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To: Ichneumon

Good God, man!
Your graph of "gray" shadings????
Now we're back to "gradual"?

Where are the all transitionally "gray" fossils, then?

Each and every fossil, can only be, one damn frame, one thing, period. Correct?
Just one "space", on the continuum....so don't look at 'em
as----?

Ok, so no black/white, true/false, just continuing gradual change...
I'd love to buy into that,

EXCEPT---

This so, so gradual process, taking eons to fully transpire,
leaves out ALL major form shifts? Then goes back to slow change and adaptation?

HA! You guys talk yourselves into some steep piles, justifying it six ways from Sunday when pressed---but never addressing the point! (just more fancy dodging)

I know you hate this "where are these" shaded/transitional fossils question. It's still there...rhetoric won't kill it off. Your own circular rhetoric always brings you back.
Please, have the intellectul honesty to FACE IT THIS TIME!

Can you not see the logic to this question, in light of your lecturing?

It's shaded when it suits you...

Where are the gradual shifts in basic form?
If things are so gradual?

If it's an widespread, on-going process, examples, one would think, should abound.

That's not either/or thinking! That's allowing for the gradual shifts the theory should show proofs of.

The proofs are thin, if that (non-extant,is more like it!)

Given the PROFUSION of life forms, we cannot accept just "a few" examples, when there should be THOUSANDS.

Or do these shades of gray pertain only to abiogenisis?

Not according to you;
"The change occurred *gradually*, across *many* generations, from a very "lizardlike" form, eventually to a "lizardish with vaguely mammalian features" form, to eventually something that people might consider "mostly mammal", and sometime down the road (but with no clear "aha" dividing line) to something"

Which of course, leads us right back to where we started.

I guess you can't see it.

Too brainwashed....


672 posted on 02/02/2005 12:13:16 AM PST by 7MMmag (has Traficant been "beamed up" yet? he use to always say, "beam me up!", well? where is he?)
[ Post Reply | Private Reply | To 332 | View Replies ]


To: 7MMmag; Alamo-Girl; PatrickHenry; betty boop; tortoise; Physicist; RadioAstronomer; jennyp; ...
Good God, man! Your graph of "gray" shadings???? Now we're back to "gradual"?

Try to be coherent.

Where are the all transitionally "gray" fossils, then?

Right where they've always been, being studied by evolutionary biologists, while the creationists sit around slapping each other on the back and cheering on each other's ignorance instead of picking up a few science journals and LEARNING SOME SCIENCE for a change.

You know, sort of the way you yourself couldn't wait to jump on my post and start making fun of it, without bothering to read the thread first and see that I had already made a long post correcting *another* person's lack of education on the *SAME* question. Nor did you bother to check my profile page before you decided to call me stupid and brainwashed and dishonest, to see whether you might have been foolishly in the position of a six-year-old trying to pick a fight with an oncoming semi...

In short, you're too arrogant and reckless to notice that I've already answered your question in detail on this thread, so you've already made yourself look lazy and foolish, and you are *way* out of your league on this subject.

So why am I giving you both barrels just for not knowing what in the hell you're talking about? Because a) in reply to my civil post to Alamo-Girl, you chose not to just be civil and ask questions or state your case, you chose to taunt and ridicule and try to belittle me (and all evolutionary biologists) as being dishonest, blind, or "brainwashed" (your word), and b) I've had it up to here with the non-stop waves of obnoxiously arrogant empty-headed know-nothing anti-evolutionists, as well as the shocking numbers of lies that many of them tell with absolutely no shame.

So hold on tight, it's going to be a bumpy ride. (Spectators who are disturbed by scenes of extreme textual violence may wish to leave the room now.)

Each and every fossil, can only be, one damn frame, one thing, period. Correct?

Sure, just as I said in my post. Way ahead of you, kid.

Just one "space", on the continuum....so don't look at 'em as----?

Hey, if you can't even complete your own question, don't expect me to do it for you.

Ok, so no black/white, true/false, just continuing gradual change... I'd love to buy into that,

Why do I doubt that?

EXCEPT--- This so, so gradual process, taking eons to fully transpire,

I didn't say "eons", nor does it usually take "eons". Hallucinate much? Or are you just that grossly ignorant of biology?

leaves out ALL major form shifts?

Not what I said. Try cutting down on your medication. And go back and read my post which I linked you, which *already* shows what a stupid and ignorant question you just asked. Short answer -- "no, no it doesn't, you dolt, which you would have already known if you had bothered to read at least as many science journals as creationist pamphlets."

Hint: Trying to "learn" about science from creationist sources is like trying to "learn" about conservatism from Michael Moore movies. Think I'm exagerrating? Then read the material and links in THIS post of mine.

Then goes back to slow change and adaptation?

Hey, moron -- evolutionary change on the human timescale is slow. Evolutionary change on the geological timescale is pretty quick. That's no contradiction to anyone with a working brain. After becoming established and adapted to their niches, species can often have periods of relative stability, though. This is a necessary consequence of the mathematics underlying the process of evolution, which you'd know if you actually bothered to study biology instead of the ravings of "Dr. Dino" and friends.

HA! You guys talk yourselves into some steep piles, justifying it six ways from Sunday when pressed

Yes, we *do* justify it in multiple ways, by experimentation, by evidence, by testing predictions, and so on. Thanks for noticing that our field is justified by the evidence in multiple independent ways.

---but never addressing the point! (just more fancy dodging)

If you would *MAKE* a point instead of just vaguely rambling and giggling, I'd be happy to address it.

