I was searching the early edition of PNAS for the abstract of yet another sloppy “science by press release” that didn’t bother to give the the title of the paper or the DOI, and came across this paper, so it wasn’t a wasted effort.
Steve McIntyre recently mentioned:
Mann rose to prominence by supposedly being able to detect “faint” signals using “advanced” statistical methods. Lewandowsky has taken this to a new level: using lew-statistics, lew-scientists can deduce properties of population with no members.
Josh (N=0) humor aside, this new paper makes me wonder how many climate science findings would fail evidence thresholds under this new proposed standard?
Revised standards for statistical evidence
Valen E. Johnson
Significance
The lack of reproducibility of scientific research undermines public confidence in science and leads to the misuse of resources when researchers attempt to replicate and extend fallacious research findings. Using recent developments in Bayesian hypothesis testing, a root cause of nonreproducibility is traced to the conduct of significance tests at inappropriately high levels of significance. Modifications of common standards of evidence are proposed to reduce the rate of nonreproducibility of scientific research by a factor of 5 or greater.
Abstract
Recent advances in Bayesian hypothesis testing have led to the development of uniformly most powerful Bayesian tests, which represent an objective, default class of Bayesian hypothesis tests that have the same rejection regions as classical significance tests. Based on the correspondence between these two classes of tests, it is possible to equate the size of classical hypothesis tests with evidence thresholds in Bayesian tests, and to equate P values with Bayes factors. An examination of these connections suggest that recent concerns over the lack of reproducibility of scientific studies can be attributed largely to the conduct of significance tests at unjustifiably high levels of significance. To correct this problem, evidence thresholds required for the declaration of a significant finding should be increased to 25–50:1, and to 100–200:1 for the declaration of a highly significant finding. In terms of classical hypothesis tests, these evidence standards mandate the conduct of tests at the 0.005 or 0.001 level of significance.
From the discussion:
The correspondence between P values and Bayes factors based on UMPBTs suggest that commonly used thresholds for statistical significance represent only moderate evidence against null hypotheses. Although it is difficult to assess the proportion of all tested null hypotheses that are actually true, if one assumes that this proportion is approximately one-half, then these results suggest that between 17% and 25% of marginally significant scientific findings are false. This range of false positives is consistent with nonreproducibility rates reported by others (e.g., ref.5). If the proportion of true null hypotheses is greater than one-half, then the proportion of false positives reported in the scientific literature, and thus the proportion of scientific studies that would fail to replicate, is even higher.
In addition, this estimate of the nonreproducibility rate of scientific findings is based on the use of UMPBTs to establish the rejection regions of Bayesian tests. In general, the use of other default Bayesian methods to model effect sizes results in even higher assignments of posterior probability to rejected null hypotheses, and thus to even higher estimates of false-positive rates.
This phenomenon is discussed further in SI Text, where Bayes factors obtained using several other default Bayesian procedures are compared with UMPBTs (seeFig. S1). These analyses suggest that the range 17–25% underestimates the actual proportion of marginally significant scientific findings that are false.
Finally, it is important to note that this high rate of nonreproducibility is not the result of scientific misconduct, publication bias, file drawer biases, or flawed statistical designs; it is simply the consequence of using evidence thresholds that do not represent sufficiently strong evidence in favor of hypothesized effects.
=================================================================
The full paper is here: http://www.pnas.org/content/early/2013/10/28/1313476110.full.pdf
The SI is here: Download Supporting Information (PDF)
For our layman readers who might be a bit behind on statistics, here is a primer on statistical significance and P-values as it relates to weight loss/nutrition, which is something that you can easily get your mind around.
Gross failure of scientifical nutritional studies is another topic McIntyre recently discussed: A Scathing Indictment of Federally-Funded Nutrition Research
So, while some dicey science findings might simply be low threshold problems, there are real human conduct problems in science too.
@milodonharlani
It is clear that this topic is interesting to many, but this is Anthony’s blog. Without a specific OK from him, or the Mods, I am unwilling to go further with this discussion. It is very OT.
