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Donald Prothero: In evolution, stasis was general, gradualism rare, and that’s the consensus 40 years on

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Quite late in his career, evolutionary biologist Donald Prothero (Occidental College) says some very interesting things about Stephen Jay Gould’s largely abandoned challenge to Darwinism:

The “punctuated equilibrium” paper is a masterpiece of writing and incisive thinking, which poses a number of interesting issues. The first part is a general discourse on the philosophy of science, which argues that all scientists are products of their time and culture and tend to see what they expect to see. In this context, Darwin led paleontologists to expect phyletic gradualism, which they vainly tried to document for over a century before the allopatric speciation model came along.

It’s not clear that abundant evidence followed the model – more like a few aha! moments in the general bleakness.

For the first decade after the paper was published, it was the most controversial and hotly argued idea in all of paleontology. Soon the great debate among paleontologists boiled down to just a few central points, which Gould and Eldredge (1977) nicely summarized on the fifth anniversary of the paper’s release. The first major discovery was that stasis was much more prevalent in the fossil record than had been previously supposed. Many paleontologists came forward and pointed out that the geological literature was one vast monument to stasis, with relatively few cases where anyone had observed gradual evolution. If species didn’t appear suddenly in the fossil record and remain relatively unchanged, then biostratigraphy would never work—and yet almost two centuries of successful biostratigraphic correlations was evidence of just this kind of pattern. As Gould put it, it was the “dirty little secret” hidden in the paleontological closet. Most paleontologists were trained to focus on gradual evolution as the only pattern of interest, and ignored stasis as “not evolutionary change” and therefore uninteresting, to be overlooked or minimized. Once Eldredge and Gould had pointed out that stasis was equally important (“stasis is data” in Gould’s words), paleontologists all over the world saw that stasis was the general pattern, and that gradualism was rare—and that is still the consensus 40 years later. – “Darwin’s Legacy,”eSkeptic , February 15, 2012 (scroll down)

If stasis is the general pattern, why do we hear so little about it?

For that matter, if “stasis was the general pattern, and that gradualism was rare—and that is still the consensus 40 years later” why does the Darwin lobby oppose allowing students to learn about stasis?

Better still, reflecting on some of his own work, Prothero tells us,

In four of the biggest climatic-vegetational events of the last 50 million years, the mammals and birds show no noticeable change in response to changing climates. No matter how many presentations I give where I show these data, no one (including myself) has a good explanation yet for such widespread stasis despite the obvious selective pressures of changing climate. Rather than answers, we have more questions—and that’s a good thing! Science advances when we discover what we don’t know, or we discover that simple answers we’d been following for years no longer work.

Is that really how science advances? Good to know. To judge from typical evolutionary biologists of Prothero’s vintage, their form of science supposedly advanced by closing ranks and spouting Darwinian gradualism at the public – even though they knew it wasn’t true.

And then wittering to the world that people didn’t believe them, when they didn’t even believe themselves.

