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Author Topic:   Mammalian Middle Ear Evolution
AlphaOmegakid
Member (Idle past 2876 days)
Posts: 564
From: The city of God
Joined: 06-25-2008


Message 1 of 25 (484636)
09-30-2008 9:37 AM


The definitive mammalian middle ear (DDME) is an amazing organization of bones and soft tissue that give mammals the ability to hear in the broad frequency range that they can. The mammalian ear is substantially different than the reptilian ear from which we supposedly evolved.
So there must have been changes along the way. This is a well documented evolutionary story from the fossil record.... DDME
Modern Mammals all have the DDME. My question is according to the DDME theory above, when did the DDME actually evolve according to the theory. In other words, when did the ossicles separate and form the three bones in the DMME. If I understand correctly, it must have been sometime after Yanoconodon. Is this correct?
Edited by AdminNosy, : changed title

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AdminNosy
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Posts: 4754
From: Vancouver, BC, Canada
Joined: 11-11-2003


Message 2 of 25 (484639)
09-30-2008 9:52 AM


Title Change
Thread moved here from the Proposed New Topics forum.
ABE
I took the liberty of changing the title so it is easier for interested parties to spot on a topic list. I hope that is ok with you.
Edited by AdminNosy, : No reason given.

  
Wounded King
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Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 3 of 25 (484642)
09-30-2008 11:37 AM
Reply to: Message 1 by AlphaOmegakid
09-30-2008 9:37 AM


If I understand correctly, it must have been sometime after Yanoconodon. Is this correct?
Not necessarily. A primitive characteristic can survive in some lineages while the derived characteristic develops in others. So Yanoconodon's middle ear may be a morphological intermediate between modern mammals and other mammaliaforms but it doesn't necessarily put Yanoconodon in any sort of direct lineage from ancestral to modern mammals. Yanoconodon may have simply been part of a lineage where the intermediate form of middle ear persisted while the modern mammalian middle ear evolved in a parallel lineage. Therefore the timing of the evolution of the DMME is not given any sort of lower bound by Yanoconodon.
The Nature paper describing this discovery by Luo et al. (2007) suggests that this may be a retained feature from the common ancestor of monotremes, eutriconodonts and therians rather than that Yanoconodon is itself some sort of ancestral form and the detachment evolved separately in monotremes and therians. Alternatively the ancestral feature may have re-occurred in Yanoconodon.
The only timing we can state at all definitively is an upper bound for when a particular feature appears for the first time in the fossil record, this can only really be a guide to when it actually evolved.
As a further instance, many people will present extant modern species as possessing intermediate forms of optical sensory organs along the progression from rudimentary light sensing patches to a vertebrate like compound eye, this doesn't suggest any of these extant modern organisms are in any direct evolutionary lineage leading to modern vertebrates.
TTFN,
WK
Edited by Wounded King, : corrected some typing errors

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AlphaOmegakid
Member (Idle past 2876 days)
Posts: 564
From: The city of God
Joined: 06-25-2008


Message 4 of 25 (484647)
09-30-2008 1:57 PM
Reply to: Message 3 by Wounded King
09-30-2008 11:37 AM


The only timing we can state at all definitively is an upper bound for when a particular feature appears for the first time in the fossil record, this can only really be a guide to when it actually evolved.
Yes, I understand the homoplasy and convergent evolution. So what is the upper bound when the DMME shows in the fossil record? If I understand correctly, Yanoconodon was about 125mya. And it was a "transitional before the DMME. The DDME is a characteristic of all "modern mammals". So from 70mya or so all or most mmamals have the DDME. Correct? So did it appear between 125 and 70 mya or would this be a prediction of ToE.

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NosyNed
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Posts: 8996
From: Canada
Joined: 04-04-2003


Message 5 of 25 (484655)
09-30-2008 3:36 PM
Reply to: Message 4 by AlphaOmegakid
09-30-2008 1:57 PM


