RufusAtticus

I didn't know there was just one.

Doubting Didymus

That definition has always confused me. Could you explain what evolution between species is, exactly? May I ask for examples of macroevolution of this kind?

pz

I'll have you know I'm the resident cranky, virile, mature man.

And I was going by the fact that Jim called himself a Bio/Chem major. Well, that and the fact that he's got kind of the christian home-schooled college freshman attitude and level of knowledge.

Conchobar

It appears the majority of those posting here really believe in macro-evolution as an explanation for the origin of life on earth.

I "believe" in the fact of evolution much like I believe in gravity, spherical Earth, Heliocentric solar system, moving crustal plates called tectonic plates originating from crustal rift zones that can be seen and distances moved can be measured. I hesitiate to call it belief but knowledge. Principles of Evolution have lead to great medical breakthroughs for innocent children that you would wish to deny in favour of innane Biblical superstition.

I have some questions for those who truely believe in random chance evolution for life origins.

Like most creationists you have a simple minded view of mutations. It is not chance randomness but the properties of molecules, molecular bonding, nucleotide lysing, repletitions, replications, translocations, transposons, viral intrusions all to result in many different chance mutations. Those will mostly fail but the few that are successful will propagate those genes. That is how macro or micro evolution works. That is how classes of animals evolved from other classes, orders from other orders.

Fish to Amphibian Transition (Macro-evolution)

Copyright 1997 G.R.Morton. This may be freely distributed as long as no change is made to the text and no charge is made.

http://www.glenn.morton.btinternet.co.uk/transit.htm

Creationists claim that there are no transitional forms. This claim is made over and over as if it were a mantra. The plain fact is that there are transitional sequences but they never discuss the details. This is a sequence of fossils which occupy the transition from fish to amphibian.

378 MYR ago- Panderichthys--These are lobe-finned fish. Panderichthys was a rhipidistian,osteolepiform fish. The skull bones of these fish are bone for bone equivalents to the skull bones of the earliest tetrapods. (Carroll 1988, p. 160). These are the only fish whose fin bones fit the tetrapod pattern of humerus, ulna and radius in the forelimb and femur, tibia and fibula in the hindlimb. (Thomson, 1991, p. 488), Yet these limbs still have fins on them (Coates, 1994,p. 174). Their brain case is so much like that of the earliest tetrapod, they were originally classified as tetrapods until a complete skeleton was found. Then is was proven that they were really still fish. (Ahlberg and Milner, 1994, p. 508). This fish also had lungs and nostrils (Vorobyeva and Schulze, 1991, p.87) but also had gills. These things really looked like tetrapods until you see the fins. The teeth had infolding enamel which is identical to that of the earliest tetrapods. Unlike all fish but like the tetrapods, the Panderichthys have lost the dorsal and anal fins, leaving 4 fins in the place where legs would be in the Tetrapods.(Ahlberg and Milner, p.508). This contradicts Gish's claim that there is no fossil which shows loss of fins. (Gish, 1978, p. 78-79). Unlike fish, Panderichthys had a tail, like the amphibians with the fins stretched out along the top (Carroll, 1995, p. 389; Carroll, 1996, p. 19).
This is not a Panderichthys, but it is a related lobe-finned Devonian fish out of my personal collection. It gives some idea of what they looked like.


Panderichthyids and all other osteolepiform fish had a choana, a hole between the nasal passage and the mouth. This hole is missing in all other lobe-finned fish. It allowed air to pass from the nose into the mouth.. But Panderichthys also had external nostrils which were in the same position as those of the early tetrapods. (Schultze, 1991, p. 58). The lower jaws of panderichthyids had broad coronoids with fangs (Ahlberg 1991, p. 299)

370--Fish similar to Sauripterus. A very recent discovery in Pennsylvania by Daeschler and Shubin (1998, p. 133; Kinney, 1998) is of a fish which has fins, which is not unusual, except that inside of the fins were 8 fingers attached in a similar way to those of the earliest amphibians (see below). While many doubt that this creature is on the direct line of descent between fish and amphibians, the existence of fins with 'fingers' is illustrative of the fact that intermediate forms (broadly defined) do exist. Interestingly, as we shall see some of the earliest amphibians also had 8 digits on their hands.