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David B. Gibson, You write: You also seem to be assuming that each mutation must run all the way to complete fixation before the next one can begin. But if you are average, you have about 200 genetic differences from your father. So in a fairly large interbreeding population (a species) there are surely many thousands of mutations each a potential candidate for fixation, at any given time. The bulk of what NS does is to eliminate deleterious mutations. Hence, we have "conserved" regions of the genome. So, for a specific change to take place effecting a positive change, the change just can't occur anyplace along the length of the genome, but instead, must take place at a very specific site. To get a mutation at a very specific site takes a long time in a small population. In the calculation I made, I simply ignored fixation time altogether, since what was predominating the entire process was the time for the mutation itself to arise. If most mutations are harmful or neutral, then having 200 per generation of them only means they're irrelevant or dangerous. For fixation to occur, it is NOT enough for the mutation simply to occur one time in one individual. The same mutation must happen 2N times at the very same locus somewhere in the population, before fixation will take place. This is because the needed mutation is far more likely to die out along the way, than to find its way to fixation. So, I think you assume a way too rosy scenario. The whole point Prothero makes is that despite incredible changes in environment---in which positive selection should have a field-day---stasis is the rule. This does not support your rosy scenario as far as I can see. PaV
tjguy Yes origin subjects are not or very little open to the scientific method. This was what YEC leader Henry Morris always said. I don't agree in the millions of years thing as I'm yEC. Yet your criticisms and evolutionists assertions are based on fossils being rightly place in time and space by geology. Does not this mean you are trying to falsify a biological conclusion by a non biological point? Is it not a shadow flaw of logic from the beginning to prove evolutionary biology by geology and not actual biological investigation? ID folks bump into this too. Can one do biology on a rock? Scientific biological research!? Robert Byers
corrected link:
Mandy Moore - Only Hope http://www.youtube.com/watch?v=NpExJQuzpqk
David W. Gibson you state:
But if you are average, you have about 200 genetic differences from your father. So in a fairly large interbreeding population (a species) there are surely many thousands of mutations each a potential candidate for fixation, at any given time.
yet these 'about 200 genetic differences' you innocently alluded to are actually about 100 to 60 deleterious mutations: Notes to that effect:
Genetic Entropy - Dr. John Sanford - Evolution vs. Reality - video (Notes in description as to the overwhelming detrimental mutation rate) http://vimeo.com/35088933
This following study confirmed the detrimental mutation rate for humans, of 100 to 300 per generation, estimated by John Sanford in his book 'Genetic Entropy' in 2005:
Human mutation rate revealed: August 2009 Every time human DNA is passed from one generation to the next it accumulates 100–200 new mutations, according to a DNA-sequencing analysis of the Y chromosome. http://www.nature.com/news/2009/090827/full/news.2009.864.html
Yet this more recent study found a slightly lower figure than Dr. Sanford's estimate:
We Are All Mutants: First Direct Whole-Genome Measure of Human Mutation Predicts 60 New Mutations in Each of Us - June 2011 Excerpt: Equally remarkably, the number of mutations passed on from a parent to a child varied between parents by as much as tenfold. http://www.sciencedaily.com/releases/2011/06/110613012758.htm
But more importantly, this 'slightly detrimental' mutation rate of 100 to 200, or even 60, per generation is far greater than what even evolutionists agree is an acceptable mutation rate since detrimental mutations will accumulate far faster that what 'selection' can eliminate them from any given genome:
Beyond A 'Speed Limit' On Mutations, Species Risk Extinction Excerpt: Shakhnovich's group found that for most organisms, including viruses and bacteria, an organism's rate of genome mutation must stay below 6 mutations per genome per generation to prevent the accumulation of too many potentially lethal changes in genetic material. http://www.sciencedaily.com/releases/2007/10/071001172753.htm
Moreover, you desperately appealed to 'inbreeding', of all things, as a solution to the fixation of mutations PaV pointed out, yet contrary to your desperate appeal, the evidence itself, from inbreeding studies, actually confirms the exact opposite conclusion from neo-Darwinism. i.e. Inbreeding actually is a strong confirming evidence for Genetic Entropy as the real principle governing biology; i.e. The slow accumulation of 'slightly detrimental mutations' in humans, that is 'slightly detrimental mutations' which are far below the power of natural selection to remove from our genomes, is revealed by these following facts:
“When first cousins marry, their children have a reduction of life expectancy of nearly 10 years. Why is this? It is because inbreeding exposes the genetic mistakes within the genome (slightly detrimental recessive mutations) that have not yet had time to “come to the surface”. Inbreeding is like a sneak preview, or foreshadowing, of where we are going to be genetically as a whole as a species in the future. The reduced life expectancy of inbred children reflects the overall aging of the genome that has accumulated thus far, and reveals the hidden reservoir of genetic damage that have been accumulating in our genomes." Sanford; Genetic Entropy; page 147 Children of incest - Journal of Pediatrics Abstract: Twenty-nine children of brother-sister or father-daughter matings were studied. Twenty-one were ascertained because of the history of incest, eight because of signs or symptoms in the child. In the first group of 21 children, 12 had abnormalities, which were severe in nine (43%). In one of these the disorder was autosomal recessive. All eight of the group referred with signs or symptoms had abnormalities, three from recessive disorders. The high empiric risk for severe problems in the children of such close consanguineous matings should be borne in mind, as most of these infants are relinquished for adoption. http://www.jpeds.com/article/S0022-3476%2882%2980347-8/abstract
