Proponents of Intelligent Design have used the notion of irreducible complexity to bludgeon evolution theory by insisting that complex biological structures ranging from the human eye to the bacterial flagellum could not have evolved in stages because none of the intermediate versions would have functioned properly. They have never offered evidence for this notion of irreducible biological complexity, they simply declare it by fiat as an inescapable logical conclusion. Unfortunately for Intelligent Design, scientists are striking back and providing detailed evidence about the evolution of complex biological structures.
Intelligent Design advocates chose poorly when they selected the compound eye of vertebrates as one example of a complex biological structure that could not have evolved in stages. Even first-year biology students know about eye spots in planarians which are simple pigment patches at the front of the worm that are connected to their simple nervous system. They can only sense light versus dark, but that is enough for them to get by as planarians. There are many intermediate forms of eyes in the animal kingdom ranging from simple pits in the skin lined with receptor cells, all the way up to the compound eyes of animals with their cornea and lens arrangement. Fossils of trilobites that are over 500 million years old show they possessed eyes very similar to those of modern day insects. Our complex eyes clearly evolved from the simpler eyes in ancestral species, and the presence of the critical light-receptive pigment called “opsin” in all animals highlights this shared ancestry. The same molecule is used to sense light in worms, jellyfish, eagles and humans.
But what about the evolution of complex molecular structures, such as Intelligent Design’s perennial favorite, the bacterial flagellum? For details on how the flagellum most likely evolved stepwise from a bacterial secretory system, see:
Scientists are increasingly using genetics and molecular biology to dissect probable evolutionary steps in the formation of various molecular devices in animals, and one such recent study by Ken Kosik and colleagues has looked at cellular junctions in certain species of sponges.
Yes, sponges really are primitive animals, not just absorbent kitchen cleaning items. Sponges are among the simplest of multicellular animals, and they lack internal organs, including a nervous system. However, the mobile larval form of a species of sponge which has been studied extensively has been found to possess the majority of genes for making a critical part of neural synapses, even though the sponge larvae do not have nerve cells. Instead, they have cells called flask cells.
The flask cells of these larval sponges have many features of primitive sensory cells, including a cilia and secretory vesicles. Despite the fact that the larva have no nervous system, they nonetheless possess approximately 70% of the genes required to make the complex structure of neural synapses known as the “postsynaptic density” (PSD). PSD’s are the receptive part of a synapse which receives signals in the form of neurotransmitters released by other nerve cells. So if these sponges don’t have a nervous system, why would their larvae need so many genes associated with synapses?
The answer is that they appear to be using these genes to make signaling structures that are distantly related to neural synapses in animals. The genes in these sponges show a remarkable similarity to the related genes in animals that possess nervous systems, including the structural elements that hold the molecules into a functional array. The authors note that these proto-synaptic structures are not only likely candidates for the evolutionary stepping stones to synaptic contacts between neurons, they may represent prototypical cellular junctions in general which could have led to the development of many specialized junctions between cells found in later-evolving animals.
The take home message from such studies is that the same genes and molecules are used over and over again by different animals to perform many different functions, and that these simple building blocks can be mixed and matched in differing ways to produce increasingly complex molecular devices and organ systems. This derived complexity in no way undermines the notion of evolution, it fortifies the theory immensely. Rather than being another gap in human knowledge about evolution, molecular biology is demonstrating how very complex biological structures can evolve from simpler systems by making use of modular units that can be combined in many different ways, with each change making the system function more robustly. Eye spots are just fine for worms, but not for eagles, and yet the 530 plus million years of evolution between them provided innumerable opportunities for step by step improvements in vision.
Intelligent Design proponents don’t provide us with scientific data, they provide us with uninformed commentary and conjecture. Their arguments may work well with the uneducated public, but they are not based on scientific facts. The main underpinning of their arguments rests entirely on the concept of irreducible complexity. But Darwin is striking back with scientific data that shows how life is like a self-assembling Lego set, mixing and matching simple building blocks to make increasingly complex structures. When Darwin strikes back, he does so with great vigor and eloquence.
Dr. John Moffett is an active research neuroscientist in the Washington, DC area, who has published articles on the nervous and immune systems. Dr. Moffett is also the author and webmaster of the political opinion website www.Factinista.org, and is a Managing Editor at OpEdNews.com.
Yes, we do disagree on this, despite agreeing on political issues.
If you read the articles that I linked to (tough reading, to be sure), you will have a better appreciation of the inherited connectedness of all life on earth.
