A very nice post by Barry at UD struck me as worth reposting here (as I can’t post there), inspired by Neil Rickert:
Phinehas asks Neil Rickert a fascinating question about the supposed direction of evolution. Neil says he will address it in a separate thread, and I started this one for that purpose. The rest of the post is Phenehas’ question to Neil:
@Neil I also appreciate the professional tone. I am a skeptic regarding what evolution can actually accomplish. In keeping with your demonstrated patience, I’d be grateful if you would give serious consideration to something that keeps tripping me up. I’ve often thought of natural selection as the heuristic to random mutations’ exhaustive search.
A path-finding algorithm can be aided in finding a path from point A to point B by using distance to B as a heuristic to narrow the search space. Without a heuristic, you are left to blind chance. It is said that evolution has no purpose or goal, so there is no point B. It is also claimed that evolution isn’t simply the result of blind chance, so a heuristic would seem to be required. Somehow, natural selection is supposed to address both of these concerns. Nature selects for fitness, we are told, so somehow we have a heuristic even without a point B.
But what is fitness? How does it work as a heuristic? How is it defined? Evidently, it is all about reproductive success. But how does one measure reproductive success? This is where things get fuzzy for me. Surely evolution is a story about the rise of more and more complex organisms. Isn’t this how the tree of life is laid out? Surely it is the complexity of highly developed organisms that evolution seeks to explain. Surely Mt. Improbable has man near its peak and bacteria near its base. But by what metric is man more successful at reproducing than bacteria? If I am a sponge somewhere between the two extremes, how is a step toward bacteria any less of a point B for me than a step toward man? Why should the fitness heuristic prefer a step upward in complexity toward man in any way whatsoever over a step downward in complexity toward bacteria?
It seems that, under the more obvious metrics for calculating reproductive success, bacteria are hard to beat. Even more, a rise in complexity, if anything, would appear to lead to less reproductive success and not more. So how can natural selection be any sort of heuristic for helping us climb Mt Improbable’s complexity when every simpler organism at the base of the mountain is at least as fit in passing on its genes as the more complex organisms near it’s peak? And without this heuristic, how are we not back to a blind, exhaustive search?
Excellent questions.
test
ETA: That is really weird. I tried to repost Phinehas’ comment at UD, and I got the error message s/he has been getting. But without the message, it posted.
Ah, so now Phinehas has managed to post!
Interestingly, something in that post is being censored by the software. I’m going to try it line by line:
Phinehas is trying to post (copied from UD by EL):
TSZ seems unresponsive at the moment. I suppose I can try to continue the conversation here for now.
OMagain:
Next installment attempt:
Phinehas wrote:
Again, I’m not an expert on probabilities, but this doesn’t sound quite right to me. I’d think that any given atom being exactly where it is right now is awfully close to a 100% probability. 🙂 Similarly, if I deal you five random cards, I would think the odds of you having five random cards is pretty well guaranteed. On the other hand, the odds of you having a specified set of cards will depend on the specification (i.e. a “flush”, a “full house”, etc.)
This is like trying to find the dead bulb on a Christmas tree!
Next installment:
Phinehas:
I’ve always preferred dialectic methods, especially when addressing skepticism, since I typically find myself with lots of questions.
At first, it might seem unintuitive to talk about probabilities
after the fact, since, as you say, we get dealt the cards we get dealt. But when you start trying to explain how someone got dealt the cards in their hand, probability becomes helpful once again.
For instance, if I sit down with you for a game of
For instance, if I sit down with you for a game of and (somehow) get dealt three royal flushes in the first three hands, you’d be forgiven for turning back to probabilities to try to consider exactly how I ended up with these cards, even though you knew that any other particular set of cards would have been just as improbable.
Aha – it’s the name of the card game it doesn’t like.
test poken
OK, here is what Phinehas is trying to post:
OMagain:
Again, I’m not an expert on probabilities, but this doesn’t sound quite right to me. I’d think that any given atom being exactly where it is right now is awfully close to a 100% probability.
Similarly, if I deal you five random cards, I would think the odds of you having five random cards is pretty well guaranteed. On the other hand, the odds of you having a specified set of cards will depend on the specification (i.e. a “flush”, a “full house”, etc.)