Serious misunderstanding...
So did it appear between 125 and 70 mya or would this be a prediction of ToE.
This hints at a serious misunderstanding of concepts and terms.
"ToE" stands for the "theory of evolution". It is a scientific model of how the world works. It is an explanation of the facts (like the various stages of the MME). However, the exact timing is subject to many contingent variables so it isn't going to be very good at predicting a specific time frame.
The time frame is determined not by theory but by looking in the fossil record. The ToE may tell us what kind of patterns to expect but not the timing.
An analogy: I have a theory that explains how humans may get from one place to another. It clearly states that they don't (on their own) fly. It understands they are capable of picking good routes. To decide how long a human will take to get across a valley no amount of details about general human locomotion will help me. I have to know what the particular human is capable of, what the terrain is like and how motivated he/she is. In fact, to determine travel time I have to measure it not theorize about it.
Then if I find the human traveled in accordance with my theory it is confirmed to a small degree. She/he may take a few hours strolling across the valley or a couple of days. No problem. But if the human took only a half hour my theory has a serious problem. I didn't include cars and superhighways perhaps.
In a similar manner the fact that the nature of the MME was noted in relation to reptiles decades before Darwin and over a century later the fossil record matched that is a powerful confirmation for the theory. A serious mismatch would have been a problem like leaving cars out of my human locomotion theory.
But the MME evolution falling anywhere over a much bigger range than 125 to 70 Mya is still within expectations. Like a human taking days to cross the valley or only an afternoon.

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 Message 4 by AlphaOmegakid, posted 09-30-2008 1:57 PM AlphaOmegakid has replied

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AlphaOmegakid
Member (Idle past 2876 days)
Posts: 564
From: The city of God
Joined: 06-25-2008


Message 6 of 25 (484658)
09-30-2008 4:42 PM
Reply to: Message 5 by NosyNed
09-30-2008 3:36 PM


Re: Serious misunderstanding...
The time frame is determined not by theory but by looking in the fossil record. The ToE may tell us what kind of patterns to expect but not the timing.
I disagree. Certainly the time frame is determined by the fossil record, but ToE makes predictions about the transitionals in the fossil record. The theory is only as good as its predictions, Right?
According to the wiki article, and the Nature article the fossil record would be consistent with ToE. Right? That means the fossil record is in accordance with the theory.
That also means that there is a potential falsification about the prediction of ToE (not the whole theory)within the DDME development. For instance what if the DDME was found in the earliest mammals. This would be in conflict with the ToE, Right?
Therefore, I am trying to find out what the ToE predicts about the reptile mammalian fossil record regarding the DMME. Does ToE predict that the earliest mammal didn't have the DMME? We know modern mammals are defined somewhat after the dinosaur extinction roughly 70mya. We know Yanoconodon did not have DDME at 125mya. Base on what we know from the fossil record, what does ToE predict regarding the DDME? Or does ToE predict anything about the DDME.
In other words, predictions are made before the fossils are found. And of course the before mentioned literature is in agreement with the ToE prediction. The question is what if fossils are found out of sequence showing the DMME much earlier in the fossil record. Does this falsify the prediction (not the theory) and what if the earliest mammals had the DMME leaving no evolutionary story or time to evolve. That would be a potential falsification of the OoS part of ToE wouldn't it?

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PaulK
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Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


Message 7 of 25 (484660)
09-30-2008 5:02 PM
Reply to: Message 6 by AlphaOmegakid
09-30-2008 4:42 PM


Re: Serious misunderstanding...
quote:
That also means that there is a potential falsification about the prediction of ToE (not the whole theory)within the DDME development. For instance what if the DDME was found in the earliest mammals. This would be in conflict with the ToE, Right?
You're expecting to work out an awful lot without fossil evidence (or an adequate substitute).
The theory of evolution does not say that the mammalian middle ear evolved in mammals, rather than in their pre-mammalian ancestors - just feathers evolved in the dinosaurian ancestors of birds. In that case the DDME would be found in the very earliest mammals, as feathers are found on the earliest birds. The question is simply not resolvable on purely theoretical grounds.
A better potential falsification would be if there were no evolutionary route to the mammalian middle ear from any potential ancestors. As the article points out, that was once thought to be the case, but the discovery of intermediate forms proved otherwise.
And that is a very strong confirmation of evolution - if evolution were false there is no good reason why these intermediates should exist.