Arguably it is OT, although discussion of what is science & isn’t could IMO be considered relevant. Comparison of ID with the only slightly more scientific CACA could be instructive.
Thank you for sharing that Zeke. That was beautiful.
*************************************************
Dear Mr. Harlani,
When our host invites us to discuss Intelligent Design theory at length, I will do my best to answer any questions you have. Until then, know that you are being prayed for earnestly by someone (perhaps, by more than one of us) who cares about you. And, do bear in mind that you may be confusing the evidence for design with its implications.
Sadly, but with hope,
Janice
@ur momisugly milodonharlani
More than happy to discuss what science is and isn’t, but again it’s not about the head post topic. I have been meaning to finish an essay on science and submitting it to Anthony but haven’t managed to get a round twit. I have, however, managed to affix automatic vent openers to the vents in my greenhouse. Now I don’t have to race in and out of the house on showery, partially clouded days. I am calling this the enhanced greenhouse effect. And that’s OT for this thread, too 🙂
The Pompous Git says:
November 13, 2013 at 1:36 pm
Not sure that an EGHGE would be off topic for any thread on WUWT, but you’re right, a new topic would be better. Good on ya, mayte!
Janice Moore says:
November 13, 2013 at 1:30 pm
Prayers are always welcome. I pray daily myself.
Since our host was allowing comments on ID, I don’t see why you keep refusing to state what evidence persuades of the scientific validity of ID but not of evolution. On a blog it’s customary to make your case in your own words, using supporting quotations or links in order to bolster it. The fact is there is no evidence whatsoever in favor of ID. Its humiliated proponents were laughed out of the US District Court for the Middle District of Pennsylvania. But I would have liked to read what you yourself personally, based upon your research & study, might consider such evidence.
Thanks.
OK, I can’t resist! The “non-existent” laws of neoDarwinism:
Life is cellular
All living organisms possess genes
All life processes occur through biochemistry
Mendel’s First Law: “The Law of Segregation states that every individual possesses a pair of alleles (assuming diploidy) for any particular trait and that each parent passes a randomly selected copy (allele) of only one of these to its offspring.”
Mendel’s Second Law: “The Law of Independent Assortment, also known as “Inheritance Law”, states that separate genes for separate traits are passed independently of one another from parents to offspring.”
Re Intelligent Design, I can do no better than quote physicist Paul Davies:
milodonharlani says:
November 13, 2013 at 12:12 pm
“It’s a common mistake for non-biologists to confuse abiogenesis, the origin of life, with evolution.”
Maybe for you “evolution” means ONLY Neo-Darwinian evolution. For me it means any process that combines mutation/variation with selection, as I’m a computer scientist. No need to argue; just a clarification.
Without a pre-cellular evolution the complexity needed for the first cell absolutely kills you; and ID becomes a necessity. Simple combinatorics without a selection + mutation process (a.k.a. evolution, a.k.a. information processing) does not work on the timescale available.
See Kurzweil’s Law Of Accelerating Returns.
milodonharlani says:
November 13, 2013 at 12:01 pm
“Intelligent Design, like CACA, is not just unscientific, but anti-scientific, & for the same reason.”
CACA as you call it has been created by the UN together with all the Green NGO’s; so I guess it’s not the same reason.
“ID advocates look at flagella in bacteria & are happy to throw up their hands & give up, saying, “These structures are irreducibly complex, so couldn’t have evolved, therefore a Designer made them.””
It doesn’t help your case to overgeneralize; in fact I have not the slightest problem with macro-evolution. I also have no problem with an interfering God, as that is not a contradiction at all.
Well, it’s getting late here in EU territory; it was fun to talk to you. Good night and take care.
milodonharlani says:
November 13, 2013 at 2:11 pm (replying to)
Janice Moore ( Gail Combs search reference here.)