At first, it might seem unintuitive to talk about probabilities after the fact, since, as you say, we get dealt the cards we get dealt. But when you start trying to explain how someone got dealt the cards in their hand, probability becomes helpful once again. For instance, if I sit down with you for a game of [insert well known card game here] and (somehow) get dealt three royal flushes in the first three hands, you’d be forgiven for turning back to probabilities to try to consider exactly how I ended up with these cards, even though you knew that any other particular set of cards would have been just as improbable.
I’ve always preferred dialectic methods, especially when addressing skepticism, since I typically find myself with lots of questions.
Well, that’s up to you. But I find I ask better questions the more I start off with in the first place. Or, rather, questions that are perhaps worth somebody spending their time answering anew rather then just rehashing some well-worn path.
Not that I’m saying that applies here, to you. It’s just my process. If we can both learn something, all the better.
On another hand, all you have is a set of rectangular objects. We assign values to them to differentiate them from each other and so their appearance in patterns becomes meaningful and subject to mathematical analysis.
Relate this to biology. What is “the full house” in biological terms?
And if all it takes to get a royal flush is to deal the cards N times then that seems to undermine any ID argument. There are many decks, many different games being played simultaneously. That there is a particular winner is no surprise, regardless of how “improbable” that particular winner is.
http://www.talkorigins.org/faqs/dover/day12am.html
Hey! I’m back!
Maybe spam block didn’t like something in my last post? It is over at UD if anyone is interested. In any case, I’m falling hopelessly behind in trying to keep up with everyone else’s posts, so please forgive me if I skim over some here and there. There’s nothing personal, I just want to get to the heart of where my skepticism lives if I can.
Lizzie said:
But I don’t have any skepticism regarding a steady climb toward fitness. Indeed, I can see how such could be described just as easily as a descent. My skepticism involves the climb (steady or otherwise) toward complexity. I’m trying to understand whether natural selection is any sort of an aid in this particular climb. I’m having a difficult time understanding how it could be, since more complexity seems to correlate pretty consistently with decreased reproductive success. Does that make sense?
OMagain offers this:
That is a very good point. However, would it be way off base to suppose if we were having this same conversation that, as an organism, Dino sapiens would be in the same range of complexity as is Homo sapiens? It is the improbability of reaching the complexity of Homo sapiens that I’m trying to imagine, not merely the improbability of reaching Homo sapiens. Does that help clarify?
DNA_Jock:
OK, this is very helpful. I can see how there would be a preference toward complexity, though it seems to me that as complexity grew, this preference would weaken. (Maybe that’s why we aren’t still evolving the way I would expect us to be?) But this doesn’t really take functionality into account, does it?
I know the notion of functional complexity is a bit more difficult to pin down (at least it is for me), but intuition tells me that as something becomes more complex, it will become harder and harder to discover alternative configurations of even greater complexity that are also still functional.
Take the English language, for instance. We know that there are lots of complex possibilities out there as end points, including Hamlet (humans?), War and Peace (Dino sapiens), and Harry Potter (a platypus? 🙂 ). If we start with the letter A and then randomly add, remove, or change letters, I can see how complexity might tend to increase. But what happens when we add the notion of maintaining functionality each step of the way? Suppose we defined functionality as consisting of correctly spelled words leading to grammatically correct English that makes at least as much sense as Harry Potter. As the configuration of letters grows more complex would it be possible for even an intelligently guided process to maintain functionality along the way?
I realize that the functionality of life may be nothing at all like the functionality of language. It could be much easier for life to move about from one functional configuration to another. Or it could be much more difficult. But it appears, at the least, to be a valid consideration, and I am very skeptical about life’s ability to move as freely toward complexity while maintaining functionality as it might move toward simplicity while maintaining functionality.
Does that make sense?
Yes it was the title of the card game you mentioned. I’ve posted your UD post above, with the card game name redacted. Took me a number of attempts before I figured out the problem! Welcome back!
It occurs to me that we might be in violent agreement when all is said and done, so maybe I should just ask outright:
As it pertains to the complexity we see in highly complex and functional organisms (such as Homo sapiens), is there some mechanism in evolution (other than pure, random chance) that would help explain our ability to reach this level complexity?