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 Message 6 by AlphaOmegakid, posted 09-30-2008 4:42 PM AlphaOmegakid has replied

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AlphaOmegakid
Member (Idle past 2876 days)
Posts: 564
From: The city of God
Joined: 06-25-2008


Message 8 of 25 (484663)
09-30-2008 5:36 PM
Reply to: Message 7 by PaulK
09-30-2008 5:02 PM


Re: Serious misunderstanding...
The theory of evolution does not say that the mammalian middle ear evolved in mammals, rather than in their pre-mammalian ancestors -
Unfortunately for you, this statement is patently false. Yanoconodon is an early mammal, and it doesn't have the DDME according to the Nature article. There are many others early mammal fossils, but DDME data is not available on all of them
All reptiles have the reptilian ear. Modern mammals have DDME. That only leaves the transitions to be in both reptiles and early mammals.
What I am trying to establish is does ToE actually make any predictions. Or does it just morph the theory to the data? ToE should be able based on the current level of substantial mammalian fossil record to predict roughly when the DMME arose. In physics there are many mathematical equations associated with theories. The math is not data, but it predicts certain data should exist. Then if the data is found that supports the prediction then the theory gains credibility. GR and BBT are great examples of this.
How about ToE? What does it predict about the DMME? If it predicts what has been found according to the citations, (which everone so far is agreeing that it predicted)then that means the the DMME should appear sometime after 125mya.

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 Message 7 by PaulK, posted 09-30-2008 5:02 PM PaulK has replied

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 Message 9 by PaulK, posted 09-30-2008 5:45 PM AlphaOmegakid has replied
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PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


Message 9 of 25 (484664)
09-30-2008 5:45 PM
Reply to: Message 8 by AlphaOmegakid
09-30-2008 5:36 PM


Re: Serious misunderstanding...
quote:
Unfortunately for you, this statement is patently false. Yanoconodon is an early mammal, and it doesn't have the DDME according to the Nature article. There are many others early mammal fossils, but DDME data is not available on all of them
ROTFL! You are seriously suggesting that a fossil is pure theory rather than fossil evidence ?!?
You prove my point. It is the fossil evidence that tells use where the DDME evolved NOT pure theory.
quote:
What I am trying to establish is does ToE actually make any predictions.
And, as I pointed out the article that you cited is all about a successful prediction, made from applying the theory to the evidence known at the time. And there are other, similar predictions, notably the discovery ofTiktaalik

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 Message 8 by AlphaOmegakid, posted 09-30-2008 5:36 PM AlphaOmegakid has replied

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NosyNed
Member
Posts: 8996
From: Canada
Joined: 04-04-2003


Message 10 of 25 (484665)
09-30-2008 6:00 PM
Reply to: Message 6 by AlphaOmegakid
09-30-2008 4:42 PM


Re: Serious misunderstanding...
For instance what if the DDME was found in the earliest mammals. This would be in conflict with the ToE, Right?
Why would that be in conflict?

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Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 11 of 25 (484668)
09-30-2008 6:20 PM
Reply to: Message 4 by AlphaOmegakid
09-30-2008 1:57 PM


So what is the upper bound when the DMME shows in the fossil record?
The first appearance of the DMME in the fossil record, it can have evolved no later than that, although obviously if we are talking about 2 separate lineages where the trait evolves independently then its a bit more complex.
The earliest know mammalian fossil with a DMME is, I think, Hadrocodium (Luo et al., 2007). Hadrocodium is dated at ~195 MYA, but even before then the earliest instance of the DMME was at ~150 MYA, still well before your Yanoconodon date of 125 MYA.
And it was a "transitional before the DMME
This is not supported from the original paper or from the Wikipedia article. In fact looking at the wikipedia article you lined to I have to ask if you even bothered to actually read it? It says right there in the wiki ...
Wikipedia writes:
In the lineage most closely related to mammals, the jaws of Hadrocodium (about 195M years ago in the very early Jurassic) suggest that it or a very close ancestor may have been the first to have a fully mammalian middle ear
So do you understand what a transitional fossil is yet? As I pointed out right at the start all it means is that it shows an intermediate morphology in terms of the middle ear between modern mammals and their early mammaliaform ancestors, not that it is itself necessarily an ancestral species to modern mammals.
Therefore we can have an 'intermediate fossil' appear in the fossil record well after the first instance of the trait it is an intermediate stage to.
To reiterate ... it was a transitional but for all we know it was extant after the DMME was already established in the mammalian lineage.
So from 70mya or so all or most mmamals have the DDME. Correct?
From considerably before that although related mammaliaforms, such as Yanoconodon, obviously still showed the transitional middle ear morphology at later times.
So did it appear between 125 and 70 mya or would this be a prediction of ToE.
No and no. What the evolutionary theory did predict was that such an intermediate form would exist. When it is actually found in the fossil record is relatively immaterial.
TTFN,
WK

