesis do not include NS.
What are we supposed to do, give up the peculiarities of biological evolution when defining what biological evolution is?
As an analogy, let's suppose that Esperanto becomes a living breathing language. While Esperanto's origin would in that case never be separate from its later evolution, clearly Esperanto was designed, and language evolution does not primarily occur by design (mostly it occurs by a selection of choices and unconscious processes, nothing we'd normally call "design").
Or perhaps closer to the point, Hebrew, a dead language, was revived in the state of Israel and remodeled to be able to discuss much that didn't occur in Bible times. The process of raising Hebrew from the dead, while not separate from later evolution of Hebrew, is certainly something that we can distinguish from it's stage of resurrection from the dead.
There are lumpers and there are splitters. In the big picture, we hope eventually to lump everything together, to see the seamless stages of cosmological, planetary, geological, chemical, and biological evolution. However, we come up with good reasons to split up various matters, and evolution and abiogenesis readily lend themselves to such splitting, which is done more for our convenience than because of any inherent differences (after all, natural selection is reducible as well).
No, you're far more the realist than I am. I'm more the continentalist, understanding issues like disciplines and species to be constructs than anything having "special status." That does not mean that I think everything is "really the same" at all, though, rather I can see the value and meaningful conceptual differences that split up the origins of modern Hebrew and the origns of life from their subsequent evolutions, based upon inherent processes involved in each respective case.
Sorry, you of all people should, and indeed do, know the differences between biological evolution and chemical evolution. That the former can be reduced to the latter is of no consequence to my understanding of the worth of the constructions used to differentiate between the two.
And sociology ultimately reduces to physics as well. What am I to make of that? Am I to tell everybody that their distinctions are unsound, just because one thing reduces to another? No, there are "higher order" designations that we retain because they are very useful to our various ways of conceiving the world. Biological evolution may reduce to quantum physics, in fact, but I will not fault biologists for existing just because of the reducibility of the observed classical "world."
Glen D
http://tinyurl.com/2kxyc7
Posted by: Glen Davidson | February 20, 2008 2:08 PM
It makes sense scientifically and politically to separate the two subjects. The trend is to do so.
Quoth PZ: It's a cop-out.
And I tend to agree --politically, or, closer to my heart, rhetorically. In a sense, it's not really even a scientific question. Is general relativity physics or cosmology? Makes no difference.
The issue for me is that the knee-jerk "Abiogenesis is NOT Evolution" is rhetorically soft and just sounds evasive. As if biologists don't envision extending the scope of the theory beyond the first cellular life. Ask yourself this: if we DID have a consensus model of abiogenesis, and it involved replicators 'all the way down,' would evolutionary theorists disown it? Of course not. It would be touted as an extension of evolution's scope and explanatory power.
Posted by: CJO | February 20, 2008 2:11 PM
D. Denning #41 wrote:
Although I take your point (different meanings of the word 'theory' are being equivocated on and that can lead to misunderstanding), I want to point out that atheistic arguments against the existence of God will indeed seriously consider religious views to be theories or hypotheses which can be supported or falsified by evidence. Scientific atheists such as Richard Dawkins, Taner Edis, Vic Stenger, and PZ Myers take this approach.
"God" is a failed or unnecessary hypothesis, inconsistent with our discoveries and cluttering up our understanding of the universe.
If you want to get to this point, then that's one good reason to call "religious views" "theories." If you want to protect faith in God from being scientifically shredded (for either personal or political reasons), then yes, you'll argue against considering religious beliefs about God to be anything at all like theories.
Posted by: Sastra | February 20, 2008 2:16 PM
To me, the worst misconception is the one that says that humans are the peak of evolution, that it was somehow aimed at perfect US, and that we're the best and greatest it could ever hope to achieve. Since we were the goal, since we're better than everything else, the rest of the ecosystem can all be carelessly sacrificed for our continued well-being.
Posted by: Hank Fox | February 20, 2008 2:22 PM
I disagree with PZ regarding abiogenesis. The key distinguishing characteristic of abiogenesis is the study of how non-replicators become replicators. You cannot have evolution without replicators, be they chemical or biological. Abiogenesis is the study of what the initial replicators were and how they came to be.
Posted by: Shygetz | February 20, 2008 2:22 PM
Um, really, I don't know how you're using "stage," for I know of no stage of biological evolution in which natural selection isn't operative. Maybe if you really went in with a conceptual microscope and looked at the peacock strutting before the peahen, you'd say that natural selection isn't operating (except that sexual selection is believed to involve the fitness of the, in this case, male bird, so whether you're really rid of natural selection there is in question, but arguable). Yet is that a "stage"? I would not think so. The whole population is what evolves (as we normally understand it), and it is difficult to leave out sexual selection's incorporation of aspects of natural selection at the stage of reproduction.