Or would you more closely agree with UD poster JDH that, “the idea [is] that the entire biosphere has been built up to the current level of complexity by some random oscillations about some equilibrium state?”
Thanks Lizzie, I should have suspected the spam filter sooner. Incidentally, I also discovered that just typing http://www.theskepticalzone.com in as a URL takes me to http://www.theskepticalzone.com/setup.php where I get the message:
Warning: require_once(/home2/qfycpamv/public_html/../seagull/lib/SGL/FrontController.php) [function.require-once]: failed to open stream: No such file or directory in /home2/qfycpamv/public_html/setup.php on line 98
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That also made me think that something was wrong with TMZ instead of suspecting it was just something in my post.
I must get the domain name to point here, one day. If anyone knows how to do it, and can explain it to me in a language other than geek, I will fix it.
It’s been shown, for example, that randomly perturbing proteins usually leaves functional proteins. And dipping into protein space randomly produces functional proteins. I can probably dig some links up if needed.
But the point is, to me, twofold. Firstly, if you don’t maintain functionality you die (let’s say) which nicely partitions off further exploration down that particular path.
Secondly, the demo is down but:
http://zachriel.blogspot.co.uk/2007/10/i-cant-believe-dembski-chose-word.html
Again, this is a well trodden path 😛
OMagain:
Well, it isn’t a path that I’ve trodden-ed…er…gone down before. Thanks for the link. Word Mutagenation is very interesting, though I can’t say I’m particularly surprised by its findings. If you’ll look a little more closely at the point I am trying to make, however, I think you will see that I’m not questioning whether simpler configurations would be able to perform the shorter jumps necessary to hop between functionality. In fact, I was kind of assuming they could. It just seems to me that as complexity grows (especially layers of complexity like grammar, coherence, story structure, etc.), the available functional choices that are lower in complexity will begin to outweigh the available functional choices that higher in complexity. It might be just as likely if not more likely for the complexity of Harry Potter to morph into the complexity of your average young-adult fiction than into the complexity of an Encyclopedia Britannica.
Phinehas,
Assuming for the moment that we primates are descended from an organism like Tiktaalik, can the difference in “complexity” be measured or described in any sensible way?
Or, to ask the question slightly differently, between which two types of organism in a putative evolutionary progression does an increase in “complexity” begin to seem to you unlikely to arise simply by what we think of as evolutionary processes?
Is there an unlikely increase in “complexity” between, say, Pakicetus (a terrestrial carnivore) and a modern whale, for example?
I’m not sure. But I would be pretty skeptical of claims that there wasn’t a vast difference in complexity between the two. 🙂 Wouldn’t you?
I guess this brings me back to my question about natural selection and what it can or cannot do with regard to an increase in complexity. When you say, “what we thing of as evolutionary processes,” are you referring to something other than completely random oscillations or perturbations?
Outside of your language analogy, do you have any reason to believe this? To me, the reverse seems true: {potential higher complexity} increases exponentially with complexity, whereas {potential lower complexity} increases only linearly.
I suspect we are making different assumptions about what constitutes a minimum level of functionality.
Phinehas,
Just out of cuiosity, why would you assume that one vertibbrate is more complex than another? How would you quantify the purported increase and where is it reflected in the genome?
petrushka,
I was wondering the same thing. There are a great many critters around that can do many things that humans cannot do (and some would even kill a human if attempted) so, to me at least, it doesn’t make much sense to state that one vertebrate is more complex than another.
On appearance, and I may be wrong, it seems that this stance is linked to a a mistaken impression of what evolution actually is/does.
The key issue that Phinehas brought up I think still has not been addressed.
What is the point of complexity if simplicity will do? What specific scenarios require an increase in complexity? Appealing to replication error does not seem to address the point.
At the early stage of life’s expansion, I have been told that competition ruled. But logically, there could be no competitive pressure as the vast majority of ecological niches had yet to be filled. So without selective pressure bearing on early life, what was the force acting on organisms driving them to complexity?