368-Elginerpeton is a very primitive tetrapod found at Scat Craig, Scotland. Its lower jaw had coronoid fangs as did Panderichthys but they were smaller (Ahlberg 1991, p. 299). The very primitive limb bones found with it include an Ichthyostega-like tibia and an ilia and shoulder girdle comparable to the future Hynerpeton. There are no hands or feet found with the fossil so while the animal is quite tetrapod like in the parts which have been preserved, the final proof of its tetrapod status is missing. (Carroll, 1996, p. 19)

368 MYR- Obruchevichthys was found in Latvia and Russia but is only known from a partial mandible. The similarity between this mandible and Elginerpeton caused Ahlberg (1991) to reclassify this as a tetrapod. This creature also shows the coronoid fangs of the Panderichthys but they were also smaller than the panderichthyid fangs. Daeschler notes that this animal also has the parasymphysial fans of a tetrapod. (Daeschler, 2000, p. 307)

365-363 MYR -Hynerpeton-more advanced legs and pelvic girdle than Ichthyostega. (Carroll, 1996, p. 19) The coronoid fangs are not present. It lacked internal gills (Daeschler et al, 1994, p 641). There is no mention of feet having been found in Daeshler's report. The shape of the pectoral girdle implies both an aquatic and a terrestrial lifestyle.

365-363 MYR -Densignathus rowei--known only from the jaw but it is transitional between fish and amphibians. It has the parasymphysial fang of a stem tetrapod but also the coronoid fangs of a fish. As noted above Daeschler says this combination is also found in Obruchevichthys, Ventastega and Metaxygnathus. (Daeschler, 2000, p. 307). The earlier fish had a closed manidbular canal while the early amphibians had an open mandibular canal. Densignathus rowei is intermediate with a partially enclosed mandibular canal. Once again a transitional trait.

363 MYR-Ichthyostega-- Is the first animal with feet but the feet are different than most tetrapod feet. They are much like Acanthostega but has 7 digits on his hindlimb. His legs were only good for being in water. They could not support his weight. (Coates and Clack, 1990, p. 67) These are half evolved legs since they have more digits than the normal tetrapod but fewer bony rays than the fish and they are unable to support the weight. This contradicts Gish's statement that there are no half-evolved feet. (Gish, 1978, p. 79) . Ichthyostega had external nasal openings and a choana like that of the Panderichthys (Schultze, 1990, p. 35). He has lungs and gills. His tail was long with fins above and below like that Panderichthys and Acanthostega. (Carroll, 1992, p. 46). His legs were tetrapod having humerus, ulna and radius in the forelimb and femur, tibia and fibula in the hindlimb. (see diagram Carroll, 1992, p. 46).

363 MYR- Acanthostega- has four legs, lungs but still has internal gills. (Coates and Clack , 1991, p. 234) He has 8 digits on his front leg (see second picture below); seven on his back feet. (Carroll, 1995, p. 389) His legs could not support his weight either. (Coats and Clack, 1990, p. 66-67). Ahlberg (1991, p. 301) points out that the front legs were more fish-like than the back legs. He has fishlike lower arm bones (Coates and Clack 1990, p. 67). Once again, contrary to Gish (1978, p. 79), these are still half-evolved legs. He also retains a caudal fin (Coates, 1994, p. 175) and an elongated tail with fins stretched out along the top. (Carroll, 1995, p. 389). The stapes, the bone which eventually became part of the hearing apparatus in tetrapods was still used for ventilation of the gills (Clack,1989, p. 426).