I know you hate this "where are these" shaded/transitional fossils question.

I don't hate it at all. There are tens of thousands of them, as anyone who has looked at the paleontological literature knows full well. But that, of course, leaves out the anti-evolutionists, who don't bother looking at what they "know" must be "mistaken", so they continue to wallow in their ignorance.

Here are a few hundred for you if you really would like to educate yourself. But somehow I doubt that becoming educated is high on your list of priorities, since it would get in the way of your arrogance and desire to laugh at all those "stupid scientists" and so on...

It's still there...rhetoric won't kill it off.

Yes indeed, the transitional fossils are still there, and your gibbering rhetoric won't kill it off. Deal with it.

Your own circular rhetoric always brings you back.

You "forgot" to mention how, precisely, my "rhetoric" is allegdly circular, and what it "brings me back" to exactly. You're going to feel pretty silly when all that tequila wears off.

Am I to believe that you can barely even form a coherent train of thought, but somehow you're able to grasp the entire field of biology better than those silly folks who spend their entire lives researching it? Just how gullible do you think we are? And how arrogant are *you*? Hey, feel free to tell me what's wrong with the DNA evidence consisting of endogenous retroviruses as it relates to common descent. I mean, it seems pretty convincing to *me*, but there *must* be something wrong with it since you know evolution is wrong, so since you're the "expert" in this field, feel free to explain the flaw in it to me... Hello? We're waiting...

Please, have the intellectul honesty to FACE IT THIS TIME!

I face know-nothing loudmouths like you all the time. Bring it on.

Can you not see the logic to this question, in light of your lecturing?

You had a question in there somewhere?

It's shaded when it suits you...

No, it's what the real-world evidence indicates, and I'm intellectually honest enough to follow where the evidence leads as it reveals the nature of that "reality" thing you must have heard about between Sterno binges.

Where are the gradual shifts in basic form? If things are so gradual?

*Still* haven't read the thread or my profile page, I see...

If it's an widespread, on-going process, examples, one would think, should abound.

And they do. The question is, why are you so amazingly and completely ignorant of them? Oh, right, because they don't print them on bottles of cheap wine.

That's not either/or thinking!

No, that's just your ignorance.

That's allowing for the gradual shifts the theory should show proofs of.

Yes. Exactly. (A tiny light bulb may *someday* turn on in your brain yet -- if it doesn't die of loneliness first.)

The proofs are thin, if that (non-extant,is more like it!)

Do tell... And you "learned" this lie from where, exactly?

Given the PROFUSION of life forms, we cannot accept just "a few" examples, when there should be THOUSANDS.

Yes. And that's *exactly* what we have found (see links above). OOPS, it seems you just shot yourself in the foot. Moron. Here, you'll need one of these:

Or do these shades of gray pertain only to abiogenisis?

Not at all, which is why I already discussed them pertaining to speciation. Can you not *read*?

Not according to you; "The change occurred *gradually*, across *many* generations, from a very "lizardlike" form, eventually to a "lizardish with vaguely mammalian features" form, to eventually something that people might consider "mostly mammal", and sometime down the road (but with no clear "aha" dividing line) to something"

Yes. Exactly. I was correct again, as usual. But thanks for bringing up the lizard-mammal transition -- would you like to see some of the fossils (you know, just in case it wasn't *already* painfully clear how uninformed you are)?

Example 2: reptile-mammals

[Figure1.4.1 (cartoon of vertebrate jaws)]

Figure 1.4.1. The jaws of three vertebrates—mammal, therapsid, and pelycosaur. A side view of three idealized skulls of mammals, therapsids (mammal-like reptiles), and pelycosaurs (early reptiles). The figure shows the differences between mammal and reptilian jaws and ear-bone structures. The jaw joint is shown as a large black dot, the quadrate (mammalian anvil or incus) is in turquoise, the articular (mammalian hammer or malleus) is in yellow, and the angular (mammalian tympanic annulus) is in pink. Note how, in the reptile, the jaw joint is formed between the blue quadrate and the yellow articular (with the pink angular close by), and how, in the mammal, the jaw joint is formed between the squamosal above and the dentary below. In the reptile, the squamosal is just above and contacting the quadrate. Advanced therapsids have two jaw joints: a reptile-like joint and a mammal-like joint (Figure based on Kardong 2002, pp. 275, reproduced with permission from the publisher, Copyright © 2002 McGraw-Hill)

We also have an exquisitely complete series of fossils for the reptile-mammal intermediates, ranging from the pelycosauria, therapsida, cynodonta, up to primitive mammalia (Carroll 1988, pp. 392-396; Futuyma 1998, pp. 146-151; Gould 1990; Kardong 2002, pp. 255-275). As mentioned above, the standard phylogenetic tree indicates that mammals gradually evolved from a reptile-like ancestor, and that transitional species must have existed which were morphologically intermediate between reptiles and mammals—even though none are found living today. However, there are significant morphological differences between modern reptiles and modern mammals. Bones, of course, are what fossilize most readily, and that is where we look for transitional species from the past. Osteologically, two major striking differences exist between reptiles and mammals: (1) reptiles have at least four bones in the lower jaw (e.g. the dentary, articular, angular, surangular, and coronoid), while mammals have only one (the dentary), and (2) reptiles have only one middle ear bone (the stapes), while mammals have three (the hammer, anvil, and stapes) (see Figure 1.4.1).