This connectedness could theoretically be due to a superior being making the proper conditions for all things as they are now. But even if that were the case, the inherited relations between all species on earth exist, showing that later-derived animals are descended from earlier species. So if some “super being” started events in motion, the same results obtain that biological organisms evolve over time into differentiated species.
No rational, educated person thinks that “6000 years ago, God made things as they are today”. Evolution is a fact, the only possible debate remaining is what started evolution on it’s course.
But that’s another discussion altogether!
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John R Moffett (71 articles, 11 quicklinks, 2 diaries, 523 comments)
on Friday, June 29, 2007 at 5:21:27 PM
Gormley, you know that I didn't say that creationists are irrational. I said that evolution is a fact. If some creationists insist that evolution is a façade, then they are living in some bygone world of the 19th century. Please read the links that I posted, and then get back to me with your objections.
Even many creationists now admit that the evidence for evolution is overwhelming. The origins of life are more speculative.
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John R Moffett (71 articles, 11 quicklinks, 2 diaries, 523 comments)
on Friday, June 29, 2007 at 5:38:44 PM
They're not scientific arguments, but more intuition. I could not have said it better myself. This is why your side does not need to be taught in school. Also you state that if I see a rolex watch I will not think about random process but will know something made it. I have seen watches being made by people. I have never seen a god or something make a planet or star. And we are created by something its called evolution. I have talked to many creationist and what I come away with is a desire to be special. I did not evole from an ape because I am a special creation of god. If your belief is true we all are creations of god and one is not better than the other.
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mike (0 articles, 0 quicklinks, 0 diaries, 86 comments)
on Friday, June 29, 2007 at 5:24:02 PM
John: In his meandering around the universe in "Thought Experiments" Einstein noted/theorized that the quantum consisted of/carried or created "Quanta." Quanta are packets of light which were considered self-contained and of a Gestalt which was irreducible.
In my Ford Foundation Fellowship year, (one of my several years of Agnosticism, while studying Anthro), done under the supervision of my mentor the great Guru of Traveling Museum exhibitions, Lothar Witteborg, then at Field Museum, we examined a number of exceptions to strict Darwinian evolution. Darwin was, for the record, especially I aim this at Fundamentalist's and Creationist's , Darwin WAS, like Einstein quite definitely, not an atheist!
DARWIN, "There is grandeur in this view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one; and that, whilst this planet has gone circling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved."
Being among other things, a cultural/physical Anthropologist and, if there is one thing I learned about "science," it is that there are NO final answers, as Omar Khay'yam, so eloquently pointed out in his Rubaiy'yat. What was the gospel for several generations, is nothing more than a, "nice-try" several later.
I studied Anthro as a guest for almost two years at Field Museum of Natural History in Chicago, with cart'e blanche by Virtue of my Fellowship to do and ask and discuss and research without restriction, and so I did and NO ONE, of the scientists, there, ever spoke of the THEORY of evolution as anything other than, The Theory of Evolution and it will, for the most part, do for me, until a cleaner explanation comes along and I have no doubt one will, one always has and always will until we know everything, which is a long way off. Did things on earth evolove, certainly looks that way, but the Theory has exceptions, notable and not "Exceptions that prove the Rule," which is another stupid idead, bytheway, exceptions do not prove the rule, they merely take into account the laws of "chance."
The "Irreducible Complexity" of the human eye is unmatched in the animal kingdom as it is currently composed and tied to the brain, and as it stands is reality. However, such "Irreducible Complexity" does NOT rule out MUTATION. Mutation can make quantum leaps at times.
I am open to whatever comes along, because to close one's mind is unscientific, but what I am fairly clear about that in the final analysis, the Creator is, and was, the Master Scientist, Physicist/Mathematician and created all by a set of Laws of Physics. Does that mean I rule out ironies, certainly not. Do I accept Creationism? I do not, it is unscientific, and makes little sense as it is outlined by those who beleive the earth is onlt 4400 years old-That idea is maddeningly, Head-in-the-sandish, and highly unintellectual, and if the Creator has shown us anything, it is that He is The Scientist.
What the scientists were saying was complicated in detail, but simple in concept.
The molecules that make up bacteria, bivalves, bison and bipeds are all related. This molecular similarity shows that all life is connected by inheritance. What got life started on its course is one issue... the details of evolution are another issue.
You can believe in a creator, and still strive to understand what exactly was created.
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John R Moffett (71 articles, 11 quicklinks, 2 diaries, 523 comments)
on Friday, June 29, 2007 at 6:43:05 PM
I get what your saying. OK... I definitely believe in the connectiveness of
all life, similar molecules,etc. Where we differ is how this process started.