Not only that, but what would be the driving force of single-cell organisms being transformed into multi-celled organisms? There seems a vast ocean of difference between them; not simply some fitness peak ( ideal for throwing a multi-cellular party) we can spy with our little eye letting us throw a rope across and shimmy our way to complexity.
And I think this is key. Can an organism, which has spent so much time achieving a modicum of complexity (a complete single cell), travel down the mountain of complexity and then climb back up a different peak? Think about cell division. Imagine the vulnerability of that first separation? How could it survive without life support?
When humans undergo heart surgery, their blood is fed through an artificial circulatory system in the interim when the heart is being operated upon. It took decades to perfect the machinery and process to achieve the ability to do open heart surgery.
Can we suppose the first single cell transforming itself into a multi-cell organism mastered the art of scaffolding prior to division? How could that happen from a darwinian evolutionary standpoint?
Yet there was still competition within those niches themselves – not all the population in each niche is identical.
It seems more probable then an intelligent designer who persists for millions of years giving it a helping hand, no?
Yes, this is a good point, but I think it is really important to keep separate the issues of why complexity appears to increase over time, and why fitness increases over time. The two are almost certainly correlated, but that doesn’t mean that they are causally related. I suggest that they are not, directly.
Let’s define complexity fairly simply and genetically as the number of DNA sequences that perform some kind of cellular function, whether to encode protein, or to govern the expression of protein coding sequences, including suppressing them completely. We don’t know what that number is for a given genome, but let’s suppose for the moment that we do.
Mutations that destroy a functional region will tend to drop out of the population, because they will reduce viability. However, point mutations that result in a slightly different, but equally effective protein, or developmental timetable of protein expression, or protein expression in response to stimuli, may well be conserved in the population. Similarly, duplication of DNA sequences that result in two genes where before there was one, may often have no phenotypic effect, if the expression of those genes is governed by the amount of gene-product generated. We now have an increase in complexity, but no increase in fitness. But gene duplication is one way of getting a new gene – one of the duplicates is now capable of undergoing a mutation that could result in a slightly different function. At which point we have, by our definition above, both an increase in complexity and and increase in fitness.
Now imagine that the environment changes, and it is now disadvantageous for a certain protein to be expressed. What possible mutations might improve matters? One would be a mutation that disabled the protein-coding gene, and we know that this happens. At this point, the genome has become simpler (if we don’t count the junk – because we now have a stretch of junk), even though the bearers of this disabling mutation are fitter. However, there are many other possibilities, and I suggest the majority are add-ons rather than take-offs – changes or additions to regulatory genes that suppress the expression of the coding gene.
In other words, I think it is probably the case (someone might have evidence for this, and it’s certainly testable) – that there are more “more complex” ways for a genome to increase fitness, even when the phenotypic result is a “simpler” organism (e.g. an eyeless fish, or a legless lizard) that “less complex” ways – and even when the “less complex” way occurs e.g. the disabling of a gene, that pseudogene is now a potential new gene.
But if we are talking about phenotypic complexity, then I think the correlation is tighter, and, if anything, argues for evolutionary processes rather than design. A designer can simply say: hey, let’s go back to basics with this design, and red-ink all the stuff that this product simply doesn’t need. Evolutionary processes can’t do that – all that is available is retrofitting – an extra gadget to stop an archaic feature from being an encumbrance, or a tweak to the building process to make the archaic feature (a wing, perhaps, on an animal that is too heavy to fly) useful for something else (swimming – hey, penguins!)
I don’t think your logic works – within-population competition is just as fierce, if not fiercer, than between-population competition. Individuals competing for the same resources are even more competitive that populations that have evolved to utilise different resources. So I think the force is the same – but driving to fitness, not “complexity” – “complexity”, I suggest, is the epiphenomenon.
A good and interesting question. There is quite an interesting literature on that. As well as some interesting literature that suggests that colonies of even modern single-cell organisms, like bacteria, in some ways behave like multicellular organisms, with chemical signalling occurring between population members. Indeed even ant colonies behave in some ways more like single organisms than a population of individuals.