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AlphaOmegakid
Member (Idle past 2876 days)
Posts: 564
From: The city of God
Joined: 06-25-2008


Message 12 of 25 (484670)
09-30-2008 6:28 PM
Reply to: Message 9 by PaulK
09-30-2008 5:45 PM


Re: Serious misunderstanding...
ROTFL! You are seriously suggesting that a fossil is pure theory rather than fossil evidence ?!?
Are you laughing at your own mistake. It is you who said that:
The theory of evolution does not say that the mammalian middle ear evolved in mammals, rather than in their pre-mammalian ancestors -
Did you not? You are mistaken. The ToE does not say that. Pre-mammalian ancestors are reptilian transitionals. There are mammals that do not have the DDME. The ToE does say that the DDME evolved partially in reptiles and then continued into mammals until it became what is known as the DMME in modern mammals.
You prove my point. It is the fossil evidence that tells use where the DDME evolved NOT pure theory.
Yes fossils are evidence. But the ToE predicts things that haven't been found. You used Tiktaalik as an example. Probably a fair example of a prediction before the find. That's how it should work. Now my question is what is the prediction of ToE about when the DDME ear evolved? If it can predict Tiktaalik, can't the theory predict the first DDME find? Isn't that the same principle? Would it predict J1,J2,J3,K1 or K2 for instance? That's the question.
Does ToE based on the fossil evidence of the ear and jaw predict that the DMME evolved sometime after 125mya, before 125mya, closer to 70mya, or pick any number. Based on the evidence that we currently have, what would or does the theory predict?

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NosyNed
Member
Posts: 8996
From: Canada
Joined: 04-04-2003


Message 13 of 25 (484674)
09-30-2008 6:57 PM
Reply to: Message 12 by AlphaOmegakid
09-30-2008 6:28 PM


Predictions
This is an obvious prediction of the ToE.
Well over a century ago it was noted that the ear bones develop like reptilian jaw bones.
The ToE says that if mammals were not around for all times then they developed from existing animals. When we look for likely candidates for mammals ancestors there isn't much choice but reptiles. In addition, the development pathways suggest that reptiles are a good candidate.
Therefore, we expect to find the various things which characterize the modern definition of what a mammal is in various stages of transitions. This we have found.
The ToE predicts that there will be transitional forms between what are currently end branches of the 'tree of life'. The early mammals, therapsids and reptiles before them are just such a chain of transitional forms.
As far as predicting the time frame it would be determined after dates are applied to know fossils NOT directly from theory. Then the theory can give a time frame to look in.
This is the case with Tiktalik. We had fish with some amphibian traits on one side of a 10 million year gap and amphibians with clear fish like traits on the other side of the gap. It isn't rocket science to figure out that somewhere in that 10 million years there should be something so transitional that we could no longer call it fish or amphibian (so the half joking -- fishaphibian). The theory then tells us where to look: where would selection act to push the path from fish to amphibian along? -- certainly not in deep oceans.
In the case of the MME we have fully developed mammals at one point in time. If there is going to be an evolutionary path to them (which the ToE predicts there will be) then the transitionals will be before the fully developed forms (duh!). Then just like the Tiktalik case we bracket the time from on the older end. These transitional forms would be after some of the precursors were already extant.
I think in the case of the MME evolution I don't think we had to focus so hard to find the transitionals.
The ToE does say that the DDME evolved partially in reptiles and then continued into mammals until it became what is known as the DMME in modern mammals.
This is correct, of course. If we define a mammal as a vertebrate animals with a particular ear construction then all of the development had to happen (but only by definition) in earlier pre-mammal forms. But that would be caught in a trap of thinking about things only from the current perspective. It is solved a bit by using the term as you have -- "modern mammals". The mammal vs non-mammal dividing line is over evolutionary time scales not so sharply defined.
It is similar in the Tiktalik case just as the ToE tells us. We had fish. We had funny fish with sort of legs. We had amphibiany like fish. We had fishaphibians that are so in between they are hard to put in either taxon. Then we had very fishy amphibians and less fishy amphibians. Once the lineages have gone on the independent ways for a few years (millions, 10's of millions) it is easy to draw taxonomic boundaries. It isn't so easy while the transitions are happening.
In the case of reptiles and mammals we used to call the therapsids "mammal like" reptiles. That term is now out of favour. I don't now why but maybe one reason is that we'd end up with (as we filled in more transitionals) with reptile like mammals. And, like in the semi facetious Tiktalik case above, all sorts of other "inbetween" forms. It seems the choice is to put something like a transitional taxon in between so we can put all the mammal like reptiles, very very mammal like reptiles, the reptimals, the very reptile like mammals etc into it. This appears to be the therapsids but I'm not an expert so I don't know.
Based on the evidence that we currently have, what would or does the theory predict?
It's too late. We have the fossils already. We know about when the transition was taking place. I think you want a Tiktalik like prediction that is done before the discovery. Like I said, that we would find the transitional forms was a strong prediction but when we would find them required some fossil record to fit them into.
What do you expect?