November 13, 2013 at 1:30 pm
I would politely challenge you, then, to find any “error” or out-of-sequence event that differs between your version of the Big Bang and evolution and what is in our original documents and the oral stories that preceded those documents. That is, matter condensing from light from the initial energy that began expanding like a wind into “nothing”. Then, that newly cooled matter grouping into the stars and cosmos and – at the same time – being separated by gravity into what is now our planet with its atmosphere and (one single large) ocean and one single original continental mass.
After that (single) ocean was formed on our planet, plants were the first life, but the atmosphere remained cloudy until these first plants released oxygen and locked up the CO2 and free iron into terrestrial beds. (The stars and moon could become visible only after life cleared the atmosphere.) But, once life began in the sea, it quickly spread spread to the land and changed into what we call dinosaurs (well certainly the predecessors of birds), then mammals (and the domesticated animals), then what we now call snakes, then (finally) man.
Please notice that the word “created” only appears once in our original documents, and those tales were told by a culture that not only did NOT have convenient Indo-Arabic numerals, but also did NOT have a zero, a decimal place, or convenient powers-of-ten notation. (Please, write 14 billion in Roman numerals.) Still, it is remarkable that these itinerant shepherds wandering between the numerous seas and oceans of our own era got all of the geology, plate tectonics, evolution, biology, chemistry, astronomy, and nuclear physics of today’s science correct. But I will claim no “Divine Inspiration” was involved in Genesis. It is, after all, up to you to find an earlier reference to any of these “recent discoveries” in the literature. 8<)
By the way, please, in any edition of any book or court case discussing your so-called ridicule of ID, replace "evolution" or Nature" or "natural selection" with "a designer" …. You will find that there is no difference.
Actually I thought it would be interesting to see if the cosmological model accepted by mainstream science – that is, the Big Bang and the Planetary Nebula Hypothesis – might be a good match for the old Roman paraphrases of diverse pre-classical pagan creation stories written in (some say bad) meter by Ovid. That would make an interesting comparison!
RACook, If there is a similarity between Genesis and the Big Bang and its subsequent epochs, this might be because the originator of this theory was a Catholic Priest. But you are welcome to it. 🙂 😀
I am not a Catholic myself, but as I understand, Big Bang and so on are officially recognized as truth by the Catholic Church.
RACook, There is one problem with interpreting Genesis in that way. The plants were created on the third day, before the sun and moon were made. Was there some long period when plant life flourished and yet there was no sun? Another source of light is implied because the light is given on the first day, and separated from darkness. The sun, moon, and stars are given on the fourth day. Also, the Hebrew word for create (bara) (as opposed to made, asa) is used twice, not once. He made man “in His image, male and female He created them.” That is the primary teaching of the Scriptures that is totally irreconcilable with Darwinism. We are, according to the “itinerate wandering shepherds,” eternal beings, spiritually unique from the animal world, having rationality and liberty, and living forever, like the angels. I suppose this belief has been found most inconvenient by various Empires and Governments. Various totalitarian States, historically, have diagnosed Christians with a mental disorder.
The area under the curve in the tail of the Gaussian distribution shown in the figure is not a p-value. William M. Briggs, Statistician to the Stars, does an excellent job of debunking p-values. I strongly suggest everyone here check out his web site: http://wmbriggs.com/blog/.
Zeke says:
November 13, 2013 at 4:20 pm
Thank you for the compliment, and the correction. Indeed, it may be critical, even vital (in its original Latin version of “life”!) that “creation” DID happen only twice – the second time being when the “soul” was created. After all, everything (we are taught) was already created a long time prior to a man’s (and woman’s) “soul” (mind, intellect, thought process, inventiveness, etc came into their being…
There is one problem with interpreting Genesis in that way. The plants were created on the third day, before the sun and moon were made. Was there some long period when plant life flourished and yet there was no sun? Another source of light is implied because the light is given on the first day, and separated from darkness. The sun, moon, and stars are given on the fourth day.