Acanthostega served from http://www.sciencenews.org/Sn_arc99/5_22_99/bob1a.jpg

Reconstruction of Acanthostega gunnari is reproduced here by the kind permission of Dr. Jennifer Clack

One thing that the earliest tetrapods lacked were hands that could flex. We can curl our fingers and toes because of the arrangement of the tendons in our digits. None of the above tetrapods could do this simple trick because they lacked a notch in the flexor surface on the phalanges. Because of this, walking on a rocky surface, which requires the ability to curl the paws around various obstacles, would have been difficult for the early tetrapods. Acanthostega and Ichthyostega would only have been able to bend their hands slightly (Monastersky, 1999, p. 329). Thus, while they had hands, they were partially evolved hands. It wasn't until the evolution of Casineria kiddi, that these notches are found on each phalange. (Paton et al, 1999, p. 512)

350 MYR ago. Pederpes finneyae- This creature was discovered at Dumbarton, Scotland. It has 5 toes on each foot with the exception of a small relict finger/toe on the forepaw. Because of this, this creature is transitional between the later amphibians and Acanthostega and Ichthyostega discussed above (Carroll, 2002, p. 35). This creature has a primitive stapes, the bone used in hearing and it resembles that of Acanthostega rather than those of the later amphibians. The expanded triangular flair on the ribs resemble those of Ichthyostega. (Clack, 2002, p. 74). But, unlike the early tetrapods this creature has a "clearly distinguishable metatarsals that are bilaterally and proximodistally asymmetric." (Clack, 2002, p.75). This is a trait which it shares only with the later terrestrially adapted amphibians. Thus, once again, this creature shows intermediate or transitional traits. Those who erroneously claim transitional forms don't exist, haven't looked at the data.

340 MYR ago. Fully evolved amphibians. Amniator, Crassigyrinus, Loxommatoidea, Temnospondyl, Colosteidae, Acanthracosauria.



All of nature shows remarkable complexity in regards to intercellular structure and design i.e. protein or DNA. The structure of protein as it is exists in nature makes the probability of random/chance origins quite hard to accept.

Only for a non-biochemist.

For example the average protein has some 300 amino acids hooked together by peptide bonds and are arranged in no certain "logical" sequences. These sequences have to be exact without mistakes for the protein to work, especially when it comes to enzymes. There are 20 amino acids that comprise all proteins in nature. For random chance to have worked you have to believe that these complex little molecules would have to have combined magically in the right sequence all at once and to have magically wound up in a cell membrane which is by the way protein and be stero-chemically correct .

Random mutations millions of times over half a billion years produced many combinations that were incorrect. The success rate was maybe 1 in a million. Look at the number of human spontaneous miscarriages because of a coding error.

All of nature uses only left handed amino acids to build its proteins. Randomness by its nature should have produced both left and right handed amino acids , but we find none in all of nature.

In it quantum randomness the initial products were Levostereostructured. There was a 50-50 chance it could have started with R proteins but it was L. A mix of the two would have been incompatible with successful life. It had to be R or L and L was randomly the one that succeeded first.

Its like flipping a coin thousands of billions of times and it always comming up heads as an illustration of how hard it would be for this to happen.

You don't understand. Flipping a coin has a 50-50 chance of heads every time. To have a million planets combine make amino acids and amines, there would be a similar 50-50 chance that it would be R or L. We just happen to be on an L-stereo world of life. In the Pre-cambrian nature may have tried R forms and L forms but L forms won the race for unclear reasons. On Alpha-cenaruri 3 it might be R that won.

As a matter of fact if you consider the probability of taking 20 amino acids and combining them exactly correct into a chain 300 long ( there are some much longer) you come up with a staggering figure thats impossible to comprehend, 1X10 to the 600 power.

That is Voodoo mathematics. When we make templates for a microchip, we can produce it thousands of time without error. We can have typesetters on old newspapers make a 30 page news paper with thousands or tens of thousands of characters. And each inking and pressing produces the 30 page character sequence accurately. You math is based on no premise or axiom.