Inbreeding is also a very big problem that must be guarded against in animal husbandry. Thus David, in you trying to avoid PaV's observation, you have in fact run into another brick wall of empirical evidence which testifies directly against what you had wished for, and imagined, to be true. i.e. you have no evidence for your proposition but only wishful, misguided, speculation! Verse and Music:
Romans 8:20-21 For the creation was subjected to frustration, not by its own choice, but by the will of the one who subjected it, in hope that the creation itself will be liberated from its bondage to decay and brought into the glorious freedom of the children of God. Mandy Moore - Only Hope http://www.youtube.com/v/0ofeDruIwTM&fs=1&source=uds&autoplay=1
aV, I agree directional changes imply directional selection. Usually this is a changing environment - slow changes in temperature, altitude, humidity, etc. There is of course plenty of NON-directional speciation. Your calculation (if I'm reading you right) assumes that inter-generational morphological (fossil-visible) changes are always tiny, which is not always true. You also seem to be assuming that each mutation must run all the way to complete fixation before the next one can begin. But if you are average, you have about 200 genetic differences from your father. So in a fairly large interbreeding population (a species) there are surely many thousands of mutations each a potential candidate for fixation, at any given time. So my speculation was that IF most changes are small or invisible at the fossil level (for example, different pheromones, mating rituals, etc. causing breeding isolation), and IF most speciation is not directional, at the paleontological level what you see is stasis. Since not all changes are non-directional or morphologically tiny, those represent the punctuation. David W. Gibson
David B. Gibson:
It takes a few speciations, and those must be directional, before experts can distinguish species in the lab. It takes a LOT of such directional changes before paleontologists can see changes in the fossils.
Directional changes implies positive/directional selection. This involves fixation. Fixation involves fixation times and time for mutations to arise. Assuming s=0.1, N= 10^3, and a mutation rate of 10^-7, and using a fixation time of 2Ns generations, for a SNP, I get a figure of roughly 1 million years. So, in a geological span of 10 million years, we could count on 10 SNPs, or less. How could so few SNPs change one species to be noticeably different from another? PaV
More bad news:
After six years of work and publication, the conclusion is clear: none of the common Ice Age mammals and birds responded to any of the climate changes at La Brea in the last 35,000 years, even though the region went from dry chaparral to snowy piñon-juniper forests during the peak glacial 20,000 years ago, and then back to the modern chaparral again.
When arguing with neutralists like Elizabeth Liddle, the presumption always was that in a changed environment, neutral alleles would be selected, and speciation would occur. But it doesn't happen. Without the imagination at work, Darwinism would never be found to exist. PaV
From Prothero:
When I finally plunged in and plotted and analyzed my data carefully, it was clear that nearly every lineage showed stasis, with one minor example of gradual size reduction in the little oreodont Miniochoerus. I could point to this data set and make the case for the prevalence of stasis without any criticism of bias in my sampling. More importantly, the fossil mammals showed no sign of responding to the biggest climate change of the past 50 million years (the Eocene-Oligocene transition, when glaciers appeared in Antarctica after 200 million years). In North America, dense forests gave way to open scrublands, crocodiles and pond turtles were replaced by land tortoises, and the snails changed from those typical of Nicaragua to those of Baja California. Yet out of all the 160 lineages of mammals in this time interval, there was virtually no response. To paraphrase Rhett Butler, “Frankly, my dear, the mammals don’t give a damn.”
This isn't good for Darwinism. Another day; another bad day for Darwinism. PaV
David W. Gibson, despite the extremely biased contortions you would wish to visit upon the fossil record, the plain 'elephant in the living room' fact is that the fossils are consistently characterized by sudden appearance of a group/kind in the fossil record, then rapid diversity within the group/kind, and then long term stability (and even deterioration of variety within the overall group/kind, and even within the specific species of the kind, over long periods of time). Of the few dozen or so fossils claimed as transitional, not one is uncontested as a true example of transition between major animal forms out of millions of collected fossils.,,, David, as much as may wish and imagine to the contrary, you simply do not have the actual real world evidence that you need to make your case for Darwinian gradualism. Moreover, as pointed out previously, soft-bodied fossils are found alongside hard-bodied fossils in the pre-Cambrian strata thus you simply cannot appeal to imperfections of the fossil record as a excuse for why we don't see transitional fossils between the major groupings of life:
At North Dakota State University, Presenting the Positive Case for Design - Casey Luskin - February 14, 2012 Excerpt: Indeed, Simon Conway Morris notes in his book Crucible of Creation that in the Burgess Shale fossil collections which document the Cambrian explosion, "about 95 per cent are either soft-bodied or have thin skeletons." [p. 140]. http://www.evolutionnews.org/2012/02/at_north_dakota056351.html