Early in the 20th century, developmental biologists discovered something that further complicates the picture. In the reptilian fetus, two developing bones from the head eventually form two bones in the reptilian lower jaw, the quadrate and the articular (see the Pelycosaur in Figure 1.4.1). Surprisingly, the corresponding developing bones in the mammalian fetus eventually form the anvil and hammer of the unique mammalian middle ear (also known more formally as the incus and malleus, respectively; see Figure 1.4.2) (Gilbert 1997, pp. 894-896). These facts strongly indicated that the hammer and anvil had evolved from these reptilian jawbones—that is, if common descent was in fact true. This result was so striking, and the required intermediates so outlandish, that many anatomists had extreme trouble imagining how transitional forms bridging these morphologies could have existed while retaining function. Young-earth creationist Duane Gish stated the problem this way:

"All mammals, living or fossil, have a single bone, the dentary, on each side of the lower jaw, and all mammals, living or fossil, have three auditory ossicles or ear bones, the malleus, incus and stapes. ... Every reptile, living or fossil, however, has at least four bones in the lower jaw and only one auditory ossicle, the stapes. ... There are no transitional fossil forms showing, for instance, three or two jawbones, or two ear bones. No one has explained yet, for that matter, how the transitional form would have managed to chew while his jaw was being unhinged and rearticulated, or how he would hear while dragging two of his jaw bones up into his ear." (Gish 1978, p. 80)

[Figure1.4.2a (cartoon of vertebrate ears)] [Figure1.4.2b (cartoon of vertebrate ears)]

Figure 1.4.2. A comparison of the ears of reptiles and mammals. The reptile ear is shown on the left, the mammal ear on the right. As in Figure 1.4.1, the quadrate (mammalian anvil or incus) is in turquoise and the articular (mammalian hammer or malleus) is in yellow. The stapes is shown in brown. Note how the relative arrangement of these bones is similar in both taxa, in the order of inner ear-stapes-quadrate-articular.

Gish was incorrect in stating that there were no transitional fossil forms, and he has been corrected on this gaff numerous times since he wrote these words. However, Gish's statements nicely delineate the morphological conundrum at hand. Let's review the required evolutionary conclusion. During their evolution, two mammalian middle ear bones (the hammer and anvil, aka malleus and incus) were derived from two reptilian jawbones. Thus there was a major evolutionary transition in which several reptilian jawbones (the quadrate, articular, and angular) were extensively reduced and modified gradually to form the modern mammalian middle ear. At the same time, the dentary bone, a part of the reptilian jaw, was expanded to form the major mammalian lower jawbone. During the course of this change, the bones that form the hinge joint of the jaw changed identity. Importantly, the reptilian jaw joint is formed at the intersection of the quadrate and articular whereas the mammalian jaw joint is formed at the intersection of the squamosal and dentary (see Figure 1.4.1).

How could hearing and jaw articulation be preserved during this transition? As clearly shown from the many transitional fossils that have been found (see Figure 1.4.3), the bones that transfer sound in the reptilian and mammalian ear were in contact with each other throughout the evolution of this transition. In reptiles, the stapes contacts the quadrate, which in turn contacts the articular. In mammals, the stapes contacts the incus, which in turn contacts the malleus (see Figure 1.4.2). Since the quadrate evolved into the incus, and the articular evolved into the malleus, these three bones were in constant contact during this impressive evolutionary change. Furthermore, a functional jaw joint was maintained by redundancy—several of the intermediate fossils have both a reptilian jaw joint (from the quadrate and articular) and a mammalian jaw joint (from the dentary and squamosal). Several late cynodonts and Morganucodon clearly have a double-jointed jaw. In this way, the reptilian-style jaw joint was freed to evolve a new specialized function in the middle ear. It is worthy of note that some modern species of snakes have a double-jointed jaw involving different bones, so such a mechanical arrangement is certainly possible and functional.

Since Figure 1.4.3 was made, several important intermediate fossils have been discovered that fit between Morganucodon and the earliest mammals. These new discoveries include a complete skull of Hadrocodium wui (Luo et al. 2001) and cranial and jaw material from Repenomamus and Gobiconodon (Wang et al. 2001). These new fossil finds clarify exactly when and how the malleus, incus, and angular completely detached from the lower jaw and became solely auditory ear ossicles.

Recall that Gish stated: "There are no transitional fossil forms showing, for instance, three or two jawbones, or two ear bones" (Gish 1978, p. 80). Gish simply does not understand how gradual transitions happen (something he should understand, obviously, if he intends to criticize evolutionary theory). These fossil intermediates illustrate why Gish's statement is a gross mischaracterization of how a transitional form should look. In several of the known intermediates, the bones have overlapping functions, and one bone can be called both an ear bone and a jaw bone; these bones serve two functions. Thus, there is no reason to expect transitional forms with intermediate numbers of jaw bones or ear bones. For example, in Morganucodon, the quadrate (anvil) and the articular (hammer) serve as mammalian-style ear bones and reptilian jaw bones simultaneously. In fact, even in modern reptiles the quadrate and articular serve to transmit sound to the stapes and the inner ear (see Figure 1.4.2). The relevant transition, then, is a process where the ear bones, initially located in the lower jaw, become specialized in function by eventually detaching from the lower jaw and moving closer to the inner ear.