You are correct in a first level reading (or interpretation) of that text. But think a bit. We are told that the stars and sun and moon were already gathered together “above” when the earth was formed “below”; and “the waters above” certainly is a valid description of the dust, plasma, ions, fluids, and gases above the atmosphere. It’s just that “waters” one time refers to liquid fluids, and the other time refers to all fluids and gases everywhere in the cosmos.
But, the original earth’s atmosphere was opaque – like Venus, Jupiter, Saturn, Neptune, and Uranus. Nothing could be seen above it. Little light could get through, certainly not enough for life as we know it. (And, Hansen is correct: Venus is lethally too hot for life. ) But, after the plants broke that CO2 and SO2 and xxx and yyy and zzz into today’s benign oxygen and nitrogen mix, light could get through. (Note though that the oxygen we require for life was deadly to everything else that required an oxygen-free atmosphere.
Most importantly, light can get through the new atmosphere both ways: We can “see” the stars and plants and moon for the first time, and they were “set” in their places to aid in navigation and travel. And wonder. All science began really with astronomy. In every civilization. Everywhere. Without the stars to inspire wonderment, would anything past fire (and that also not possible without oxygen!) have ever been discovered?
So, “No” the two are not incompatible: The stars and moon were already formed and present and yielding light as they do now. It’s jusut that they were not visible from the earth. Yet. Note too that the collision that formed the moon had to happen BEFORE life started: certainly nothing could have survived that heat shock and impact melting all else.
The Pompous Git says:
November 13, 2013 at 2:30 pm
The refs sent me to the penalty box for several hours, so will keep my replies brief.
How exactly do those “laws” constitute “Neo-Darwinism”? By “Neo-Darwinism” do you mean the Modern Synthesis, which isn’t so modern any more? What makes the observations that life is cellular & biochemical laws & part of Neo-Darwinism, rather than just biology in general, for instance? As I’m sure you’re aware, “law” in science is less clearly defined than “hypothesis” or even “theory”.
The Pompous Git says:
November 13, 2013 at 2:34 pm
You are confusing the hypothesis of a designed universe, to which I’ve alluded as still a defensible metaphysical position, with the doctrine of “Intelligent Design”, which is specifically about biological structures & processes. It was invented to get around court rulings against teaching creationism in public schools & despite losing in federal court is still pushed by groups such as the Discovery Institute.
DirkH says:
November 13, 2013 at 2:39 pm
As I’ve commented here before, the term “evolution” in biology means both the observed fact of evolution & the body of theory explaining how it works. Maybe I should repeat that in every comment on evolution.
“Without a pre-cellular evolution the complexity needed for the first cell absolutely kills you; and ID becomes a necessity. Simple combinatorics without a selection + mutation process (a.k.a. evolution, a.k.a. information processing) does not work on the timescale available.”
Your error in assuming that combinatorial math controls abiogenesis is a common one. Kurzweil’s Law Of Accelerating Returns doesn’t apply.
Neither I nor abiogenesis researchers “need” intelligent design to explain the development of life from its precursor chemicals. Nothing could be farther from the truth. There is no reason whatsoever to posit such a supernatural, anti-scientific fantasy.
Instead of making a baseless assertion, how about actually studying what is known & not known about the prebiotic processes that led to the first living things?
What do you suppose the timescale available to be? If life arose from its precursors on earth, there were at the very least 700 million years before the first hint of life in the geological record. If life arose extraterrestrially, then on the order of ten billion years is available.