I'm no expert on evoluttion (big surprise).
Here's an observation I've made. Let's look at man 2000 years ago.
Can we agree that little has changed in the physical make-up of man in
those 2000 years? Let's extrapolate and assume that if man did evolve from
lower life forms then it would take tens of thousands of years for men to
make significant changes. With this assumption wouldn't intelligent
man have to have existed at least 10 thousand years from this present time? Where are the written records of his existence? Where is the archaelogical evidence?
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Bob Gormley (0 articles, 0 quicklinks, 2 diaries, 772 comments)
on Friday, June 29, 2007 at 7:09:30 PM
Well, there is one thing going for you (actually two things).
1)- Not that I place myself in their company but Einsten, Darwin, Gödel, I and most of my Profs, all accepted the existence of a Creator.
2)- The question which led to My FFF, concerning Homo-sapiens (HS), was never answered to my satisfaction and was the springboard to my winning the FFF. In the interim between the failure of Homo-erectus, the advent of Neanderthal, and the coming of HS, there was not time for evolution or mutation of an organism of the size and complexity of man, and we do not have the DNA of Neanderthal, though there was some evidence of cohabitation of Neanderthal and HS in one or two cave burials, that was mush after the fact, and gave some evidence of sexual intercourse between HS and Neanderthal's, I doubt that there were any offspring, but if there were we have no such evidence thereof.
Finally, the line of evolution seems to have run out at Neanderthal. Hence my FFF winning question, Quo Vadis Neanderthal?, or better still, transi hinc et vade, Neanderthal? And autem cum venerit nemo scit unde sit, Homo-sapiens? (my Latin is a bit rusty, perhaps, but I think that was how I put it).
So, then, how did HS get here, whence came he? No one knows, everyone either avoids the subject, sweeps it under the rug, or shrugs palms up on that issue. I mean, we still don't know what causes certain water turbulance, in rivers.
Fortunately there are remaining at least, some mysteries. The "explanations" of the arrival or appearance of HS are about as lame as Creationism.
So, he represents the last great white hope of direct creation of one subspecies, but I very much doubt it because even Neanderthal displayed at the Cave in Shanidar-Iraq, definite belief in immortality in the burial of a Neanderthal, with buring him around and facing and near the campfire, and the rising sun, feasting at his funeral, (small animal bones picked clean throw haphazardly in the grave), flowers surrounding him, (seeds and pollen) covering him with red ochre, the sign of life, warmth and blood, andin the birth position (fetal).
So, it is fairly apparent that Neanderthal was a believer, perhaps the Creator made himself known to early man as well, as I say in my STBP book, THE QUEST FOR GNOSIS.
BUT, ALAS, PROBABLY NOT IN OUR LIFETIME. INTERESTING THERE WAS AN ARTICLE ON ANOTHER LOST CAUSE OF EINSTEIN, THE UNIFIED FIELD THEORY HAS NEW HOPE. I DID MNOT HAVE TIME TO READ IT, BUT I SKIMMED AND IS SOUNDED PROMISING, PROBLEM IS THAT UNLESS A SCIENTIST WROTE THE ARTICLE I AM SKEPTICAL. WRITERS SANS SUCH BACKGROUND USUALLY DON'T GET IT RIGHT. UNIFIED FIELD THEORY IS THE BASIS OF EINSTEIN'S CLAIM THAT THE QUANTUM IS NOT A SHAKE OF THE DICE-CHAOS AS BOHR INSISTED, AS EINSTEIN SAID, "GOD DOES NOT SHOOT DICE WITH THE UNIVERSE."
DESPITE THAT COMMENT BY EINSTEIN., GOD COULD AND MIGHT SHOOT DICE WITH THE UNIVERSE, BUT NOT ULTIMATELY. I THINK THE QUANTUM WILL SHOW ORDER, BUT THE STRING OF IT'S MAGNITUDE IS BEYOND OUR EXISTENCE TO DISCOVER THE PATTERN OF REPETITION. UNTIL THAT CAN BE DISCOVERED, IT IS UP IN THE AIR, AND FINDING IT MAY TAKE BILLIONS OF YEARS, FOR IT MAY BE THAT LONG A STRING, EVEN AT LIGHT SPEED.
HOWEVER, IF Gödel is correct, we could trace it down through the quantum via the elusive Tachyon.
take the crystal off the Rolex and break the hand. Then break your hand. See which one takes longer to heal.
That's the difference between a dead watch and a life form -- the latter is an active process. They are two different things entirely, and can't be compared in that way. Once chemicals combine in such a way as to constitute a self-organizing process -- call it life -- it tends keep on going and diversifying.