[Figure1.4.3 (cartoon of vertebrate jaws)]

Figure 1.4.3. A comparison of the jawbones and ear-bones of several transitional forms in the evolution of mammals. Approximate stratigraphic ranges of the various taxa are indicated at the far left (more recent on top). The left column of jawbones shows the view of the left jawbone from the inside of the mouth. The right column is the view of the right jawbone from the right side (outside of the skull). As in Figure 1.4.1, the quadrate (mammalian anvil or incus) is in turquoise, the articular (mammalian hammer or malleus) is in yellow, and the angular (mammalian tympanic annulus) is in pink. For clarity, the teeth are not shown, and the squamosal upper jawbone is omitted (it replaces the quadrate in the mammalian jaw joint, and forms part of the jaw joint in advanced cynodonts and Morganucodon). Q = quadrate, Ar = articular, An = angular, I = incus (anvil), Ma = malleus (hammer), Ty = tympanic annulus, D = dentary. (Reproduced from Kardong 2002, pp. 274, with permission from the publisher, Copyright © 2002 McGraw-Hill)

(The above is from 29+ Evidences for Macroevolution, which was already posted to this thread, and which "7MMmag" was too lazy to read before he shot off his mouth and deigned to "educate" us on this topic)

Have I made my point? Has the depth of your ignorance, and the foolishness of your attacking me on this topic sunk in yet? Hmm, somehow I'm not sure -- anti-evolutionists can be *SO* slow to grasp the facts sometimes. So just to be sure, here's another 120mm tank round of scientific knowledge to your head -- maybe THAT will finally penetrate your forehead:

Mammal-Like Reptiles

As previously stated, a succession of transitional fossils exists that link reptiles (Class Reptilia) and mammals (Class Mammalia). These particular reptiles are classifie as Subclass Synapsida. Presently, this is the best example of th e transformation of one major higher taxon into another. The morphologic changes that took place are well documented by fossils, beginning with animals essentially 100% reptilian and resulting in animals essentially 100% mammalian. Therefore, I have chosen this as the example to summarize in more detail (Table 1, Fig. 1).

[Fig. 1a]
[Fig. 1b]

Skulls and jaws of synapsid reptiles and mammals; left column side view of skull; center column top view of skull; right column side view of lower jaw. Hylonomus modified from Carroll (1964, Figs. 2,6; 1968, Figs. 10-2, 10-5; note that Hylonomus is a protorothyrod, not a synapsid). Archaeothyris modified from Reisz (1972, Fig. 2). Haptodus modified from Currie (1977, Figs, 1a, 1b; 1979, Figs. 5a, 5b). Sphenacodo n modified from Romer & Price (1940, Fig. 4f), Allin (1975, p. 3, Fig. 16);note: Dimetrodon substituted for top view; modified from Romer & Price, 1940, pl. 10. Biarmosuchus modified from Ivakhnenko et al. (1997, pl. 65, Figs. 1a, 1B, 2); Alin & Hopson (1992; Fig. 28.4c); Sigogneau & Tchudinov (1972, Figs. 1, 15). Eoarctops modified from Broom (1932, Fig. 35a); Boonstra (1969, Fig. 18). Pristerognathus modified from Broom (1932, Figs 17a, b,c); Boonstra (1963, Fig. 5d). Procynosuchus modified from Allin & Hopson (1992, Fig. 28.4e); Hopson (1987, Fig. 5c); Brink (1963, Fig. 10a); Kemp (1979, Fig. 1); Allin (1975, p. 3, Fig. 14). Thrinaxodon modified from Allin & Hopson (1992, Fig. 28.4f);Parrington (1946, Fig. 1); Allin (1975, p. 3, Fig. 13). Probainognathus modified from Allin & Hopson (1992, Fig. 28.4g); Romer (1970, Fig. 1); Allin (1975, p. 3, Fig. 12). Morga nucodon modified from Kermack, Mussett, & Rigney (1981, Figs. 95, 99a; 1973, Fig. 7a); Allin (1975, p. 3, Fig. 11). Asioryctes modified from Carroll (1988, Fig. 20-3b). Abbreviations: ag = angular; ar = articular; cp = coronoid process; d = dentary; f = lateral temporal fenestra; j = jugal; mm = attachment site for mammalian jaw muscles; o = eye socket; po = post orbital; q = quadrate; rl = reflected lamina; sq = squamosal; ty = tympanic.

