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Fossil Discovery Is Heralded


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#41 CTD

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Posted 22 May 2009 - 03:41 AM

Darwin, contrary to popular opinion, is not a prophet for evolutionists and he did, in fact, get a few things wrong.

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The trouble with cryptotheism is: it's mighty hard to secretly establish consensus.

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#42 jason78

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Posted 22 May 2009 - 03:52 AM

The trouble with cryptotheism is: it's mighty hard to secretly establish consensus.

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There were a lot of interesting comments in that thread. Thanks for the link.

#43 de_skudd

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Posted 22 May 2009 - 08:52 AM

Darwin, contrary to popular opinion, is not a prophet for evolutionists and he did, in fact, get a few things wrong.

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A “few” things? The title of the book (in its entirety) is enough to cast dispersion on the model, let alone its contents.

#44 Bruce V.

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Posted 22 May 2009 - 09:54 AM

Google "The Modern Synthesis" for the most comprehensive explanations of current evolutionary theory.


Modern  Synthesis

Does this describe Modern synthesis correctly in your opinion?

This is an interesting article about the subject: Modern Sythesis tested.

If you want we could discuss this article more.

Genetic drift is very interesting conceptually. However, if almost all mutations are negative the genetic drift would be downward not upward.

Current fossil evidence strongly supports Evolution, even if there are arguments about the rate and periodicy of speciation events.



Would you unpack that statement for me please. Just stating something is a fact or proven doesn't make it so.

Also, 'increasing complexity' is a misconception. Evolution does not predict increases in complexity, just diversity.


Natural selection produces fixation not diversity.

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Posted 22 May 2009 - 11:40 AM

Modern  Synthesis

Does this describe Modern synthesis correctly in your opinion?

This is an interesting article about the subject:  Modern Sythesis tested.

If you want we could discuss this article more. 


TalkOrigins does provide good overviews of evolutionary theory and its related concepts, though they don't update their information all that often and some of their reference material can be a couple of decades old.

I am afraid I don't have the background to be able to properly discuss the article you linked, though I will give it a read.

Would you unpack that statement for me please.  Just stating something is a fact or proven doesn't make it so.


Absolutely. Observations of the fossil record indicate the following: That life changes over time, that these changes follow an observable trend, and that the trend is that life forms give rise to similar, but slightly modified forms.

This is something that many creationists will agree with, though they will insist that all variation occurs "within kind" and that the time-scale is different.

Natural selection produces fixation not diversity.

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Natural Selection produces fixation within a species when selection pressures remain constant. In a dynamic system, one would expect fluctuating pressures to produce many different types of species. One does not necessarily expect that some species will be more complex than others.

#46 de_skudd

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Posted 22 May 2009 - 12:34 PM

The trouble with cryptotheism is: it's mighty hard to secretly establish consensus.

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I disagree CTD, there are crypto-theists in here right now displaying their faith, and denying it at the same time! :)

#47 Bruce V.

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Posted 22 May 2009 - 12:43 PM

Overture,May 22 2009, 11:40 AM

TalkOrigins does provide good overviews of evolutionary theory and its related concepts, though they don't update their information all that often and some of their reference material can be a couple of decades old.

I am afraid I don't have the background to be able to properly discuss the article you linked, though I will give it a read.




I did a google search on modern synthesis and that it isn't discussed much. Even sites like Answer in Genesis and other creation sites only make minor reference to the theory. It seams it doesn't have many backers other than talk origins.

But these 2 articles destroy the theory IMO.

link 1

link 2

[quote name='Overture' date='May 22 2009, 11:40 AM']

absolutely. Observations of the fossil record indicate the following: That life changes over time, that these changes follow an observable trend, and that the trend is that life forms give rise to similar, but slightly modified forms.


I asked the question hoping to learn something from your side. I really want to listen. So I am opening a door for you to prove that statement. I will try and just listen if is a legitimate post to educate rather than pontificate.

QUOTE=Overture,May 22 2009, 11:40 AM

This is something that many creationists will agree with, though they will insist that all variation occurs "within kind" and that the time-scale is different.
Natural Selection produces fixation within a species when selection pressures remain constant. In a dynamic system, one would expect fluctuating pressures to produce many different types of species.




That is really nice story. But making monkey/ape/human population even smaller by separating a small population and adding pressure makes evolution even more difficult for me to fathom. Until recently the human population was at most only about 1 million people in a given year. That is a very very small population. Monkeys and apes do not have large populations either historically.

OTOH Lenski has a huge population of e-coli and dwarfs all the population of all the mammals that has been on the earth combined. He adds selective pressure and isolates mutations and selectively grows them. He puts a lot of intelligence into his lab and yet the e-coli are still e-coli. His citric acid mutation is interesting but the e-coli has only 3 beneficial mutations. Nothing like the ape to man morphological changes which occurred supposedly on a much much smaller population.

[quote name='Overture' date='May 22 2009, 11:40 AM']
One does not necessarily expect that some species will be more complex than others.


The whole point of evolution theory is to prove how complexity occurred in life IMO.