Forget about complexity -- it's irrelevant; it's the differences at the most simple levels which must be looked at. Consider a prion as one example -- reproducing and self-organizing, and yet not generally considered to be alive, such as a virus is, but more like the way salt crystals form by manipulating the NaCl molecules in close proximity in the solution. They aren't alive -- but they are self-organizing. Other minerals can crystalize into very complex shapes, and with various molecular configurations. That's one part of what would happen for something to become 'alive'. This is the sort of thinking one should engage in to understand evolution. Think "RNA".
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Blue Pilgrim (0 articles, 3 quicklinks, 2 diaries, 998 comments)
on Saturday, June 30, 2007 at 7:38:21 AM
Prions are a very interesting example. Research has shown that they are not entirely unlike “ice-nine” from Kurt Vonnegut’s novel Cat’s cradle. Ice nine was said to be a strange form of ice that was self perpetuating… when a normal molecule of water came in contact with a molecule of ice-nine, the water would convert to ice-nine.
Vonnegut was prescient. Prions are mis-folded proteins found in the brain. The normally folded versions work just fine, and don’t have any negative effects. But if one of the protein molecules mis-folds in just the right way, it becomes both inactive at it’s normal job, and also becomes a catalyst for the mis-folding of more of the same type of protein. It acts like a template that makes other copies of the protein mis-fold and stop functioning. It sets off a cascade of protein mis-folding, which leads to the disease (mad cow disease, CJD, etc.).
So it is not life per se, it is a self-replicating protein denaturing process. Very odd stuff, and not a mistake you would expect a perfect, all-powerful creator would make.
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John R Moffett (71 articles, 11 quicklinks, 2 diaries, 523 comments)
on Saturday, June 30, 2007 at 9:39:55 AM
John, interesting article as usual and Gormly, God lives, but the blind and those lacking the gift of Enlightenment cannot see him, though the evidence of His existence is everywhere and He made the minds of those who made the Irrelevant and expensive watches created by Blind Watchmakers, about which the adroitly, supercillious, and bellicose, Ricard Dawkins, rants on in his inamicable, and inconsistent, God hatred, in which in one moment he says there is no God and in the next curses the heretofore non-existent Creator for the Holocaust. He needs to make up his tortured mind if he doesn't believe or is following the accursed ailment of the afflcited, which hate the existence of the Creator, wrongly blaming Him for man's own stupidity. In one breath he denigrates the non-existent and in the other, while cursing the Holocaust he wants to do to Christians and other benign believers, what the Nazi's did to the Jews and many others. I applaud his Noble Prize, but his NoGod argument is based upon, Swiftboating God and all who believe, indluding the intelligent believers and he is Naďvely pursuing the childish game of "the worst insult is to pretend one does not exist." Boy, that is a brilliant ploy, I am certain he fools us all and God with that one!
Gentlemen, I don't know about you but I have had a belly full of Wikapedic pronouncements in patronization of others with academic credential beyond reproach, and expertise gleaned in 5 minutes from the hallowed and often erroneous halls of Wickapedia.
I prefer, if smoke is to be blown up my trousers, that Paris Hilton, Monica Bellucci, Naomi Watts and Laura Harring do the blowing of smoke there-up. So I am passing to go watch the Cubs and Milwaukee pound lumps on each other.
I am going to refrain from bringing my academic credentials into such discussions in future because I am tired of the knowitallism of the adherents of the Wickapedic University of irrelevance.
Pete
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Professor Emeritus Peter Bagnolo (144 articles, 1 quicklinks, 85 diaries, 1112 comments)
on Saturday, June 30, 2007 at 10:13:21 AM
But we do not agree that little has changed in man in the past 2000 years. For one thing, science has proved that the average height of a man in Christ's time was about five feet tall; now days it is around 5-9 and growing.
We can attribute that to the dominant and recessive genes all of us have. Genes for tall or big are dominant, so the odds of an offspring being taller or bigger than a parent is 3 to 1. Dark is dominant, so the chance of having dark hair as opposed to light hair is also 3 to 1, as is having a ruddy complexion as opposed to a light complexion. That is how evolution works; over extended periods of time organisms change.
When one species diverted from another species had to be well in the past when common ancestors were much less developed than they are now.
The Bible does not discount evolution; in fact, if you read the stories correctly, the Bible tells us that evolution is true.
Will explain in a to-come article.
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tabonsell (26 articles, 0 quicklinks, 18 diaries, 205 comments)
on Saturday, June 30, 2007 at 8:02:17 PM