Chemical evolution did not involve selection at the stage of the production of the precursors of the biochemicals. The Urey-Miller stage of abiogenesis, so to speak. Indeed, that is the stage that we understand the best, even though many questions remain even in that area.
Polymerization of larger molecules also does not initially involve natural selection, although it is possible that very soon thereafter natural selection begins to factor into the equation. However, both production of the precursors and polymerization are important, for they are the grist which later stages of abiogenesis grind finely. Was RNA able to form early on from the chemical soup, or did some earlier stage lead up to the RNA world which appears to have left vestiges in today's life?
Getting to the stage where natural selection can occur remains a substantial unresolved issue within abiogenesis, for once natural selection takes hold things do not seem so difficult any more (at least not to me). Problems of the stability of RNA remain, so that people are working on variations of RNA which appear to be more stable.
As far as I know, it is yet resolved whether or not replicators are going to be called "life," or if replicators might still not count as life (viruses have often not been called life, due to their lack of metabolism when not infecting cells. But the recent tendency is to see these evolving replicators as life--few, if any, deny that viruses are subject to biological evolution). I have seen some call any replicators life, while others demur.
Anyway, at some point the issue of what "life" is does become murky, no question. As I understand it, though, abiogenesis is generally split off from evolution due to the fact that it involves life coming from non-life, which implies that biological evolution isn't occurring at some stage of the process at least, since imperfect replicators will be subject to natural selection.
Glen D
http://tinyurl.com/2kxyc7
Posted by: Glen Davidson | February 20, 2008 2:28 PM
I didn't know the guinea pigs were so evil...
Of these, only the last three should be called evolution because only they involve (pardon the pun) replication and inheritance, and the last one is so lamarckistic that calling it "evolution" is bound to lead to misconceptions, too.
Languages evolve, though.
Use the gravity metaphor then: once it's in equilibrium, it requires an effort to go anywhere else, so when that effort -- energy -- is unavailable, it doesn't go anywhere.
No, "change" means "change". "Evolution" means "descent with modification". There's replication, inheritance and mutation hidden in that definition.
Posted by: David Marjanović, OM | February 20, 2008 2:28 PM
"You cannot have evolution without replicators, be they chemical or biological."
Toothbrushes don't evolve?
Mountain ranges don't evolve?
Indeed solar systems don't evolve?
Evolution does not require replicators...only processes, ultimately guided by thermodynamics.
Posted by: Alex | February 20, 2008 2:29 PM
Dunno. But I consider "evolution" anything after the first self-replicating critter, and "abiogenesis" anything before it. Obviously, replicating things can do one thing that non- replicating things can't - spread their traits . And that is quite a huge difference... I would say.
Posted by: T_U_T | February 20, 2008 2:32 PM
That there is something qualitatively different between what we know as the theory of evolution and abiogenesis comes down, perhaps, to a matter of genealogy. We can trace back the ancestry of everything surviving on earth only so far, to a relatively limited set of LUCA (last universal common ancestor) organisms.
Abiogenesis steps beyond that realm. We have no outgroups with which to do genealogical analysis, so it ends up in the could realm instead of the did realm. While inspired by current life and extant Precambrian geology, unless there ends up being some strong chemical or geological implications from one of the abiogenetic hypotheses, what we may end up with are merely ways life can form. Such theoreticals may end up informing astrobiology.
It may not even tell us that life started here. Hoyle's vision of panspermia was somewhat reality-challenged, but more realistic scenarios where even semi-burnt husks of extremophiles gave life here a boost are still possible, though of utterly unknown probability.
I suppose what we're really trying to point out here is that evolution works even when totally devoid of a proven abiogenetic hypothesis. That enters into the evolution-creation melee because "you can't explain the origin of life" is a constant, repeating theme, and the implication is that if you include abiogenesis in evolution, then you're at the very least teaching children something far from proven if you teach them evolution. This leads to either special pleas for things that are "just as unproven as abiogenesis" (intelligent design, pick your poison) or just to further lambast it as a materialist fairy tale.
At the very least, from the point of view of education, since we are teaching children the scientific consensus, a separation between the very confident parts of evolutionary theory and the very speculative is required, even if the speculative gets a pedagogical mention (so long as it is presented as being speculative).
As far as research goes, then sure, blur the walls, since speculation and research in all of its mixed ratios goes together very well.
Posted by: Ritchie Annand | February 20, 2008 2:35 PM
Take a look at this excellent list of evolution misconceptions. The entries are very brief, but mostly correct and very common:
Same s**t, different day....
You guys crack me up...ROFLMAO!! You just seem to make this stuff up as you go along.
