The challenge, for all and sundry but especially for “Darwin doubters”, should you wish to take it, is to submit a one-paragraph summary of the theory of evolution. The idea is to see if you understand it well enough to fairly summarize the theory so that you pass as a proponent of evolution. We also need some examples from proponents to test the null hypothesis!
To ensure anonymity, please submit your paragraph by private message to me or another admin and we will add it in edit. (Or email it to me at alanfox@free.fr if you prefer.)
Speculation and divination are enouraged in the comments!
ETA some degarbling!
First contribution:
The Theory of Evolution (hereafter referred to as just evolution is generally credited to Charles Darwin. In his book, Origin of the Species, he described his observations regarding finches in the Galapagos Islands. He noticed that living organisms, when they reproduce, are reproduced with slight modifications. In essence that organisms descend with modification. The first crucial part of evolution is this basic idea. What we now refer to as descent with modification. Gradually, over much time, continual modifications are made to generations of descendants, and after much time, the descendants may be quite different in function and appearance than their ancestors. The first part of this theory was established prior to our current knowledge of DNA and genetics. After the discovery of DNA, and as we learned about how genes are copied, evolution was confirmed because we learned in fact that genetic s are not copied perfectly. Instead there are slight changes, we call random mutations. We now know that Charles Darwin’s ideas about descent with modification were correct and more precisely we know that those modifications happen through random mutation. The second crucial part of evolution is the idea of natural selection. When random mutations happen, they are mostly nonsignificant and have no bearing on an organisms ability to survive in their environmental niche. However, sometimes the random mutations are negative and those specimens die out quickly and don’t reproduce. For instance, albino rabbits are more easily seen and captured by the foxes than are rabbits that are brown. In other cases though, the random mutations result in positive changes to an organism in their given environmental context. These mutations allow the organisms to be more fit for their context and thus they are more successful at reproducing. Gradually over time, natural selection weeds out the less adapted versions in favor of the newer adaptations. An example of this can be seen in the black and white moth scenario in the UK. Together, Random mutation and natural selection along with ‘deep time’ make up the heart of the modern synthesis of evolution. The theory continues to readjust slightly over time with additional research. For example, recently, a minority of scientists (Kimura, et al) have emphasized simple descent with modification as the primary driver of evolution, though not totally discounting natural selection. In essence a neutral drift of the species mostly. There are other slight variations with the models, for instance Stephen J Gould famously proposed a punctuated equilibrium model as an alternative to the ‘gradualist’ model. In neither of the mentioned cases though was evolution rejected. Instead, proposed variations to the theory were given. There are generally some very convincing evidences for evolution. The fossil record and its various layers support the theory of evolution. The age of the universe supports evolution. Vestigial features such as the hair of the human arm standing on end when we are scared or cold provide compelling examples. Junk DNA provides powerful evidence of evolution. And the close relationship, DNA wise of chimps and humans provide strong evidence for evolution. The origin of life, abiogenesis, is generally considered outside the conversation of evolution and not strictly speaking part of evolutionary theory. Evolution gives a clear model for explaining the diversity and similarity of living things across the earth. Contrary to some opinions evolution doesn’t necessarily make any statement about theism or atheism.
Second contribution:
The theory of evolution is that biological organisms develop from one physical state to a different physical state by incremental steps through selection of successfully reproducing members of a population. Those successfully reproducing being due to mutations affecting members of a population and those members gaining a advantage in a environment of the moment. The mutations being the important element for biological change may mean also that selection is not needed in a population and so new populations may simply occur upon mutations alone. The evidence for the theory is from a system of close attributes in organisms demonstrated by a tree formation. These attributes are used to show a spectrum of biological relationship and so common descent to be demonstrated. Genetics and the fossil record are also essential evidences and based on attributes showing a spectrum of divergence. Other evidences based on comparison of attributes also are included. Starting from a hypothesis the accumulation of evidence and general explanatory weight has turned the hypothesis into a theory in biology. Within the evolutionary biology community there are important or notable differences in ideas on aspects of evolution however the core concept is a foundation.