David, but the fossil record is far from the only thing that runs completely contrary to Darwinian thought, you also have insurmountable problems with overwhelming detrimental mutation rates, discordant genetic sequences between somewhat similar species, similar genetic sequences between vastly different species, layers upon layers of overlapping complexity in the genome that is completely antithetical to being explained by single mutations that gradually build that overlapping complexity from the 'bottom up', no examples of novel proteins or genes arising from any mutation-selection scenario, much less are there any examples of molecular machines being had by that scenario. The finding of Quantum Information, on a massive scale, in life, etc.. etc.. etc.. David, since it is extremely clear that Darwinism is severely lacking in any solid empirical support (Indeed neo-Darwinism is falsified by advances in quantum mechanics), why exactly do you personally feel the need to go to such great lengths to imagine excuses for it? What exactly is the payoff for you? Did Charles Darwin include you in his will or something? It is ONLY a hypothesis David!!!, and not even a very good one at that, thus why do people who should know better, and you in particular, refuse to look the evidence squarely in the eye and go on from there, instead of forcing what you would wish and imagine to be true onto the evidence? It simply makes no sense from a scientific point of view! Music and verse:
4-Him - Can't Get Past The Evidence http://www.youtube.com/watch?v=WiRQxEOWdDw John 3:19 This is why people are condemned: The light came into the world. Yet, people loved the dark rather than the light because their actions were evil.
But the good news is:
John 3:16 - Aired during the Broncos/Patriots Playoff Game - video http://www.youtube.com/watch?v=KsBGk_Ps2cQ
"it's more like history and likewise less scientific" So true. No where near as precise as the science that sends astronauts to space, etc. Gould is to be commended for having the courage to speak out against the prevailing dogma of his time. I don't think his ideas are any better though. David Gibson says that small changes in an organism would be indecipherable to paleontologists so this stasis is really what we would expect. I think he is right about the inability to discern small changes in closely related fossils, but we're not talking about just one, two, or even a hundred generations. We're talking about millions and millions of years and probably millions and millions of generations! This is truly incredible and I think it falsifies Darwinism. I mean, here is an actual prediction of Darwinism that we can actually test and it fails the test. It is like Darwinism is truly unfalsifiable. David. Continues: It is clear that evolutionary change is happening somewhere. Clearly there is much more involved than stasis. Not everyone is convinced of this, myself included, unless you are only referring to micro-evolutionary changes. Again the fossil record shows mostly stasis. Plus you yourself admitted that fossils are hard to accurately analyze which makes it easy to read evolution into the fossil record. Besides, it is the only interpretation of the fossil record which "science" allows so it has to be true. Evolution is forced on the fossils. It has to be as there is no other game in town. tjguy
Saying Scientists are a product of their time and expect to see what they expect is hogwash! Science claims to include or be the result of dispassionate methodology that is to weed out error. ITS SCIENCE they cry. Then they say those guys are biased or stupid. In reality origin issues are not open to the scientific method and so each graduating class can change its own books it read. Evolution has never had biological investigation with the scientific method applied to it. Its just accept because these evolutionists are a product of wanting to accept it and fail to see they don;'t do biological investigation. tHey do something else. This Gould guy just noticed the obvious and was more open about dirty secrets! PE is useful only because it allows creationists to point at incompetence and say science is not involved in origin subjects of past and gone events and processes. Its more like history and likewise less scientific. Robert Byers
Eric: AAARGH! Wrote a long reply, and I DID fill in the CAPTCHA, and I STILL lost all my work. So I'm using a text editor from now on. Anyway, I do not think we are really disagreeing here. I agree with Gould that what paleontologists see is stasis, which I agree is real. Species generally do NOT adapt to changing environments. They either survive them unchanged, or die off. Adaptation at that level occurs by speciation, and NOT by gradual adaptation by adopted beneficial mutations within a species. Species seem to "mature" as Gould says, and defend their genetic identities pretty aggressively. And I agree with Gould that the picture of an entire interbreeding population gradually fixing one beneficial mutation after another, and thus tracking the environment, is simply not what happens. If Darwin thought that's what happens, Darwin was wrong. I also agree with Gould that speciation itself occurs relatively rapidly and relatively locally. AND that the child species is generally so similar to the parent species that even today's experts can't distinguish them, even on dissection. It takes a few speciations, and those must be directional, before experts can distinguish species in the lab. It takes a LOT of such directional changes before paleontologists can see changes in the fossils. But clearly, evolutionary change is happening somewhere, clearly there is much more involved than stasis. And I think it's also clear that tracking directional evolutionary change visible at the fossil level requires some pretty extensive sampling - which I understand is actually happening as more and more fossils are collected and collated. So my argument is based on the question: IF evolution happens by speciation, and IF new species are at best barely distinguishable from their parents, and IF fossilization is rare and fossil data is limited (and all of these conditions seem well supported), what WOULD we see? And when I run this model, out comes punctuated equilibrium. David W. Gibson