To give you some scope on how large this number is there are only 1x10 to the 25 power grains of sand on this planet, each time you add a zero you multiply that number by ten, its just to large to imagine.

And purely conjectural.

DNA is much more complex than this. There are over 300 billion combinations for the four nucleotides to hook up in the human genome. It take less than three bad hook ups to cause a fatal result in the animal it happens in , as a matter of fact science has never observed a usefull mutation in cellular biology yet.

Science doesn't always require a process occurring over millions of years to be observed in the short human life span. The fact that errors occur in the millions every year show that it is not a perfect system. Mutations are common. One successful one was the new salmon species in the northwest USA when a stream was diverted 70 years ago separating a species into two new ones. Evolution is more of a history than a lab experiment on an afternoon.

Humans are the best transtional fossils. Transitional fossils especially the ones between orders and famililies cannot be challenged by fundies of the CRI. Humans begin as single cells. Hox genes make certain cells located at different parts of the ball of cells to differentiate. We go through a worm stage of segmented animal, then we form a notochord found normally only in amphioxus and Cambrian Pikaia proto-chordates. Our neural tubule develops a similar nervous sytems with crossed motor systems like Amphioxus. Then we develope gills, limb buds and a tail like lobe finned fishes. Then the lobe fins develope arms and legs. The gills get recycled into ear parts and larynx. New Hox genes regulate this. The Notochord reabsorbes as the vertebral column begins to form and the tail is reabsorbed. We go from fish to amphibian, to reptile. Our brain goes from a medulla and spinal cord, to amphibian brain stem, to reptile brainstem and diencephalon. then the Archaorcortex and Palaeocortex of primitive mammals develops adding on to the existing structures. Finally the primate advanced neocortex developes adding on mainly to frontal and parietal lobes. In other words human embryology is a living textbook of our evolution. To add icing to the cake, the human genome project has shown us (humans ) to contain genes of ancient ancestors that we never bothered to discard. The Genome is volume II of the Human Textbook of Evolution.

Mapping the human genome is reconded to be as significant an accomplishment as going to the moon. The chicken or the egg factor comes in here too when you consider the fact that to have DNA you have to have protein and to have protein used inside the cell you have to have DNA.

Mitochondrial structures older than cells have been found in the 750 million year old fossil beds. These contain DNA. Now the DNA doesn't survive but proteins do by attachment to the bony surfaces. We can world backwards from the polypeptides to the nucleotide sequences that made them. Now finally we can truthfully say that Evolution is a fact not theory. The only theories are the various mechanisms at work in speciation mutational mechanisms.


The question I have for anyone is this, explain how the complexity just mentioned could have been the result of random/chance evolution?

I did that above. Nucleotide sequences break, rearrange, have insertions, translocations, transposon carriers, lytic enzymes. We are able to reproduce many of these in my lab in Belfast.

Theres not enough atoms in the universe to be given an eternity of time to combine to cause a single protein to form little alone life.

Obviously there are more than enough atoms, because it happened. We are here discussing it. Atoms have intrinsic properties Na+ (corrosive metal) unites with Cl- (toxic gas) to produce nutritionally necessary table salt. The more complex molecules have new sets of complex intermolecular reactions and bondings. None of this is breaking news, European schools have taught this for 50 years or more, while you guys have been reading bible quotes of superstitious rubbish.

There are many agnostic scientists in genetic research but you won't find too many atheist working in cellular/genome research. Its hard to accept fiat creation but they definitely don't accept macro-evolution as an explanation for the origin of life.

Thats odd. I am a genetic researcher Ph.D. and I dn't know any of those guys you mention. Are they all Americans and in Alabama? Macro-evolution is an accepted fact among all leading genetic researchers, palaeontologists, zoologists. We know it happened because of the hundreds of transitional types (not species but actual orders.) That is a macro as you need. How about Reptiles to Birds? This is Order Reptilia to Order Aves. MACRO, MACRO.