Many of the ingredients of life as we know it self-assemble, like some peptides, PAHs & the lipids that form cell membranes. Precursor compounds existed on the early earth in great abundance. They didn’t even need to be made here, although they could have been from simpler compounds, but arrived on space rocks, just as they still do. The number of complex organic chemicals in meteorites is astonishing.
http://en.wikipedia.org/wiki/Murchison_meteorite
Naturally occurring chemicals helped catalyze the synthesis of the first biologicals, ie RNA strands capable of replication. For instance, polycyclic aromatic hydrocarbons (PAHs) are common in the interstellar medium, comets & meteorites.
http://amesteam.arc.nasa.gov/Research/cosmic.html
In a self-ordered PAH stack, the separation between adjacent rings is 0.34 nm. Remarkably, this is the same separation found between adjacent nucleotides of RNA & DNA. Smaller molecules attach themselves naturally to the PAH rings. However PAH rings, while forming, will swivel around on one another, which tends to dislodge attached compounds in collisions with those above & below. Hence, preferential attachment of flat molecules is encouraged, such as pyrimidine & purine nucleobases, the key constituents (& information carriers) of RNA & DNA. These bases are similarly amphiphilic, so also tend to line up in similar stacks.
Ice has also been found to catalyze formation of RNA, which has been discovered to act both as an enzyme in protein formation & information source. Great strides have been made recently in understanding the pathways from complex organic compounds to life. Some key issue remain, but it’s just chemistry, not magic.
http://www.nature.com/nature/journal/v502/n7472/full/502412d.html
Ice is gaining support at the expense of fire, ie oceanic thermal vents as the cradle of life.
You are right however that evolution probably started working very early in the history of life, selecting fitter proto-cells & eventually leading to the differentiation in functions between RNA & DNA. for instance.
@ur momisugly milodonharlani
First, I quote Theodosius Dobzhansky: “Nothing in Biology Makes Sense Except in the Light of Evolution”. In the world I inhabit, NeoDarwinism = the Modern Synthesis = The Received View in Biology. Biology has scientific laws just as other disciplines. Most theories invoke those laws. Live with it.
It is not I who confuse Intelligent Design with creationism. There is a world outside the USA that does not accept as Gospel Truth everything that comes out of the USA. Or anywhere else for that matter. I don’t give a fiddler’s fart that creationists attempt to own a term; they don’t.
I’m currently rereading Ernst Mayr’s One Long Argument. The first sentence reads: “A modern evolutionist turns to Darwin’s work again and again.” Why does using the term “evolutionist” make me a creationist and not Mayr? I know you haven’t gone that far, but many have. And you have taken me to task for using it.
The chapter I’m reading is titled, incidentally: A Hard Look at Soft Inheritance: Neo-Darwinism. See above.
Zeke says:
November 13, 2013 at 4:20 pm
“I am not a Catholic myself, but as I understand, Big Bang and so on are officially recognized as truth by the Catholic Church.”
The Roman, Greek & Russian Orthodox Catholic Churches also recognize the scientific validity of evolution. In 1973, the great evolutionary biologist & devout Russian Orthodox Christian Theodosius Dobzhansky published in American Biology Teacher his famous essay, “Nothing in Biology Makes Sense Except in the Light of Evolution”, criticizing creationism & espousing theistic evolution. That same year I told my fundamentalist students at an originally Baptist college that they were free to inject God into the history of life on earth at any point they chose, although evolution works fine without divine intervention.
To your excellent exegesis on the creation myth in Genesis 1, I’d add that the vault or firmament of heaven in Hebrew is “raqiya` (רקיע)”, which means something pounded out (the word is onomatopoetic, like English “racket”), as in a sheet of metal, to which the firmament is compared elsewhere in the Old Testament. This solid dome of heaven separates the waters above the vault from the waters below it. This is a monotheistic reworking of the Mesopotamian creation myth, picked up by the Judean prisoners during the Babylonian Captivity.
Note further that when God does get around to creating the sun & moon, He sets them in the newly minted vault, but later in the Bible we learn that the sun rises as a bridegroom or a strong man to run a race & travels over the flat earth that forms the floor of the dome, returning afterwards to the place of his origin. And we learn further that God Himself opens & shuts the storehouses of rain, snow & other precipitation above the dome. And we learn about the water that wells from under the immovable pillars of the earth.