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RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 14 of 25 (484681)
09-30-2008 9:18 PM
Reply to: Message 6 by AlphaOmegakid
09-30-2008 4:42 PM


What is predicted by ToE
Hello AlphaOmegakid,
I disagree. Certainly the time frame is determined by the fossil record, but ToE makes predictions about the transitionals in the fossil record. The theory is only as good as its predictions, Right?
What the theory of evolution says is that mechanisms of evolution we see in the world today are sufficient to explain patterns of life in the past, and thus it predicts that we will find patterns consistent with evolutionary processes in the fossil record (and in the genetic record). This prediction is what is tested by the fossil and genetic record.
The theory predicts that populations will change over time, that there will be a succession of hereditary traits in the populations from generation to generation, as new mutations are added to the existing mix, and old ones are eliminated (natural selection or genetic drift).
The theory predicts that isolated populations will necessarily have different successions of hereditary traits because (a) they will have different sets of new mutations in each population and (b) they will be living in different ecologies, so natural selection will favor traits matched to the different ecologies rather than for conformity.
Thus the theory of evolution predicts that in any hereditary lineage there will be a transition from a set of hereditary traits at point {A}, to a different, though related, set of hereditary traits at point {C}, and that at any point {B} intermediate in time between {A} and {C} the organisms will have intermediate sets of traits: some will be shared with {A} and not {C} and some will be shared with {C} and not {A}, and that there will still be many (if not most) traits that are shared by {A}, {B} and {C}. Thus fossil {B} is a transitional fossil because it is an intermediate form along the hereditary path from {A} to {C}.
There is only a relative relationship to time (from generation to generation), there is no strict number of fixed mutations and selected new traits per year, decade, century. There is no metric for how much change has to happen either.
According to the wiki article, and the Nature article the fossil record would be consistent with ToE. Right? That means the fossil record is in accordance with the theory.
Well yes, but that is because the fossil record is the record of what actually occurred, and because, so far, the theory of evolution is capable of explaining it by everyday evolutionary processes. This demonstrates the validity of the theory: each fossil is a test of the theory, and no fossil in the billions found, has yet invalidated the theory.
That also means that there is a potential falsification about the prediction of ToE (not the whole theory)within the DDME development.
Yes. Finding a development that is not in earlier organisms and which does not have any possible morphological development from homologous features with ancestors.
For instance what if the DDME was found in the earliest mammals. This would be in conflict with the ToE, Right?
Therefore, I am trying to find out what the ToE predicts about the reptile mammalian fossil record regarding the DMME. Does ToE predict that the earliest mammal didn't have the DMME?
No. It is found in the earliest mammals because it is a feature that is used to define when the first mammals evolved (hair an mammary glands not fossilizing that well), one of the diagnostic features. The hereditary lineage of the transition from reptile jaw and ear to mammal jaw and ear goes through many intermediate stages, several including a double jointed jaw as part of the transition.
http://www.geocities.com/...naveral/Hangar/2437/therapsd.htm
Palaeos: Page not found
Even if you found a similar development in an earlier synapsid, that would not invalidate the branch of evolution leading through therapsid to mammaliforms to mammals: it would just be another branch, likely starting from a common ancestor with similar start along the lineage of transition from reptile to mammal.
We know modern mammals are defined somewhat after the dinosaur extinction roughly 70mya. We know Yanoconodon did not have DDME at 125mya. Base on what we know from the fossil record, what does ToE predict regarding the DDME? Or does ToE predict anything about the DDME.
Actually the last in the synapsid - therapsid - cynodont lineage of transition from reptile ear to mammal ear was roughly 240 Million to 200 Million years ago, to mammaliforms (note you can move up and down, and in and out in detail, on this cladogram by clicking on it):
quote:
The Late Triassic Epoch of the Triassic Period: 228 to 200 million years ago