TAXONOMY
LATERAL TEMPORAL FENESTRA
LOWER JAW DENTARY
TEETH
LOWER JAW: POST- DENTARY BONES
MIDDLE EAR & JAW ARTICULATION
M: Early Placental mammals
Asioryctes
Upper Cretaceous
Merged with eye socket; cheek arch bowed out laterally 100% of jaw length is the den- tary; condylar process in contact with squamosal Fully differentiated teeth; incisors, canines, premolars; one tooth replacement No post-dentary bones 3 middle ear bones (stapes, incus, malleus) + tympanic; squamosal-dentary jaw joint
L: "Pantothere" mammals
Amphitherium
Middle/Upper Jurassic
X 100% of jaw length is the den-  tary; condylar process contacts squamosal Fully differentiated teeth; incisors, canines, premolars; one tooth replacement Post-dentary bones migrated to middle ear Probably 3 middle ear bones (stapes, incus, malleus) + tympanic; squamosal-dentary jaw joint
K: Morganucodontid mammals
Morganucodon  Upper Triassic & Lower Jurassic
Merged with eye socket; cheeck arch bowed out laterally 100% of jaw length is the den- tary; condylar process expanded posteriorly to make contact with squamosal Fully differentiated teeth; incisors, canines, premolars; one tooth replacement 20% of jaw length; reflected lamina decreased to narrow ribbon-like horseshoe Stapes extends from inner ear capsule to quadrate; quadrate tiny; both quadrate-articular and squamosal-dentary jaw joints
J: Chiniquodontid cynodonts
Probainognathus
Middle Triassic
Much larger than eye socket; 40- 45% of skull length; expanded posterioirly, medially, & laterally; midline of skull narrow sagittal crest; chek arch bowed out laterally 95% of jaw length is the dentary; large coronoid process expanded posteriorly; condylar process expanded posteriorly Large single canine; cheek teeth multicusped; tooth replacement reduced 20% of jaw length; angular notch widened ventrally; width of main part of angular decreased; reflec - ted lamina decreased to narrow ribbon-like horseshoe Stapes extends from inner ear capsule to quadrate; quadrate tiny; quadrate-articular joint
I:Galesaurid cynodonts
Thrinaxodon
Lower Triassic
Much larger than eye socket; 40% of skull length; expanded pos- terioirly, medially, & laterally; midline of skull narrow sagittal crest; chek arch bowed out laterally 85% of jaw length is the dentary; large coronoid process expanded to top of eye socket and pos- teriorly; jaw muscles attached to most of coronoid process Large single canine; cheek teeth multicusped; tooth replacement reduced 25% of jaw length; angular notch widened ventrally; width of reflec- ted lamina decreased; width of main part of angular decreased Stapes extends from inner ear capsule to quadrate; quadrate small; quadrate-articular jaw joint
H: Procynosuchid cynodonts
Procynosuchus
upper Upper Permian
Much larger than eye socket; 40% of skull length; expanded pos- terioirly, medially, & laterally; midline of skull narrow sagittal crest; chek arch bowed out laterally 75-80% of jaw length is the den- tary; coronoid process expanded to near top of eye socket and posteriorly; jaw muscles  attached to dorsal part of coronoid process Large single canine; cheek teeth multicusped 30% of jaw length; angular notch widened ventrally; width of reflected lamina decreased Stapes extends from inner ear capsule to quadrate; quadrate small; quadrate-articular jaw joint
G: Early Therocephalians
Pristerognathus
lower Upper Permian
Larger than eye socket; expanded posteriorly and medially; 30% of skull length 75-80% of jaw length is the den- tary; posterior end of dentary expanded posteriorly and dorsally into narrow blade-like coronoid process; rises to middle of eye socket Large single canine; other teeth simple cones. 35% of jaw length; angular notch deepened into a cleft; reflected lamina large, broad, blade-like Stapes extends from inner ear capsule to quadrate; quadrate small; quadrate-articular jaw joint
F: Early Gorgonopsians
Eoarctops
lower Upper Permian
Slightly larger than eye socket; expanded posteriorly and medially (minimal); 20-25% of skull length 65-75% of jaw length is the den- tary; posterior end of dentary slightly expanded posteriorly and dorsally as incipient coronoid process Large single canine; other teeth simple cones. 40% of jaw length; angular notch deepened into a cleft; reflected lamina large, broad, blade-like Stapes extends from inner ear capsule to quadrate; quadrate- articular jaw joint
E: Eotitanosuchians
Sphenacodon
Lower Permian
Small; slightly smaller than eye socket; slightly expanded posteriorly and medially 65-75% of jaw length is the den- tary; posterodorsal edge rises broadly but slightly above tooth row Large single canine; other teeth simple cones. 40% of jaw length; angular notch deepened into a cleft; reflected lamina large, broad, blade-like Stapes extends from inner ear capsule to quadrate;  quadrate- articular jaw joint 
D: Late sphenacodonts
Sphenacodon
Upper Pennsylvanian
Small; smaller than eye socket; confined to one side of skull 65% of jaw length is the dentary; posterodorsal edge rises broadly but slightly above the tooth row Enlarged incipient canines; other teeth simple cones 60% of jaw length; venntral edge of angular notched ("angular notch") offsetting a short pro- tusion (reflected lamina) Stapes extends from inner ear capsule to quadrate; quadrate large and plate-like; quadrate- articular jaw joint
C: Early spenacodonts
Haptodus
Upper Pennsylvanian
Tiny; smaller than eye socket; confined to one side of skull 65-75% of jaw length is the den- tary; posterodorsal edge rises broadly but slightly above tooth row Undifferentiated; slightly enlarged incipient canines just behind nares 70% of jaw length; ventral edge of angular with shallow indentation Stapes extends from inner ear capsule to quadrate; quadrate- articular jaw joint
B: Early ophiacodonts
Archaothyris
upper Middle Pennsylvanian
Tiny; smaller than eye socket; confined to one side of skull x Undifferentiated; slightly enlarged incipient canines just behind nares x Stapes extends from inner ear capsule to quadrate; quadrate- articular jaw joint
A: Protorothyrids
Hylonomus
lower Middle Pennsylvanian
Absent 65-75% of jaw length is the den- tary; posterodorsal edge rises broadly but slightly above tooth row Undifferentiated; slightly enlarged incipient canines just behind nares 70% of jaw length; ventral edge of angular continuous  Stapes extends from inner ear capsule to quadrate; quadrate- articular jaw joint

Table 1: Morphology of synapsid reptiles and mammals (Note that Hylonomus is a protothyrid, not a synapsid). Data from references cited in text.