Harpagus bidentatus

IBEROMESORNIS
(pronounces eye-BER-oh-mes-OR-nis) Iberomesornis (meaning "Iberian=Spanish intermediate bird") was a small, early, toothed bird that lived during the early Cretaceous period. It was capable of powered flight. It had tiny, spiky teeth in its beak and was the size of a sparrow. Its hip was primitive compared to modern birds; its ilium, ischium, and pubis were all parallel and directed backward. Iberomesornis was named by paleontologists Sanz and Bonaparte in 1992. Fossils were found in Spain. The type species is I. romeralli.

ICHTHYORNIS
Ichthyornis (meaning "fish bird") were 8 inch (20 cm) long, toothed, tern-like, extinct bird that date from the late Cretaceous period. It had a large head and beak. This powerful flyer is the oldest-known bird that had a keeled breastbone (sternum) similar to that of modern birds. It lived in flocks nesting on shorelines, and hunted for fish over the seas. Ichthyornis was originally found in 1872 in Kansas, USA, by a member of paleontologist Othniel C. Marsh's Yale University expedition. Fossils have been found in Kansas and Texas, USA and Alberta, Canada. (Subclass Odontornithes, Order Ichthyornithiformes

HESPORNIS
Hespornis (meaning "western bird") was an early, flightless bird that lived during the late Cretaceous period. This diving bird was about 3 feet (1 m) long and had webbed feet, a long, toothed beak, and strong legs. Although it couldn't fly, it was probably a strong swimmer and probably lived near coastlines and ate fish. Fossils have been found in North America .


I personally feel it takes more "faith" to believe in macro-evolution than it does to believe in fiat creation.
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Evolution has litterally tonnes of evidence, anatomical relationships that are too similar to ignore. Now we have the protein and genetic evidence that puts all doubt in intelligent persons to rest. With all of this overwhelming evidence in our very cells, our embryology, our genetics, the mineralised fossils, what else explains all of these hard facts. The humourous part of the Anti-Science people is that they have no alternative explanation for biology and speciations, extinctions and expansions of new forms so many times over history. Give me an alternative explanation.

Exclude the Bible because I find it to be full of errors and lies, contractions and just silly ignorant superstitions. Worse yet it is the most morally depraved book ever written. It is filth and glorifies violence, debasement of women, in a most degrading way.

Also exclude CRI's deliberate hoaxes like the dino tracks along side of human tracks. That was debunked 20 years ago.

Near Glen Rose, Texas, the river bed of the Paluxy river is still revealing the astonishing sight of what apparently is human and dinosaur tracks together in stone. The rock formation is the Cretaceous. In 1970, James Ryals, who had been cutting out tracks and selling them since the 1930s, was interviewed. He reported the human tracks as mostly barefooted, but sometimes encased in some form of wrapping. The stride varied from two to seven feet. There are human tracks crossing dinosaur tracks, and dinosaur tracks which have blotted out human tracks in sequence.

Excavation of tracks show a compressed layer pattern underneath as one would expect if they are genuine. A scientist who did not examine the evidence ruled out the possibility that the tracks were human. A professor of medicine from the Unversity of Illinois examined the tracks and was convinced that they were genuine (CRSQ , 1970, 7:3, p.142; 1970, 7:4, p.246; Ryals, undated). Some years later at least some of the supposed human tracks were definitely shown to be dinosaur tracks. In the past 20 years many additional discoveries have been made to add to the controversy. Many books and articles treat these finds, both for and against their authenticity.

We must say that reports of footprints call for the utmost caution. Many people are imaginative creatures and with a little effort they can see almost anything patterned in worn rocks. Some rocks erode in a curious manner which could leave depressions much like footprints. No one questions the dinosaur footprints, however. The topic is too fascinating to pass by. Perhaps new finds will clarify the situation.

http://www.rae.org/ch07tud.html

I hope we can get back to honesty in the discussion of science and expand our knowledge. We need to free our minds from the chains of ignorance and the shackles of superstition. Science gives us the best available answers. Mythology is fantasy. (Biblical Genesis in Mythology).