Third submission:
Whether it is a court case or science, the capabilities and limits of causes of specific effects are crucial to deciding whether or not there is good reason to doubt the alleged cause or causes. Evolutionary theory lives or dies on the evidence of the specific effects caused by its capabilities and limits, as should any other claimed cause of life and its diversity. In simple form, evolution is caused by reproduction, which passes inherited information from parent to child, or from single cell to daughter cells, with considerable fidelity, but also with changes in that information called mutations. Detrimental mutations tend to be weeded out by natural selection, while natural selection tends to retain beneficial mutations, and over many generations intersecting and additive beneficial mutations may lead to new features, such as flight. Much more happens in evolution, like neutral or near-neutral mutations, bottlenecks, and genetic isolation (or not), but natural selection tending to eliminate what does not lead to reproductive success and favoring what facilitates reproductive success is usually thought to be the most important process. With these evolutionary processes in place there is considerable scope for impressive change over long periods of time, but there are also important limitations to it that mark evolved life with the evidence for evolution. Notably, while there is some genetic flow between reproductively separated lineages, especially in prokaryotes, polygenic traits are quite unlikely to be transferred to, for instance, vertebrates. Vertical transmission of DNA information predominates in most eukaryotes, and is quite evident in prokaryotes as well. The relative lack of portability of information across separate lineages shows up in the vertically derivative genomes of vertebrates in general, which is seen as nested hierarchies in taxonomy. The limitations of evolutionary processes apparently produce the patterns of life. An interesting example is to be found in the three types of flying vertebrates, bats, pterosaurs, and birds, which all share obvious yet fairly distant homologies, but whose flight adaptations are entirely uninformed by each other at all, apparently due to the fact that all three groups had diverged before each group evolved flight. The same evolutionary limits mean that birds do not have the fine auditory bones that evolved in mammals, while mammals do not have the improvements in eyesight that evolved in birds, such as the pecten (nor do mammals have the more efficient lungs of birds). Vestigial organs are a peculiar case of information retained that is no longer useful for a specific purpose (but may have other current uses), such as the tiny bones of the human coccyx that apparently evolved from tail vertebrae. The general trend of the fossil record is also what would be predicted by evolutionary theory, with amphibians needing dampness evolving first from fishes, then reptiles evolving for drier climates, while mammals and dinosaurs (including birds) evolved insulation for colder areas (among many other changes). “Transitional” forms like Archaeopteryx reveal the incomplete and inefficient adaptations expected from evolutionary processes that are mostly incapable of all but incremental change. The specific patterns and evolutionary developments visible in present life and in the fossil record point with consilience to a specific set of processes that we see happening today, the evolutionary processes of inheriting DNA information with some variations in that DNA, along with natural selection tending to retain reproductively helpful changes, while tending to eliminate reproductively harmful changes.
Fourth submission
The theory of evolution holds that there has been, and continues to be, change in form via change in the genetic makeup of organisms during the succession of a lineage – summarised as ‘descent with modification’. The primary source of these modifications is provided by mutation, arising from copy and repair errors and DNA damage, but also with significant contributions from recombination, gene transfer and transposition. Many changes are lost, but some become fixed, an inevitable consequence of the blind resampling process that is involved in a succession of generations in populations of finite size. Where a change is neutral, it may become fixed in a population through genetic drift alone. Where non-neutral, both drift and selection are involved. The change affects its own survival in the population, by influencing the rate at which it is passed on to descendants, when compared to the neutral expectation. Detrimental changes are more likely to be lost, and this will occur more rapidly on the average than neutral ones. Conversely, beneficial changes are more likely to become fixed, and again this is likely to happen more rapidly than the neutral case. These latter processes constitute the modern version of Darwin’s principle of Natural Selection, which lacked a sound genetic basis when first proposed, but nonetheless articulated the basic requirements of variation and excess of production over carrying capacity.
Within sexual populations, interbreeding tends to maintain an entire population in step, but where gene flow between such populations is reduced or eliminated, divergence is inevitable, leading to the phenomenon, at a moment in time, of multiple fixed and distinct types derived from the original single population. With increasing time, ongoing divergence leads to broader and broader taxonomic classifications with greater and greater difference between them, but all tracing back to simple population-level splits at varying depths in the time series.
No, jester boy, WHICH evolutionary theory. You can’t even manage to accurately represent the position you’re trying to mock. Oh, wait …
As I see it the “theory’ of evolution, I don’t agree its a scientific theory, is not about details but about major concepts. So, i think, the submissions should not include al the hypothesis within the hypothesis of evolution.