Modern reptiles and mammals are very distinctive, easily diagnosable, and do not intergrade. Reptiles are covered by scales, mammals by hair; reptiles are cold-blooded, mammals warm-blooded; reptiles do not suckle their young, mammals have mammary glands; reptiles have sprawling posture, mammals have upright posture. Most of these features are soft part anatomy or physiology that very rarely fossilize (although dinosaur skin impressions are known from Cretaceous sediments, and imprints of mammal hair are known from Eocene bats from Germany; Franzen, 1990). In the fossil record, we must look to skeletal features.

There are many skeletal features which allow us to distinguish the reptiles from the mammals (Carroll, 1988; Table 1, rows A, M). The single most important defining characteristic is the nature of the articulation of the lower jaw to the skull (Simpson, 1959). In reptiles, multiple bones comprise the lower jaw. A small bone at the posterior end of the lower jaw, the articular, articulates with the quadrate bone of the skull (Simpson, 1959; Carroll, 1988). In mammals, one large bone, the dentary, comprises the lower jaw. It articulates with the squamosal bone of the skull (Simpson, 1959; Carroll, 1988).

From comparative anatomy studies, it is certain that most of the bones of the reptiles and mammals are homologous (Crompton & Parker, 1978; Carroll, 1988). Of greatest importance, the middle ear bones of mammals (stapes, incus, malleus, and tympanic) are homologous with several of the skull and jaw bones of reptiles (stapes, quadrate, articular, and angular, respectively; Romer, 1956, p. 33-38, 1970a; Allin, 1975, 1986; Allin & Hopson, 1992; Crompton & Parker, 1978; Hopso n, 1987, 1994; Carroll, 1988). One group of reptiles, the synapsids (Subclass Synapsida), share with the mammals an additional homologous structure: the lateral temporal fenestra, which is an opening in the skull behind the eye socket at the triple junction between the squamosal, jugal , and post orbital bones (Broom, 1932; Frazetta, 1968; Kemp, 1982; Carroll, 1988). A band of bone composed of the jugal and the squamosal is adjacent to the lateral temporal fenestra (Broom, 1932; Kemp, 1982; Carroll, 1988). This is the cheek arch so characteristic of mammal skulls (Broom, 1932; Kemp, 1982; Carroll, 1988). Therefore, synapsids are commonly named the “mammal-like reptiles.”

The presence of diagnosable morphologic differences between reptiles (including the oldest reptiles and the oldest synapsids) and mammals distinguishes them as distinct taxa. This allows us to test evolution by looking for transitional forms between the two. Because many of the bones are homologous, we should find evidence illustrating how these bones were modified over time to become the new bones. Furthermore, these morphologic changes should happen in parallel and in geochronologic succession.

Synapsid reptiles inhabited Pangea from the Middle Pennsylvanian through the Early Jurassic (Kemp, 1982, 1985; Sloan, 1983; Carroll, 1988; Hopson, 1969, 1987, 1994; Hopson & Crompton, 1969; Hotton, et al., 1986; Crompton & Jenkins, 1973; Sidor & Hopson, 1998; Romer & Price, 1940; Broom, 1932; Boonstra, 1963, 1969, 1971; Tchudinov, 1983; Olson, 1944; Tatarinov, 1974; Vyushkov, 1955; Efremov, 1954). From the Early Permian through the Early Triassic, they were the largest and most abundant land animals (Sloan, 1983; Colbert, 1965). Though much less well known to the general public than dinosaurs, one of the “cereal box dinosaurs,” Dimetrodon (the sail-backed reptile), is a synapsid, not a dinosaur (Romer & Price, 1940; Carroll, 1988). The oldest mammals are Late Triassic (Kemp, 1982; Carroll, 1988). Below is a discussion of the geochronologic succession linking synapsids and mammals. The oldest reptiles (named protorothyrids; Carroll, 1964, 1988, p. 192-199) are from the lower Middle Pennsylvanian, and the oldest synapsids (Reisz, 1972) are from the upper Middle Pennsylvanian, both of Nova Scotia. Upper Pennsylvanian and Lower Permian forms are known primarily from the midcontinent and Permian Basin region of the United States (Romer & Price, 1940; Currie, 1977, 1979; Kemp, 1982; Sloan, 1983). The basal Upper Permian forms are known from Russia (Tchudinov, 1960, 1983; Efremov, 1954; Olson, 1962; Sigogneau & Tchudinov, 1972; Ivakhnenko et al., 1997). Most of the Upper Permian and Lower Triassic succession is known from southern Africa, especially the Great Karoo of South Africa (Broom, 1932; Boonstra, 1963, 1969, 1971; Hopson & Kitching, 1972; Kemp, 1982; Sloan, 1983). The Middle Triassic forms are from South America (Romer, 1969a, 1969b, 1970b, 1973; Romer & Lewis, 1973; Bonaparte & Barbarena, 1975), and the Upper Triassic and Lower Jurassic mammals are known from Eurasia (Kermack, Mussett, & Rigney, 1973, 1981; Kemp, 1982). Subsequent Mesozoic mammals are known from all over the world (Simpson, 1928; Lillegraven et al., 1979).

When placed in proper geochronologic succession, the synapsids naturally form a succession of taxa (genera and families) that progressively become more mammal-like and less reptile-like (Kemp, 1982, 1985; Sloan, 1983; Sidor & Hopson, 1998; Hopson, 1987, 1994). Morphologic changes, summarized in Table 1 and Figure 1, affect the entire skeletal anatomy of these animals, but are most clearly displayed in their skulls.