And you have the balls to call it SCIENCE?
http://youtube.com/watch?v=c3coSfks4rQ
Posted by: abu el banat | February 20, 2008 2:35 PM
So Glen /PZ,
Wadda we say to the IDiots when they start carping about evolution and how life began. I was telling them that evolution was about how life evolves and abiogenisis was the study of how life began.
Posted by: firemancarl | February 20, 2008 2:39 PM
David Marjanović, I usually enjoy your comments, and I rarely comment myself, so I hate to do so just to correct you, but, evolution does indeed mean "change." The word's been around a lot longer than Darwin, and is still used in other senses fairly commonly - maybe not as much as "descent with modification," but enough that you can't insist that that's the only common definition for it.
Posted by: Fatboy | February 20, 2008 2:41 PM
No, no, and no, respectively.
It certainly seems that way to you -- because you don't know what you're talking about.
Posted by: David Marjanović, OM | February 20, 2008 2:44 PM
"Evolution" means "descent with modification".
No. Not really. This is spinning the argument. It can mean that, but only in a narrow view of the term.
http://www.merriam-webster.com/dictionary/evolution
Posted by: Alex | February 20, 2008 2:44 PM
@ #51:
They certainly do not evolve by consisting of imperfect replicators (where these imperfections interacting with the environment drive a transformation of the group).Language is messy. We need to stipulate how we are using a term such as "evolution." We have a pretty clear account of what's involved in biological evolution. There are important similarities and important differeneces with other types of evolution, including abiogenesis. I suggest that the best way of avoiding confusion is to make distinctions by using different terms.
Posted by: Physicalist | February 20, 2008 2:45 PM
This is basic stuff here David Marjanović. It is pointless to argue the mundane fact of the definition of evolution and all it encompasses. I don't respect your authoritative dismissals, and I don't think anyone else here does either.
http://www.lpi.usra.edu/education/timeline/
Posted by: Alex | February 20, 2008 2:50 PM
Never, never, never cite a general dictionary on the meaning of a technical term.
Yes, the word "evolution" has been around for longer than Darwin, Lamarck or Buffon. All the way to Darwin's time it meant what is today called "development" in English -- ontogeny, that is. (That's because it literally means "unwrapping", which is what ontogeny was thought to be: the unpacking of the homunculus in the sperm.) That certainly has changed. But it's still a technical term. We biologists own it -- we get to decide how it should be used, not Merriam-Webster. I didn't say "the only common definition", I implied "the only correct definition".
Sorry to go all prescriptivist on you, but I really do think that technical terms are owned by those that work in the discipline in question.
Posted by: David Marjanović, OM | February 20, 2008 2:50 PM
Regarding the evolution/abiogenesis debate, I agree with the people saying that there should be a fuzzy line separating the two. After all, the entire history of the universe is a series of ongoing interrelated processes, so where we distinguish some theories is bound to be somewhat arbitrary, and the evolution/abiogenesis boundary seems as good as any.
On the other hand, I never play it up in debates with creationists, because it's pretty much a moot point. Most people who accept evolution also accept that there was some kind of abiogenesis (even accounting for panspermia, life had to start somewhere). Arguing the semantics of it doesn't change the actual history of events that occured on our planet.
Posted by: Fatboy | February 20, 2008 2:51 PM
It is narrow to assume that evolution does not occur outside of organic/biological spheres. That's not just what I say, that's the state of our understanding today.
Posted by: Alex | February 20, 2008 2:52 PM
"Never, never, never cite a general dictionary on the meaning of a technical term."
What?!
"We biologists own it"
Again - What?!
Here's my prescription to you. Try decaf.
Posted by: Alex | February 20, 2008 2:57 PM
Indeed. Languages evolve, too. Perhaps even universes do. And evolution can be simulated in computers.
That's not a matter of understanding, it's a matter of definition. What mountain ranges and solar systems do can be compared to development, but not to evolution. Individuals don't evolve, populations do, and when there's no population, there's no evolution.
Posted by: David Marjanović, OM | February 20, 2008 2:57 PM
PZ wrote:
How long will it be before the quote-miners get hold of this one, do ya reckon?
Posted by: RascoHeldall | February 20, 2008 2:57 PM
@Raven- force the creos to think! The division of 'life from nonlife' is a blurred area. If we talk 'replicators' , then the lattice of montmorellinite (smectite group) clay qualifies (remember the 'false positives' from Viking? Even the lattice of ice provides a staging area for groups of amino acids to come together. If replicating RNA is the definition, then precursor chemicals and model systems require research and our definitions possibly modified. I am disagreeing only to the point of getting across to creos that evolutionary biology, anymore than physics is complex and not a 'debating society' [other terms available when I am on my home computer] for underschooled (and often morally malnourished) flacks.
Posted by: mothra | February 20, 2008 3:00 PM