Its not a summery otherwise.
A summery should hit the important ideas.
There are not multiple theories of evolution. there is only one theory of biological change called evolution. The rest is only variations on EVOLUTION.
Too many folks here keep saying its plural. Nope.
If there are no competing theories of evolution then “The Theory of Evolution” may as well be dogma. Oh, wait …
What is “The Model of Evolution”?
If there is such a thing as “The Theory of Evolution” then it ought to have an associated model, and not a plethora of models, because a plethora of models would indicate that there are in fact multiple theories of evolution.
Mung,
What competing theories of evolution would you like to offer for serious (or, for that matter, frivolous) consideration? ID, I’m aware of, but that is hardly what people mean when they say ‘there are SOOOO many theories of evolution’.
Is this supposed to be a serious question?
Mung,
Yes.
As far as I can see, the capital your colleagues are trying to make out of this is that mainstream evolutionary theory has just too many theories, with an implication that they are incompatible. But when pressed, you clam up, or come up with something completely non-controversial and entirely compatible, such as selection and drift.
I have long ago conceded that, if people see (say) drift and selection as completely different theories of evolution***, that might be grounds on which to make the case – though it hardly seems worth the aggression and exasperation that seems to accompany the jibes from the likes of Gregory, phoodoo and yourself.
*** I actually don’t think they are separate – if selective coefficient is treated as a continuous random variable; both the biased and unbiased components flow from that simple fact inseparably, albeit varying in their relative contribution to frequency change according to selective strength, population size etc.
Hmm! On that basis, taking speed as a continuously random variable, standing still is the same as running very fast!
/devil’s advocate
🙂
It looks like submissions and divinations have dried up, so I’ll reveal my sources this evening.
What we’ve learned is that Alan Fox failed to administer a successful Ideological Turing Test because he didn’t set up a coherent one in the first place. Note that he didn’t even call it an ‘ideological’ Turing Test, but rather an ‘Evolutionary Turing Test.’ 😉
This is doing largely what Alan Fox wants to do anyway, in separating the wheat from the chaff. http://www.patheos.com/blogs/unequallyyoked/ideological-turing-test-contest
Gosh that’s supposed to be so hard to DISPLAY? One must be BLIND to miss the many THEORIES that take the name ‘eVolution.’ Such a simple challenge from a myopic atheist who promotes ideological evolutionism, in addition to *just* evolutionary biology!
Let’s just take an example from a next week event. University of Cambridge comes in on my ‘authority’ list just slightly higher than ‘Allan Miller’. 😉 And I know from experience of meeting Andrew that he is full of it on this topic, just like Allan Miller. But there you have it: “evolutionary social sciences now constitute a mature field of research.” http://www.crassh.cam.ac.uk/events/26934
Does ‘evolutionary social science’ in any way put forward a *DIFFERENT KIND OF THEORY* from ‘evolutionary biology’, not just a different DEGREE of the same thing?
Evolutionary philosophy doesn’t really count as a ‘thing’ anyway to you, right, because this whole conversation is about ‘strictly biology’ and nothing more than biology, right? Haven’t yet heard of ‘literary Darwinism?’
Here are some of your options: 1) you were only really talking about biology, not social sciences; 2) you personally have *never* used the term ‘evolution’ outside of a ‘strictly biological’ context; 3) you always correct people when they use the term ‘evolution’ outside of a ‘strictly biological’ context; 4) you advocate for the restriction of the term ‘evolution’ to ‘strictly biological’ or ‘strictly natural’ scientific analyses.
Do any of those reflect your thoughts or position?
Gregory,
Option 1. I was quite clear that I meant biological evolution, and I think it’s pretty clear that the critics who are wailing about it mean that too. Sorry if you missed that. If people are confused about a multiplicity of biological evolutionary theories because of the existence of a sociological evolutionary theory, I’m not really sure how I can help them.
Alan Fox,
Hmmm! Poor analogy!
If a fixed allele is marginally detrimental, we say it was ‘fixed by drift’. If it is marginally beneficial, we might loosely say it was ‘fixed by selection’. But it wasn’t really. It too was fixed almost entirely by drift, with a small contribution from cumulatively net-positive influence. Indeed, because the negative s is a random variable, which means it has a distribution, there can be occasions when it too has a positive influence. It’s just that the centre of the distribution is to the left – it’s net negative.