The lateral temporal fenestra increased in size from a tiny opening smaller than the eye socket to a giant opening occupying nearly half the length of the skull. Ultimately, it merged with the eye socket, thus producing the full development of the cheek arch so characteristic of mammals (Broom, 1932; Frazetta, 1968; Kemp, 1982; Sloan, 1983; Hopson, 1987, 1994; Carroll, 1988).

Successively, the relative proportion of the lower jaw comprised of the dentary bone (teeth-bearing bone) gradually increased until the entire lower jaw consisted of the dentary (Kemp, 1982; Sloan, 1983; Carroll, 1988; Hopson, 1987, 1994). In Pennsylvanian and Lower and basal Upper Permian synapsids, the postero-dorsal edge of the lower jaw rose broadly but only slightly above the level of the tooth row (Romer & Price, 1940; Currie, 1977, 1979; Ivakhnenko et al., 1997; Tchudinov, 1960, 1983; Efremov, 1954; Olson, 1962; Sigogneau & Tchudinov, 1972; Hopson, 1987, 1994). In succeeding forms, the posterior part of the dentary expanded dorsally and posteriorly as a blade-like process, and progressively became larger (Broom, 1932; Boonstra, 1963, 1969, 1971; Sigogneau, 1970; Brink, 1963; Kemp, 1979; Hopson, 1987, 1994), forming the coronoid process (Parrington, 1946; Fourie, 1974; Romer, 1969b, 1970b, 1973; Hopson, 1987, 1994) to which the mammalian-type jaw musculature is attached (Barghusen, 1968; Bramble, 1978; Crompton, 1972; Crompton & Parker, 1978; Kemp, 1982; Sloan, 1983; Carroll, 1988). Concomitantly, the post-dentary bones progressively reduced in size (Allin, 1975; Crompton, 1972; Crompton & Parker, 1978; Kemp, 1982; Sloan, 1983; Carroll, 1988; Hopson, 1987, 1994).

Beginning with the Upper Pennsylvanian sphenacodonts, a notch developed in the angular bone that offsets a projection, the reflected lamina (Allin, 1975; Allin & Hopson, 1992; Hopson, 1987, 1994; Romer & Price, 1940; Currie, 1977, 1979; Kemp, 1982; Sloan, 1983; Carroll, 1988). The reflected lamina first became a large blade-like flange (Allin, 1975; Allin & Hopson, 1992; Hopson, 1987, 1994; Ivakhnenko et al., 1997; Tchudinov, 1960, 1983; Efremov, 1954; Olson, 1962; Sigogneau & Tchudinov, 1972; Broom, 1932; Sigogneau, 1970; Boonstra, 1963, 1969, 1971), and then was progressively reduced to a delicate horseshoe-shaped bone (Allin, 1975; Allin & Hopson, 1992; Hopson, 1987, 1994; Brink, 1963; Parrington, 1946; Fourie, 1974; Romer, 1969b, 1970b, 1973; Kermack, Mussett, & Rigney, 1973, 1981; Kemp, 1979, 1982; Sloan, 1983; Carroll, 1988).

Simultaneously, the quadrate progressively decreased in size (Allin, 1975; Allin & Hopson, 1992; Hopson, 1987, 1994; Kemp, 1982; Sloan, 1983; Carroll, 1988). The articular did not decrease in size much, being small initially, but developed a downward-pointing prong (Allin, 1975; Allin & Hopson, 1992; Hopson, 1987, 1994; Kemp, 1982; Sloan, 1983; Carroll, 1988). In the synapsids, the lower jaw was hinged to the skull by the articular and quadrate bones (Crompton, 1972; Crompton & Parker, 1978; Allin, 1975; Allin & Hopson, 1992; Hopson, 1987, 1994). Thus they are classified as reptiles (Simpson, 1959; Kemp, 1982; Sloan, 1983; Carroll, 1988). As the quadrate and articular became smaller, they were relieved of their solid suture to the dentary and skull (Crompton, 1972; Allin, 1975, 1986; Allin & Hopson, 1992; Hopson, 1987, 1994; Crompton & Parker, 1978; Kemp, 1982; Sloan, 1983; Carroll, 1988). A projection of the dentary extended posteriorly and made contact with the squamosal. Morganucodon possessed the mammalian dentary-squamosal jaw joint adjacent to the reptilian articular-quadrate jaw joint (Kermack, Mussett, & Rigney, 1973, 1981; Carroll, 1988). It is classified as the first mammal, but it is a perfect intermediate. Now that a new jaw joint was established, the quadrate and articular were subsequently relieved of that function (Crompton, 1972; Allin, 1975, 1986; Allin & Hopson, 1992; Hopson, 1987, 1994; Crompton & Parker, 1978; Kemp, 1982; Sloan, 1983; Carroll, 1988). Ultimately, in Middle and Upper Jurassic mammals, the tiny quadrate, articular, and ring-like angular migrated as a unit to the middle ear where they joined the stapes and became the incus, malleus, and tympanic bones (Allin, 197 5, 1986; Allin & Hopson, 1992; Hopson, 1987, 1994; Kemp, 1982; Sloan, 1983; Carroll, 1988).

Progressively, the teeth became differentiated. The large canines developed first, followed by the development of multicusped cheek teeth, reduced tooth replacement (Osborn & Crompton, 1973; Crompton & Parker, 1978), and finally full y differentiated incisors, canines, premolars, and molars with one tooth replacement during life (Kemp, 1982; Hopson, 1994).