The following is a condensed reminder of some of the many changes from basal synapsids to basal mammals. ...
1. Metabolic rate: transition to more or less full homeothermy inferred from geographic range, nocturnal habit, etc.
2. Temporal fossa: increase in size; confluence with orbit.
3. Zygomatic Arch: development; replacement of jaw adductor by masseter as principal jaw muscle; greatly increased capacity for oral processing of food.
4. Lower jaw: dentary becomes only significant element of mandible; development of coronoid process; reduction of post-dentary elements; reflected lamina of angular; dentary-squamosal jaw articulation. See infra, ear.
5. Dentition: development of heterodont dentition with incisors, canines, pre-molars and molars; "permanent" (diphyodont) teeth with prismatic enamel; increasingly fixed pattern of occlusion; definite dental formula.
6. Palate: full secondary palate.
7. Ear: reflected lamina of the angular (tympanic); retroarticular process of articular; conversion of post-dentary bones to sensory use in middle ear. Reflected lamina may have been resonating chamber, followed by development of tympanic membrane framed by increasingly small and gracile reflected lamina and/or retroarticular process
8. Pineal foramen: pineal foramen initially becomes more conspicuous, then recedes and is lost.
9. Skull table: development of parietal crest with muscular attachment on outside of dermal bones.
10. Braincase: parietal and squamosal spread downward to cover braincase, gradually replacing (in advanced mammals) neurocranium while providing muscle attachment on lateral (formerly dorsal) surface; epipterygoid changes from pillar supporting parietal and braincase to alisphenoid element of skull, continuous with parietal, squamosal, & petrosal (fused otic capsule). Brain size does not increase relative to diapsids.
11. Skull fusions: fusion of parietals and frontals, otic capsule, occipitals, numerous other elements in therians; loss of dermal bones, e.g. post-orbitals.
12. Skull attachment: double occipital condyle, condyles move ventrally, development of mammalian circular form.
13. Spine: loss of lumbar ribs (reversed in advanced cynodonts & lost again in Mammalia); increase in number of sacral vertebrae (??); reduction of tail; vertebral articulations changed to accommodate dorsoventral undulation; vertebrae amphiplatyan (flat on both ends), implying loss of notochord remnants (?).
14. Limb girdles: reduction (e.g. pubes, coracoids) or loss of ventral elements; more vertical orientation of limbs.
15. Limbs: more vertical orientation; elongation of humerus & femur; digits shorter; calcaneal heel
16. Integument: fur?; mammalian muzzle
17. Habit: primitively large carnivores; great reduction in size; development of omnivorous and herbivorous adaptations. --ATW 001202
Those are the "diagnostic traits" of mammals, and it includes the ear.
After that we find fossils of small shrew-like mammals that take us up to 70kyrs ago and the great meteor catastrophe\opportunity (its a matter of POV eh?).
In other words, predictions are made before the fossils are found.
That fossils found would be intermediate in form between ancestors and descendants.
The question is what if fossils are found out of sequence showing the DMME much earlier in the fossil record.
Think of your sister getting her wisdom teeth in much sooner than you do, even though you are older -- does this out of sequence formation invalidate your existence or heredity from your parents?
Enjoy.
Edited by RAZD, : million not thousand, added map

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
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This message is a reply to:
 Message 6 by AlphaOmegakid, posted 09-30-2008 4:42 PM AlphaOmegakid has not replied

Replies to this message:
 Message 15 by NosyNed, posted 09-30-2008 10:03 PM RAZD has replied
 Message 22 by Wounded King, posted 10-01-2008 7:36 AM RAZD has replied

  
NosyNed
Member
Posts: 8996
From: Canada
Joined: 04-04-2003


Message 15 of 25 (484685)
09-30-2008 10:03 PM
Reply to: Message 14 by RAZD
09-30-2008 9:18 PM


Re: What is predicted by ToE
240,000
?

This message is a reply to:
 Message 14 by RAZD, posted 09-30-2008 9:18 PM RAZD has replied

Replies to this message:
 Message 16 by RAZD, posted 10-01-2008 12:46 AM NosyNed has not replied

  
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