Selection is a bias on drift, is IMO the ‘correct’ way to look at it.
Yeah, why would anyone want to face any of those *OTHER* ‘evolutionary theories’? Y’know, the ones you don’t consider as ‘others’ and appear not to even think is possible or allowed to think. I didn’t think you’d actually man up to face #2-4, Allan. 😉
So, in the end, before the beginning of Alan Fox, one needs to face the threat of biologism (c. 1940s-50s to present) with its claimed monopoly over ‘proper usage’ of the term ‘evolution’ and the ‘evolutionary theories’ that may or may not use it. Leave the (largely USA protestant white under-educated ‘evangelical’) nitwits to contend there is *NO* evolutionary theory, but take a more difficult test by taking a stand against non-biological evolutionary theories, which quite obviously exist and can be analysed for their efficacy or lack thereof, etc.
And of course, this attack on the ideology of EVOLUTIONISM will be humourously pretended as ‘upstage-able’ by a foxy skeptic-wizard showing his ‘gotcha’ decadence defense of OTTeVo. Those are TSZ priorities! What happens though if I’m skeptical of OTTeVo & hold extraordinary cards that demonstrate why?
No help for the ‘skeptics’ (can’t really call it a community, without a soul) who can’t escape from the revealing of multiple evolutionary theories across a range of fields, as well as abuses, distortions and yes even frauds (eVo-psycho – wanna go?). What a time to prepare oneself for the turn to trans-evolutionary change!
How many evolutionary theories would you like with those ‘Freedom Fries,’ mr. Fox? We got lots – pick your field or discipline! Chances are good ole’ evolutionists’ll be there scheming to spawn their universal evolutionism. Just a theory you say?! Oh, Mary Midgley, what would she say? 😉
Afterthought: Mary Midgley vs. Elizabeth Liddle, the long absent un-godmotherly landlord of this gang of ‘skeptics’ would be an absolute hoot! Midgley isn’t ‘religious’ herself (though she does have a worldview and myths that she lives by), but would shred the evolutionary mythology that unknowing people here take for granted. Could someone set this up? LOL!
Skeptical journalist: “How many evolutionary theories are there?”
Mary Midgley: “Apparently, as many as the ideological evolutionist needs to convince you there’s just one, while denying they are an ideological evolutionist.” =D
Gregory,
Absolutely nothing stopping them. It’s simply that the general criticisms on this score, and hence the responses, are specifically in the realm of the biological.
Gregory,
Is that an actual conversation or an imagined one? Google couldn’t locate it. But Midgeley too in that snippet appears to avoid giving any kind of detail, beyond allusion to a multiplicity and the existence of ideological commitment to its denial.
It doesn’t take much ideological commmitment to deny a position whose proponents refuse to articulate in anything but the vaguest of terms.
OK, I’ll make my suspicion public. Probably dead wrong, but my guess was that Glen wrote #3. The other person who crossed my mind (because of the mention of court cases in the opening graph) was petrushka.
Well, I wasn’t being entirely serious. Or, possibly, at all
I get that. Statistical bias.
Absolutely. Drift without bias achieves what?
Alan Fox,
I know, I got that!
Evolutionary change.
Well spotted!
The first submission was from ToE skeptic and occasional poster here, Jackson Knepp.
The second submission was from Robert Byers! Well done, Robert.
The third submission was indeed Glen Davidson.
The fourth submission was Allan Miller.
Possibilities !
She made a fool of herself criticising Dawkins for his analogy of the selfish gene, thinking he thought molecules could really be selfish. I guess she could say almost anything. Who would care?
I get that too. Clearing the decks for new alleles. Drift on its own? For ever? What happens?
Alan Fox,
It doesn’t happen on its own. But I guess if it did, there would eventually be just multiple copies of one genome [eta – which would also be true with selection, only quicker]
If I haven’t mentioned it recently, Allan Miller rocks, and I want to read his book.
Agreed!