Many other morphologic changes are documented in the fossil record. These demonstrate the morphologic and geochronologic succession from sprawling limb posture to upright limb posture of mammals (Jenkins, 1971; Romer & Lewis, 197 3; Kemp, 1982; Carroll, 1988; Hopson, 1994). As Jenkins (1971, p. 210) stated, “In details of morphology and function, the cynodont post-cranial skeleton should be regarded as neither ‘reptilian’ nor ‘mammalian’ but as transitional between the two classes .” Other changes have been adequately summarized elsewhere (Kemp, 1982; Sloan, 1983; Carroll, 1988; Hopson, 1994). Obviously, fundamental physiologic changes must have taken place as well, many of which are not directly preserved in the fossil record, though some can be inferred from the skeletal anatomy (Findlay, 1968; Kemp, 1982; Sloan, 1983, Carroll, 1988; Hopson, 1994).

This is well documented in the fossil record by a massive volume of incontrovertible data that cannot be explained away. Such large-scale, progressive, continuous, gradual, and geochronologically successive morphologic change (Sidor & Hopson, 1998) is descent with modification, and provides compelling evidence for evolution on a grand scale.

(The above is from The Fossil Record: Evolution or "Scientific Creation", which is yet ANOTHER link I had already posted to this thread, which "7MMmag" didn't think he needed to read before trying to ridicule this topic...)

Those fossils and transitions are also on scores of webpages which anyone can find if they just bother to Google for "reptile mammal transition", but you didn't even bother to check your presumptions before you posted, because you already *knew* everything you needed to know about evolution and the fossil evidence, right?

So I'm sorry, what was that you were saying about how *I* must not have known what I was talking about when I wrote:

"The change occurred *gradually*, across *many* generations, from a very "lizardlike" form, eventually to a "lizardish with vaguely mammalian features" form, to eventually something that people might consider "mostly mammal",
...and which you ridiculed because, after all, you say, "The proofs are thin, if that (non-extant,is more like it!)"....

So would you care to revise your horsecrap now, and retract your childish behavior?

Which of course, leads us right back to where we started.

Yup -- we started with you demonstrating how ignorant and obnoxious and foolish you were. And we're still there.

I guess you can't see it.

I see it just *fine*, son. You're the one who smugly declares the non-existence of things which are well known to millions of science-literate people...

I regret to inform you that you have come unarmed to a battle of wits and knowledge.

Too brainwashed....

No, I'm just too knowledgeable. And sober.

But hey, I'm sure you'll want a rematch, so here's your chance. Just play (cue theme music) "The Anti-Evolution Game!"

Courtesy of http://www.holysmoke.org/:

The Anti-Evolution Game

by Dr Pepper

Here's an opportunity to see how good you are at refuting evolution scientifically. That means using science, not faith. If you have faith that evolution is false, that's great for you but has nothing to do with science.

HOW TO PLAY

Just write a series of statements showing either inadequacy in the basic tenets of evolution, or contradictory evidence.

It is not necessary to absolutely disprove evolution, just give us something to rock conventional science.

Your statements will be evaluated and assigned points. 10 points wins.

PROCEDURE

1. To enter the game, leave a post declaring your intention to play. You may start making statements in that post if you like.

2. You will then have 60 days to make as many posts as you like with statements for the game. If you do not make 10 points in those 60 days you will have to start over.

3. All posts in the game should have ANTI-EVOLUTION GAME as the subject line and contain only statements relevant to the game. Anything else will not be counted.

WINNING

I'm self (un)employed so i can't give away cadillacs or trips to Hawaii. But if you can get 10 points your name will go on a public list of succesful challengers of evolution, a list that is currently empty. And i will send a $10 donation to the organization of your choice.

SCORING

                 Type of Statement                            Points

Observation of spontaneous generation of a modern lifeform
either from nothing or from nonliving elements.                  5

Explanation of how totally independent dating methods agree
so well if the dates they show are wrong.                        5

Evidence showing that all remains of Earth are younger than
1 million years.                                                 3

Example of total genetic discontinuity (polymerase chain
reaction) between two species considered closely related
by conventional science.                                         2

Example of two species considered separated by over 100
million years of time by conventional science found to           2
be contemporaneous.

Example of a fossil considered over 2 million years old by
conventional science showing the exact same genetic makeup as
a modern member of the same species.                             1

Correct statement of the theory of evolution.                    1

Any other single statement showing you understand evolution.     1

Any quote from secondary sources.                               -1

Any statement mischaracterizing evolution.                      -1

Misunderstanding of the difference between theory and fact.     -2

Misunderstanding of the 2nd Law of Thermodynamics.              -2

Misunderstanding of entropy, order, randomness or
complexity.                                                     -2

Misunderstanding of the use of C-14 dating.                     -2

Misunderstanding of isochron dating.                            -2

Misunderstanding of nuclear decay.                              -2

Misunderstanding of the speed of light.                         -2

Appeal to supernatural entities. Such is outside the
framework of science.                                           -2

Misquoting or distorting someone's statement.                   -3

Mischaracterizing a disagreement on the hows of evolution
as doubt of the fact of evolution.                              -4

Appeal to your own ignorance "I don't see how else..."
is a description of your personal inadequacy, not that
of conventional science.                                        -4

Outright lie. It doesn't matter if you didn't know it
was a lie.                                                      -5

Use of argument already thoroughly refuted. You are
responsible for looking these things up.                        -5

Appeal to moral consequences. That has no bearing on
truth value.                                                    -5


Good luck! Come back around *any* time!
673 posted on 02/02/2005 3:53:49 AM PST by Ichneumon
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