Well, this is where the simple 3D picture of a mountain range needs expanding to multiple dimensions. Yes, we know that populations can get across substantial “ravines” (that’s what Lenski’s AVIDA experiment showed) by evolutionary means, but not vast valleys. But the point is that fitness space is very high-dimensioned – so what is a valley along one dimension may be a horizontal ridge, or even a gentle slope, along another. In less metaphorical terms, a subset of a population that is at a peak of fitness by maximising the exploitation of a certain set of resources in its current environment may still evolve by “discovering” how to utilise a different set of potentially available resources – larger seeds, for instance, or higher fruit.
As for cell division – the dividing i.e. replicating process must precede any evolution at all. Darwinian processes can only occur in a self-replicating population. So that question is really an OOL question, not a Darwinian question. But it is interesting that the most promising ideas about OOL at the moment are those that posit the co-evolution of lipid vesicles (bubbles of lipids) which we know can grow and divide, just as soap bubbles can, in a “soup” of self-replicating polymers which can become encased, and thus concentrated, within the vesicles. But nobody claims to be there yet.
Well, cells divide anyway – whether the whole organism is the cell, as in bacteria, or whether the cells are the cells of a multicellular organism. So watching bacteria divide is very similar to watching the cells of an organ divide. The big difference is that within a multicellular organism, the position of the cell in the colony affects the gene expression within the cell, so outer cells may differentiate into “skin” while inner cells do something else, the differentiation being modulated by chemical signals between cells. But as I said, chemical signalling between cells also happens within colonies of bacteria, so there is not even an absolute step-change between a bacterial colony and a proto-multicellular organism.
^^This^^,
also
Dictyostelium
Phinehas,
Before I attempt a comprehensive answer, (or others supply answers) I’d like to know – would you consider a sparrow more or less complex than the dinosaurs that were apparently its ancestors?
Complexity has no point. If there were some kind of inner drive toward complexity, then single celled organisms would not remain the dominant form.
Evolution is in part a drunkard’s walk. It has no target direction, but over time any genome departs from its point of origin. Some departures may appear to be more complex than others, and if they survive the become virtual points of origin.
Vertebrates share almost all the same genes for protein coding. Most of the “hard” evolution of new proteins was done by bacteria, consistent with their high reproductive rare.
@OMagain:
For some reason, I’m always a bit taken aback when I see negative arguments for Darwinian evolution. Perhaps it is partly because I expect there ought to be enough positive scientific evidence to support something as provable as gravity that there would be no need to resort to negative arguments. More likely, it has to do with the number of times I’ve seen the notion of considering design as the best among competing explanations poo-pooed as an invalid inference. In any case, it does little to assuage my skepticism.
Yes, I don’t think negative arguments are needed, unless there is a positive alternative on the table. Then, differential predictions of the two need to go head to head.
This often happens within evolutionary theory, but so far, not between evolutionary theory and some quite different theory, because ID is a bit short of differential predictions. ID proponents will dispute this, but I have yet to see a fully operationalised one (although “front-loading” looked promising for a while).
Phinehas,
When the positive evidence is resolutely ignored, then pointing out the absurdity of what logically must be the alternative seems like a reasonable action.
As Lizzie notes, were we able to compare like to like and derive which has the most productivity re: predictions then that would be the way to go.
I’m not making a negative argument for Darwinian evolution. The fact is that IDers don’t want to address the idea of having a designer that persists for millions of years because that’s not really any designer we’re familiar with. And ID is all about extrapolating from known to unknown. And you can’t extrapolation from humans who live tens of years to something that lives for millions.
If you want a positive argument for evolution read CMI.
I find this very odd. Can you give me an example of such an occurrence?
What I mean is that as far as I’m aware we’ve never been in a position where “design” has been shown to be the best explanation among competing explanations.
Can you say what “design” you are thinking of, what were those competing explanations and how it was determined that “design” was the best explanation?
What seems more likely to me is that you have read this has been done at UD and assumed it was in fact done.
But I’m unaware of such. Can you explain what it is you are thinking of here with this claim? Can you walk me through this process of determining design? Ideally you would also determine the FSCO/I as a side effect.