Of all the options to comment from my post above, Alan Fox, the skeptic evolutionist goes for the personality, insults & dismisses Mary Midgley in favour of Richard Dawkins’ analogies! Ouch on Alan. 🙁
As for the ‘selfish gene’ analogy and what Dawkins didn’t think a ‘self’ is (certainly not vitalism or soul-ish), well, then he shouldn’t have used the term ‘selfish’ in the first place. If he (& most of us) didn’t think ‘genes’ (still loosely defined) have ‘selves,’ then faulting him for suggesting they do isn’t exactly the critic’s fault! For that matter, shouldn’t he not only feign celebrity with the ‘high-jacking’ of online memes, but also come out with more than an ‘I was just joking’ post-mortem on ideological ‘memetics’?
Doubtful that will happen. But hey, loose analogy pretended as being tight, rational thinking isn’t exactly a new technique for skeptics in the doubting pool. We see through such foxy strategy as self-serving nonsense.
“Well done, Robert.” = foxy admission of skeptics being schooled by a YECist! ROTFL!!
UD thread has over 100 posts on its Ideological Turing Test. LOL! Major evolutionist fail at TSZ.
(Desperate aside: “But there really *IS* just a single, solitary, monolithic evolutionary theory” … because I say so wAHaha … and I’d have gotten away with it except for that darn
creationist, IDist, theistic evolutionist, evolutionary creationisttrans-evolutionary change diplomat!”)Gregory,
Gregory, would you please start a thread highlighting TEC’s novel (not part of Modern synthesis / NDE ) predictions?
Thanks!
walto,
Me too! I should probably get cracking …
Gregory,
Haha! That settles it then. They probably get more Google hits too.
The selfish gene isn’t really a gene either, in the more commonly used sense. Dawkins explains this too. I think he overestimated the intelligence of some of his potential readership.
Gregory,
maybe there is, maybe there isn’t, but so far the people saying there isn’t seem incapable of saying anything more substantial than ‘there isn’t’.
Perhaps if I Googled it, I’d spot something and think “Ah! That’s what Gregory means”.
C’mon guys, try a bit harder to salvage a win, or at least not a total failure out of Alan’s little misnamed experiment. It’s really almost working so far 😉
OTTeVo is shown as empty talk. “Oh yes, so there *are* multiple evolutionary theories. But there is only OTTeVo in biology!” Wink, nudge =)
So, now it seems all that’s left is for Alan Fox to provide the OTTeVo in biology, which everyone else was trying to imitate. I’m sure everyone’s waiting for bait, which Alan is only going to pull away now, claiming a hypothetical, fictitious, ‘experiment’ without a soul.
He’s going to first say something like *IFFF* there were only a “single, solitary, monolithic evolutionary theory”, then perhaps…
…anything rather than provide that SINGLE definition himself, even just in biology.
It’s hiding & give no OTTeVo definition time for foxy skeptics!
“The theory of evolution is wrong, and I’m going to….complain on a blog about it!”
Not the brightest knives in the drawer.
Gregory,
I rather like submission #4 above, myself – the guy who doesn’t know the meaning of the word ‘paragraph’. Is there something he missed, allowing for the precis nature of the medium? Or is the fact that more than one ‘thing’ is mentioned the real cause for concern?
The same thing as drift with bias. Drift.
I beg to differ. Perhaps Joe F. will weigh in.
This view of drift makes it appear as if drift is just unbiased selection, which is nonsense, or that drift is what happens in the absence of selection, which is just not true.
An allele may be under selection, positive or negative, and still be fixed in the population for reasons that have nothing to do with selection. One of those reasons we call drift. Are there others?
Mung,
Neither of those follows from what I wrote. I did not say that drift only applies in the neutral case, but that selection adds a bias to the stochastic process. ie, it does not replace it.
The fundamental process is one of population resampling. That inevitably has a stochastic component. Selection is a skew in the stochastic component.
It only has nothing-to-do-with selection in the neutral case. In the non-neutral case, it has something to do with both selection and drift. Selection can be turned off; drift cannot.
Drift is the reason a detrimental allele can become fixed. We might choose to say ‘it’s all drift’ in that case, but I would argue it is also a substantial contributor to the fixation of beneficial alleles. A marginally positive coefficient alone is not enough to guarantee fixation. Evolution is not deterministic.
Mutation, conceivably.
The real world is complex, apparently too complex for you.
[only just noticed this so apologies for late response]
That’s a bit harsh, Gregory. I put up this thread because another commenter, Tomato Addict, suggested it. It seemed a fair suggestion to test the reciprocal idea that ID proponents attack evolutionary theory when they don’t really understand it. Barry Arrington launched the challenge that ID skeptics attack “Intelligent Design Theory” without understanding it.