Conchobara

lpetrich

As to the DNA-protein interdependence conundrum, a favorite way out is the "RNA world" hypothesis, in which RNA molecules served as enzymes. This gets rid of the transcription and translation steps, greatly simplifying the origin problem.

Protein was invented as a fancy cofactor for RNA enzymes or ribozymes; it eventually became the primary enzyme, with RNA and RNA-ish molecules only persisting as cofactors. This takes care of RNA -> protein.

DNA is a modification of RNA that is used for master-copy duty. This takes care of DNA -> RNA.

Thus, we have all the pieces of DNA -> RNA -> protein.

Wounded King

I have met a few biochemists who seem ignorant of the fundamentals of evolution. Perhaps they feel that anything which involves whole organisms and cant be given an affinity constant is beneath their notice.

Can I be anti-pope?

RufusAtticus

Biochemists! Heck, in my Molecular Evolution course, the 2nd year molecular genetics grad students needed to be told the fundamentals of evolution.

pz

Only if you are a fervent Developmental Systems Theorist.

(I just realized...the Inquisitor is probably going to have to torture himself for his heresies. Damn.)

Jim Larmore

Obviously the subject of Macro-evolution is controversial to say the least!!!! I will study more on evolution so I can intelligently debate this with you guys , but I still have more questions before I go bury my head in the books.

No one has really answered or satisfactorily resolved the probability problem. I've been called a liar and a cheat here but math doesn't lie, do the calculations yourselves. Given 20 amino acids with an average of 300per protein or more and see what you come up with for possibilities. Evolution still claims random origins does it not? Explaining away the levo orientation of the molecules for living systems shows incredible gullableness. There should be right now an even distribution of both levo and dextro amno acids if random selection was the modality for lifes orgins. We don't see this, only levo oriented molecules exist in living systems . How come no one wants to talk about the origins of life? Theres not enough time or matter to make all this happen from chaotic randomness, saying" well it did "doesn't cut it. Obviously" it did" I mean duh!!! Logic alone tells me there had to be a designer and the evidence is right there in the cell.

How can you explain the vast variation in numbers of chromosomes in different species and then say they had common ancestors? It doen't make sense especially considering how complex DNA is. This is the one of the main obstacles for Macro-evolution.

Last but not least there is one final question I must ask. How do you explain life? Life is a miraculous thing an unattainable entity that man has never and never will be able to replicate. Life exists because a designer made it so. You can make some very simple proteins with great difficulty in the lab but no one has ever made even simple single cellular life. If man in all his wisdom and technology can't even make a one celled life form , how could blind inanimate minerals and chemicals do it given an eternity of time? I'm sorry but you Ph.Ds and lay evolutionist have yet to really definatively explain these questions. I'm going to study. See ya.

Wounded King

Dont you look at the news jim? Researchers have already produced a synthetic polio virus and a number of labs are working on developing synthetic unicellular life or organism.

As to your probability calculations, it has been pointed out several times that random chance, or chaotic randomness, is not the proposed mechanism of evolution. Nor does it claim random origins, in fact it doesnt claim anything about abiogenesis, as has been previously mentioned.

As to the number of chromosomes being a good argument against evolution I can only say huh!! Duplications of genes, chromosomes or indeed entire genomes is a vital mechanism in evolution. Without these duplications there would have been no leeway for the evolution of many diverse members of related protein families. How would you explain the difference in Hox clusters between Drosophila (1) and Humans (4), it seems fairly obvious that at least one or two duplications of this particular region of the genome would explain it. Read a bit about ploidy in plants and you will see that multiplication of chromosomes is not some impossible barrier to evolution, or look at the diploid (tropicalis) and tetraploid (laevis) species of xenopus!