"Punctuated equilibrium is exactly what one would expect given how fossilization works and how speciation works." Sorry, but I've got to stick with Gould on this one. The old, blame the fossil record canard isn't going to cut it. That is precisely Gould's point: statis is data. It is real. Let's not keep pounding the worn out drums of poor fossil record, and soft bodies, and 'this is what we expected all along' nonsense. The fossil record is clearly *not* what Darwinism predicted nor what paleontologists had understood to be how evolution works, which is why Gould's paper caused such a kerfluffle. That is as to Gould's data. Gould's theory, however, is a different matter. The thing that is funny about punctuated equilibrium as a theory for evolution is that it is based on the *lack* of evidence for evolutionary change -- the evolutionary change always seems to be happening just where and when we can't see it. Then we get folks proclaiming: "Of course we don't have evidence, that is just what our theory predicts." Pretty convenient. ---------- Bummer on the comments -- I know how you feel. As someone who has also lost more than one post (I know, I know, I should copy, paste, etc.), I agree that the math captcha can be easy to forget. The page should not redirect to a new page, but should stay on the same page, with all one's carefuly-thought-out comments, and let one fill out the math instead of losing everything. Eric Anderson
and yet:
Macroscopic life in the Palaeoproterozoic - July 2010 Excerpt: The Ediacaran fauna shows that soft-bodied animals were preserved in the Precambrian, even in coarse sandstone beds, suggesting that (the hypothetical transitional) fossils are not found because they were not there. http://www.arn.org/blogs/index.php/literature/2010/07/02/macroscopic_life_in_the_palaeoproterozoi Response to John Wise - October 2010 "So, where then are those ancestors? Fossil preservation conditions were adequate to preserve animals such as jellyfish, corals, and sponges, as well as the Ediacaran fauna. It does not appear that scarcity is a fault of the fossil record." Sean Carroll developmental biologist http://www.evolutionnews.org/2010/10/response_to_john_wise038811.html "Are Pre-Cambrian Fossils the Solution to Darwin's Dilemma?" - podcast - January 2012 http://intelligentdesign.podomatic.com/entry/2012-01-20T15_45_26-08_00
go figure!
Materialistic Basis of the Cambrian Explosion is Elusive: BioEssays Vol. 31 (7):736 - 747 - July 2009 Excerpt: "going from an essentially static system billions of years in existence to the one we find today, a dynamic and awesomely complex system whose origin seems to defy explanation. Part of the intrigue with the Cambrian explosion is that numerous animal phyla with very distinct body plans arrive on the scene in a geological blink of the eye, with little or no warning of what is to come in rocks that predate this interval of time." ---"Thus, elucidating the materialistic basis of the Cambrian explosion has become more elusive, not less, the more we know about the event itself, and cannot be explained away by coupling extinction of intermediates with long stretches of geologic time, despite the contrary claims of some modern neo-Darwinists." http://www.evolutionnews.org/2009/06/bioessays_article_admits_mater.html Deepening Darwin's Dilemma - Jonathan Wells - Sept. 2009 Excerpt: "The truth is that (finding) “exceptionally preserved microbes” from the late Precambrian actually deepen Darwin’s dilemma, because they suggest that if there had been ancestors to the Cambrian phyla they would have been preserved." http://www.discovery.org/a/12471 Deepening Darwin's Dilemma - Jonathan Wells - The Cambrian Explosion - video http://www.metacafe.com/watch/4154263
I wrote an extremely long, detailed reply to this post. Took me about two hours to write it. When I submitted it, I was nagged for the CAPTCHA. Great, I'll fill that in - but my long detailed reply was no longer recoverable. This is a serious bug, for anyone who makes the effort to reply usefully. I'm not about to try to write it all again. So suffice it to say, this OP fails to understand the nature of speciation, the nature of what a species IS, the limitations of the fossil record both in terms of how rare it is and how little is retained, and the nature of "stasis" given the limitations of paleontology. Stasis at the paleontological level is seething individual change at the genetic level. It's silly to say either level is "wrong". Punctuated equilibrium is exactly what one would expect given how fossilization works and how speciation works. From a genetic, population dynamics standpoint speciation is a very gradualistic process - even experts often can't distinguish a child species from its parent species. When there is long-term DIRECTIONAL change, meaning each infinitesimally-different species is different in the same way (growing larger, for example), and you get to see ONE individual fossil per N speciations, then what you see is a "punctuation". I don't think any of this is a secret, or that anyone is trying to trick anyone. But take a dozen different species of salamanders, cichlids, or seagulls. Fossilize one individual of each species. Could paleontologists distinguish them based on fossils alone? Uh, no, they'd see "stasis". Now, it seems likely that Darwin's vision of gradualism didn't quite include the role that rampant speciation plays. Not surprising - Darwin didn't have the data. Today we do. It makes sense. David W. Gibson
Here are some more quotes by leading paleontologists on the true state of the fossil record: https://docs.google.com/document/d/15dxL40Ff6kI2o6hs8SAbfNiGj1hEOE1QHhf1hQmT2Yg/edit bornagain77

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