Then there’s the second creation story in Genesis, which begins in Chapter 2 after the snippet of the end of the first story in the chapter’s initial verses. The order of creation in the second story–man, plants, animals, & then woman from the man’s rib–differs markedly from the order in the first story–plants, sun & moon, animals, men & women together.
I will grant however that it’s a lot easier to read modern biology into the biblical accounts than it is modern astronomy, geology, meteorology or hydrology. Genesis says that the waters brought forth creatures, & that’s sort of what happened. But the land bringing forth the plants doesn’t quite make it. Green plants spread onto land from the waters, & evolved after animals, not before them.
The Pompous Git says:
November 13, 2013 at 7:24 pm
The ID that Janice Moore & I were discussing was specifically the ID movement in the US, which is about biological creationism not cosmological. It’s not about the kind of design posited by the physicist whom you quoted, but about the kind of propagandists of whom she posted video. The point isn’t that ID is American (& also popular in Muslim countries), but that it was specifically biological. So the cosmos was off an already off topic.
I couldn’t agree with Dobzhansky more, whom I quoted above. But why do I have to live with your idea of what constitutes “Neo-Darwinist” laws? Those you cited aren’t unique to “Darwinism”. That there are phenomena in biology called “laws” by some doesn’t make them necessarily Neo-Darwinistic/ian. The Modern Synthesis of the interwar years, if that’s what you meant, is now being challenged as Newtonian physics (“Newtonism”?) was by Einstein, with advances in understanding of how genomes work. Please cite what Dobzhansky, Mayr or other leading evolutionary biologists consider the “laws” of Neo-Darwinism, then we can discuss them, if allowed.
RACookPE1978 says:
November 13, 2013 at 5:18 pm
“There is one problem with interpreting Genesis in that way. The plants were created on the third day, before the sun and moon were made. Was there some long period when plant life flourished and yet there was no sun?”
No, there was not such a period. There are chemosynthetic autotrophs which don’t need sunlight, but they’re not plants.
“We are told that the stars and sun and moon were already gathered together “above” when the earth was formed “below”; and “the waters above” certainly is a valid description of the dust, plasma, ions, fluids, and gases above the atmosphere. It’s just that “waters” one time refers to liquid fluids, and the other time refers to all fluids and gases everywhere in the cosmos.”
No, this is not a valid description of anything. Waters in Genesis means liquid H2O. It doesn’t mean plasma, ions, other fluids and gases above the atmosphere.
Nor is your quotation from Genesis correct. The sun & moon in Genesis 1 were not “gathered”. That was the waters. God said “Let there be” the sun & moon, & there they were. He “set” them in the vault of heaven.
“But, the original earth’s atmosphere was opaque – like Venus, Jupiter, Saturn, Neptune, and Uranus. Nothing could be seen above it. Little light could get through, certainly not enough for life as we know it. (And, Hansen is correct: Venus is lethally too hot for life. ) But, after the plants broke that CO2 and SO2 and xxx and yyy and zzz into today’s benign oxygen and nitrogen mix, light could get through. (Note though that the oxygen we require for life was deadly to everything else that required an oxygen-free atmosphere.”
The composition of earth’s atmosphere in the Hadean Eon remains unclear, although under investigation by geologists. In science, unlike religion, evidence is required to support speculations. Some geologists believe that the earliest atmosphere included large amounts of nitrogen. Others believe that it was composed largely of carbon dioxide & water vapor, along with some other volcanic gases from steaming vents & volcanoes. Early in the Hadean, earth’s atmosphere was probably too hot to allow liquid water to condense, but inclusions in younger strata suggest sedimentary rocks formed later in the Eon, which implies existence of surface water.
The second atmosphere of the earth in the Archean Eon is better understood. It consisted largely of nitrogen plus carbon dioxide & inert gases, produced by volcanic outgassing, supplemented by gases generated during the late heavy bombardment of earth by huge asteroids. A major part of carbon dioxide emissions was soon dissolved in water & built up carbonate sediments.