We only know what might prove interesting to our members in hindsight.
You need to spell out your acronym.
Spell it out.
Is this your ideosyncratic way of asking for a restatement of the core tenets of evolutionary theory in my own words?
You need to be specific. Do you want the whole theory, a one-paragraph summary or a definition? Would some links to some of the mountain of resources available on the internet suffice? And to clarify, the adjective “biological” should be understood as attached to any reference to evolution that I’m making.
I can’t make sense of this.
Luckily for us! 🙂
Ding, ding – we have a winner! There are only multiple theories of evolution *OUTSIDE* of biology. Thanks for explaining that, Alan Fox. Only silly rabbits couldn’t have known that!
There’s just a small problem of ideological bias:
BY DEFINITION NONE OF THE ‘EVOLUTIONARY THEORIES’ OUTSIDE OF BIOLOGY COUNT.
So we see foxy biologism in action. And then it will be refusal to consider reflectively what biologism means because thinking is difficult for some skeptics.
All the while, we’re still waiting for that OTTeVo (read up in the thread for acronym) in biology please, foxy. Just add it below, so that we’ll see how monolithic and single theory consensus-testable it is. Because as everyone knows, while Alan Fox is not a biologist, not trained in the field which he is now claiming to KNOW the OTTeVo, even still this doesn’t mean that he cannot spot a bad textual argument, and that is just as valuable as knowing biology itself 😉
YEC fanatic Robert Byers outfoxed TSZ!
This is hilarious, almost on par with the silly “evolutionary social sciences” conference mentioned above. By Alan’s def’n that doesn’t count as ‘scientific’ nor does it count as ‘evolutionary theories’ although they use the term ‘evolution’ widely in their work, which is funded by major universities, like the small one in Cambridge.
“Doesn’t count in my skeptical authority book,” twits a TSZ moderator!
Gregory,
NOT WHEN YOU’RE TALKING ABOUT THE BIOLOGICAL THEORY, NO.
Is this Rumpelstiltskin dance entirely because you’ve manage to elicit a concession on something that has never been in dispute in the first place? Well done. Why in heck people are mithering evolutionary biology about theories in other fields, I cannot imagine. I thought critics were complaining because there were so many (or not any) biological theories, and they were all confoosed.
Allan Miller,
With all the *butthurt* (that word is ‘traditionally’ accepted at TSZ), it sadly sounds like you’re a biologist, Allan Miller. Is that correct?
The number of biologists who think the world revolves around them seems to be rather high nowadays.
Hmmm…. maybe if it read “Take the Ideological Biological Evolutionary Turing Test” that would be more accurate?
But that would probably be too clear, coherent and specific for butt-hurt evolutionist-skeptics to take credit for. It’s a tough world to take a position when doubt is so cheap to buy nowadays. And btw, what a *utopia* it would really be for humanity if everyone became a biologist because they are so sexy and intelligent just because of what they do.
“It even sounds titillating just to say it ‘bi-o-lo-gism.’ I’m almost ready to faint.” 😉
Genetic drift results from random births, random deaths, and random Mendelian segregation. (The word “random” here means that we can most sensibly model it as random, not as a judgement about determinism). Natural selection occurs when genotypes have different fitnesses, different products of viability and fertility. Fitness is (in simple discrete-generations life cycles) the expected number of newborn offspring per newborn of that genotype. (Actually it is best for it to be half that if the organisms are diploid, for obscure technical reasons).
The situation is very much like modeling movement of particles in a solution. Gravity will pull particles down, and Brownian Motion will make them wander randomly. Their distribution will be the net result of both.
We can imagine having no natural selection, if all genotypes had equal fitnesses. It is harder to imagine having no genetic drift, but as the population is taken to be larger and larger there is less and less of it. Neither force is a subcase of the other.
And someone will probably write in to say that there is no such thing as selection (it’s just the result of unequal viabilities and/or unequal fertilties) or that there is no such thing as random genetic drift (it’s just individuals happening different survival or reproduction). That argument is a waste of time — physicists do find it useful to discuss Brownian Motion, even though it is just molecules banging together.
Gregory,
Feel better now, Gregory? 🙂