Petrushka:
I don’t think I would assume that any one vertebrate was more complex than another. However, I don’t tend to look at Homo sapiens as just any old vertebrate. It seems to me that there are some pretty significant qualitative differences between Tiktaalik and humans, and I tend to suspect that, even if these qualitative differences can be accounted for by purely quantitative means, you’d probably be talking about some pretty extreme quantities.
It is for similar reasons that I assume humans are vastly more complex than computers, I suppose. And I suspect much of that difference could be down to software as much as to hardware. As someone who is involved in the development of software, I am keenly aware of its complexity, which brings me to:
DNA_jock:
I think to some extent I am also looking to my experience with complex software to inform my intuitions. A company that has used the same game engine year after year to crank out (e.g.) a sports title can run into issues with its code becoming more fragile and brittle. There are competing goals to keep up with advancing technologies (the environmental niche?) while at the same time to get the needed income by putting out a new title each year. The result is “spaghetti” code that exacts its own cost on productivity. Each year, the company is faced with the choice to bite the bullet and undertake the massive effort of jumping to a island of functionality that is getting further and further away, or to continue with a more evolutionary approach that only makes gradual changes.
And we’re talking intelligently designed “spaghetti” code here, where there is at least an option to eschew gradualism to various degrees.
Phinehas,
Then why would Behe poo poo the claim that demons ate my homework? Negative arguments are reasonable when used against a claim which is preposterous.
I will stipulate that for decades after “Origin” evolution was the preposterous claim. But the weight of evidence has tipped.
The same could happen with UFOs or ESP. Evidence has a way of overcoming skepticism.
But is a decision based on the weight of evidence, not on certainty. Which is why lots is better than none.
Yet life never “bites the bullet” and jumps to a new island of functionality, does it?
It continues with a more evolutionary approach that only makes gradual changes. Therefore what we see in life does not support this aspect of ID in any way whatsoever.
OMagain:
What positive evidence was it that Steve was resolutely ignoring? Or were you talking about me? That seems a bit unfair, since I’m am simply trying to give honest reasons for my skepticism.
In any case, I don’t find the alternative nearly as absurd as you make out. (I’m trying to be nice here and not call it a straw man. 🙂 ) While we may never have observed a single intelligent designer persisting for millions of years, we certainly have seen intelligent designers that are self-replicating and have the ability to pass on knowledge and intent to follow-on generations. We’ve also seen designers who can plan and program software that continues to run well after they are gone.
But that’s really beside the point, in my mind, if you’ve got enough positive evidence to convince skeptics as well as believers.
OMagain:
Setting aside that you might be assuming your conclusions, I think you may have glossed over the context of my analogy. Petrushka was asking the source of my intuition that more complexity often leads to more fragility and that a kind of brittleness can set in that limits more complex choices and applies pressure to move back toward the kind of simplicity and elegance that is agile enough to meet changing environmental needs. (In other words, complexity can tend to increase the distance between islands of functionality.) I gave an example from my own experience.
It’s a good intuition – in human designs, more complex often does lead to more fragility, which is why Iike my Dualit toaster.
But I think it’s important to nail the metaphor down here – how are you defining “complex” in the context of an organism? And how are you defining “fragile”? I ask, because in many contexts, diversity leads to robustness, not brittleness, and in some contexts, diversity could be characterised as complexity.
Complex systems often contain redundancies that render them more, not lest, robust, than an elegantly minimalist system. So I don’t see complexity as a bar to fitness, just a more likely way of getting there, for an evolutionary process, than simplification.
As for the distance between “islands of function” – co-option is one way that evolutionary processes traverse “solution space” – which is less available to a simply system than a complex one.
I’d love to hear a more plausible ID alternative, but ID supporters seem reluctant to actually commit to such. I’m simply inferring what must be the case from the claims ID supporters make.
I was talking about you, and yes perhaps it was a little unfair and so I apologize for that. But it seems to me that me and you could spend the rest of my life reading the “positive evidence for evolution” whereas I’ve already read everything ID has to offer (most of the top tier ID books) and found it, well, not very compelling.
So if you find that positive evidence unconvincing that’s fine. But as I keep saying, if you’ve not read it you can hardly find it convincing can you?