Water-related sediments have been found dating from as early as 3.8 billion years ago. About 3.4 billion years ago, nitrogen was the major part of this then stable second atmosphere. Hints of early life forms have been found as early as 3.5 billion years ago, or possibly even 3.8 Ba.
A third atmosphere developed during the Great Oxygenation Event. Free oxygen did not exist in the atmosphere until about 2.4 Ba. Its appearance is indicated by the end of the banded iron formations. You’re right that the photosynthetic organisms which made this oxygen created a catastrophic crisis for other living things. But these organisms would have needed light, so the second atmosphere under which they evolved wasn’t opaque.
“So, “No” the two are not incompatible: The stars and moon were already formed and present and yielding light as they do now. It’s jusut that they were not visible from the earth. Yet. Note too that the collision that formed the moon had to happen BEFORE life started: certainly nothing could have survived that heat shock and impact melting all else.”
If by “the two” you mean creation accounts in Genesis (& other parts of the Bible) & what science has been able to infer from actual physical evidence, then yes, they are incompatible. The Bible is not a science text. As Cesare Cardinal Baronio said to Galileo, “The Bible teaches us how to go to heaven, not how the heavens go”.
@ur momisugly milodonharlani
I’m not at all sure why you would think that the laws of biology do not apply to Neo-Darwinism. It’s too silly to argue about.
The Pompous Git says:
November 13, 2013 at 9:30 pm
You’re right it’s silly to argue about this, but sillier still IMO was your listing “laws” which aren’t part of Neo-Darwinism. ie the Modern Synthesis, as the “laws of Neo-Darwinism”. The Modern Synthesis, along with the rest of biology since the early 19th century, of course assumes that life is cellular & biochemical, but those facts aren’t what distinguish it from “Paleo-Darwinism” or any other theory in biology. I would have thought that to a philosopher these distinction would be obvious.
@ur momisugly milodonharlani
Of course we can expect Kevin Kelly to know all this stuff backwards… And it’s kinda handy, I suppose, to distract as much as possible from directed evolution which was the point of Kelly’s piece 🙂 Evolution’s all really, really, really random; like over 30 distinct species of plants acquiring the same gene complex (C4) virtually simultaneously. No need to explain that stuff.
BTW how long have Mendel’s laws not been part of the Modern Synthesis? They were the last time I looked.
The Pompous Git says:
November 13, 2013 at 10:26 pm
Mendel’s ” Law of Segregation” & “Law of Independent Assortment”, as amended by population genetics, were indeed part of the Modern Synthesis. That life is cellular & biochemical aren’t, since those facts are givens for all of biology. But much has changed since the 1930s, including what “gene” means. A “Post-Modern Synthesis” is emerging.
Kevin Kelly is not a biologist, if you’re referring to whom I think you are. There is no such thing in biology as “directed evolution”, since there is no Director. There is however “directional” evolution, which is driven by good, old-fashioned selection, as opposed to stochastic processes.
Why does the evolution of the C4 pathway from the C3 in different plant lineages strike you as somehow remarkable? For starters, it wasn’t “nearly simultaneous”. Different species developed the C4 pathways at different times, which was helpful in their environments. Then, when CO2 levels dropped in the Oligocene, these plants enjoyed selective advantages over other plants (some might have developed C4 even earlier). This selective pressure got really intense in the late Miocene, when an apparent explosion of C4 abundance occurred, but that doesn’t mean that the pathway suddenly evolved then. In the Pliocene & even more during the Pleistocene glaciations, this tendency was reinforced.
http://www.cas.miamioh.edu/~meicenrd/anatomy/Ch10_Photosynthetic/IJPS_Keeley_Rundel2003.pdf
No need to posit a Director. Just good, old-fashioned darwinian natural selection. Survival of the fittest, where “fitter” means better able to conserve water & get by with less CO2 in a drier, lower CO2 environment.
To say nothing of the CAM pathway, which is ancient, but originated in the sea, perhaps oddly now that it’s prevalent in desert succulents.