These are all true. But it is also an ID claim that the universe and the solar system are configured specifically for life. And we’ve no experience with those sorts of designers 🙂 yet ID/UD conflates the two together – there is no gap between the designer of protein domains and the designer of the universe at UD. KF in fact often invokes both situations in the same comment.
So be skeptical, I encourage it. There is lots to be skeptical about re: Darwinism. That book is not complete. But if you are going to apply the same standards to both then logically ID does not even rise to the level where you can be skeptical about it’s claims.
Lizzie:
Wait. Where did we get an increase in fitness? (I missed where fitness was defined, but I’m assuming we are still talking about reproductive success.) Are we assuming that the capability to undergo a mutation will automatically result in greater reproductive success? Or that even if we make it to a slightly different function, this will automatically result in an increase in reproductive success?
I’m still really having a hard time seeing the correlation between complexity and fitness.
Perhaps the more complex something is the more “options” are available a single step away. And each of those options lead to other options, most more complex, fewer to simpler states. This was already noted in this thread and I found it very convincing.
WJM at UD
And what is the answer to the question that ID asks and Darwinists do not WJM?
Would it be “yes” by any chance?
In the same way that “design” is an “explanation” for the flagellum?
Color me unconvinced.
Well, caught, that was carelessly put on my part 🙂
My point was that once we have a duplicate we have a potentially rich patch of genome that might one day result in an additional gene that does contribute to reproductive success, and would then be an example of greater complexity and greater fitness.
But I agree that the correlation is loose, and not causal – it’s the point I am trying to make. Complex things aren’t necessarily fitter, but the same processes that result in increased fitness also tend to result in greater complexity. Just as shoe size doesn’t cause tallness, but the things that cause tallness fairly reliably also cause big feet 🙂
OMagain:
Maybe I’m not understanding how evolution works, but I’m just not seeing how more “options” for changes that have not yet been instantiated could possibly increase reproductive success in an organism.
Perhaps I’m just a wee bit more skeptical than you are?
They don’t, but they increase the evolvability of the population.
Perhaps. Then I would ask “what is your current personally accepted explanation for the issues being discussed in this thread”?
I don’t know is a perfectly acceptable answer. But then I will ask you to rank the options available in the order in which you find them most to least plausible, and then ask you to justify that list.
Phinehas,
Brittleness is an observed fact in some populations. Witness endangered or recently extinct species. Most known species are extinct. The layman’s term is overspecialzed. It happens in all systems that respond to selection, including humans and human organizations.
Lizzie:
OK, but how long do we suppose that potentially rich but currently useless patch will hang around waiting for Gould’s “almost, but not quite, never?” There’s also every chance that the resulting gene (should it ever manifest) will be negative, though we’d assume that organism would be weeded out and not significantly impact the population. On the other hand, there’s an even greater chance that the resulting gene (should it ever manifest) would be neutral, in which case it could well spread throughout the population. It even seems possible to me that the added complexity could be viewed as a very slight decrease in fitness that (for the present) would not adversely affect reproductive success, allowing it to spread through the population, but as the described process repeated and complexity grew without increasing fitness, rising brittleness and fragility could reach a point where the accumulation of slight decreases in fitness would reach a tipping point.
So it seems to me that greater complexity without greater fitness is at least as likely an outcome as greater complexity with greater fitness, isn’t it? Conceivably, greater complexity with a decrease in fitness is also a plausible outcome. (Not only plausible, but as pointed out before, something that seems pretty apparent when we take a high view of all organisms and compare their complexity and reproductive success.) All of which leads me back to trying to figure out how complexity and reproductive success could possibly be correlated.
So I ask you (nay, I beseech you 🙂 ): Does it appear that my skepticism, at least at this point, could possibly be reasonable? Whether valid or not, are my objections at least understandable? Do I in any way demonstrate a lack of willingness to consider that I might be mistaken? Might my motivations be characterized by an honest search for the truth of the matter?
If I’ve given you cause to question your beliefs, not about evolution, but about those who are skeptical regarding what it can accomplish, then I would consider my visit here fruitful, whether I ever change anyone’s mind or not. I think it is often a lack of doubt rather than a lack of faith that tends to get in the way of progress in these sorts of discussions. I think there is more than enough faith on both sides to go around.