#48 CTD

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Posted 22 May 2009 - 12:44 PM

I disagree CTD, there are crypto-theists in here right now displaying their faith, and denying it at the same time!  :)

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Absolutely! But beyond that, there's not a lot of agreement. Support some form of evolutionism, but which form? Acknowledge which gods, and which versions? Some simply worship themselves & assume their own assertions dictate reality; others pick and choose from the abundant cryptopantheon.

Ignorance plays a role also, as does the authority of the cryptopriesthood. How many even realize they need the Öort god?

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Posted 22 May 2009 - 12:55 PM

I asked the question hoping to learn something from your side.  I really want to listen.  So I am opening a door for you to prove that statement.  I will try and just listen if is a legitimate post to educate rather than pontificate.


Do you disagree that this is what is observed in the fossil record? I could cut/paste articles and provide links if you want, but from the articles you've linked I imagine that you're pretty familiar with scientific literature.

That is really nice story.  But making monkey/ape/human population even smaller by separating a small population and adding pressure makes evolution even more difficult for me to fathom.  Until recently the human population was at most only about 1 million people in a given year.  That is a very very small population.  Monkeys and apes do not have large populations either historically. 


1 million is not actually a small population at all. It is in fact an extremely large population for a creature as large as a human. There is no absolute answer for numbers needed to guarantee the continued survival of a species, but the 50/500 rule is the one generally adhered to by conservation biologists. 50 members of a species or population are needed for short term (100 years) survival and 500 needed for longer terms. As you can see, these numbers are quite small. Even a population in the low thousands would be large enough and genetically diverse enough to survive indefinitely so long as selection pressures remain stable.


The whole point of evolution theory is to prove how complexity occurred in life IMO.

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No, that is a common misconception. The point is to show how change occurs, increase in complexity is only one kind of observed change.

#50 de_skudd

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Posted 22 May 2009 - 01:01 PM

Absolutely! But beyond that, there's not a lot of agreement. Support some form of evolutionism, but which form? Acknowledge which gods, and which versions? Some simply worship themselves & assume their own assertions dictate reality; others pick and choose from the abundant cryptopantheon.

Ignorance plays a role also, as does the authority of the cryptopriesthood. How many even realize they need the Öort god?

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How about the Philosophical form of evolutheism? You know, there is no truth but my truth!! Crypto-philosopher!!! :)

#51 Bruce V.

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Posted 22 May 2009 - 02:30 PM

Do you disagree that this is what is observed in the fossil record? I could cut/paste articles and provide links if you want, but from the articles you've linked I imagine that you're pretty familiar with scientific literature.


This post by James is a great example of what I find compelling.

Hi Bruce,
    Welcome back! I have to say you are one of the most interesting creationists here. You have always seemed honestly interested in understanding the scientists or the opposing point of view, even when you disagree with it.

    As far as Tiktaalik, the most interesting part of the fossil is probably the neck region. It had the kinds of bones found in tetrapods (but not fish) that allowed the neck to move more like a tetrapod than a fish. It also had the kind of flat head, nostrils and eyes that are associated with an animal that could breath air to some degree and would put part of its head above water (like a crocodile).
Although Tiktaalik has many transitional features, no one can say for sure whether this animal evolved into tetrapods or whether this species is a branch off the main line. Often, when talking about these tetrapod-like fish, the diagram is something like this.

Posted Image

It shows each species as a branch off the main line. Until we get more fossil species filling out the branches, we can not say whether Tiktaalik was very close to the main 'fish to tretrapod line' or whether it is part of a longer branch off the 'fish to tetrapod' line.

Personally, I think one of the most important aspects of Tiktaalik was how it was found. Neil Shubin was specifically interested in finding the "fishapod" species between Eusthenopteron found in rock dated at 385 million years and Acanthostega and Ichthyostega dated closer to 365 million years.

To find such a species, Shubin knew he needed to look through exposed rock dated at 375 million years that came from a warm fresh water river environment. Geologists told him that such a place existed 700 miles north of the arctic circle on the south side of Ellsmere Island. Geologist say this area was also near the equator 375 million years ago.
Posted Image

    So Shubin wrote an NSF grant to fund a set of trips to Ellsmere Island to find this particular transitional species. After a long hunt Shubin and colleagues and his students found this fossil where they predicted it should be. And this 'fishapod' has many of the transitional features that they expected of such a species. This particular species has been found in no other locations so there is still lots to learn. They have found bones of other Tiktaalik, but no back legs yet. So I am sure they will go back.

    New transitional species are probably found almost every week. But the transitional species in the primate line and early tetrapod line get a lot more press. You won't get the same press if you find a trilobite that is transitional between a Silurian trilobite and a Devonian trilobite. Even a transitional between two early horse species or two diatoms just doesn't get people all that excited and it won't get the front page.

James

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The part that scientist went to Ellsmere Island to find a particular transitional species and found it is a very strong case. The science predicted where to look and why and they found it.

I posted a link where IRC stated that it would not qualify as a "missing link" which should be addressed.

In any case. If this is routine, where evolution points us in a direction and we find evidence that works out: I find that kind of evidence compelling. Are there more examples like that? I am asking you to bring out your best case and I will listen.

OTOH- We have been collecting and categorizing fossils for a very long time. We pretty much know what we will find in particular strata. Therefore, I would not find ad hoc examples compelling.

#52 jason777

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Posted 22 May 2009 - 03:21 PM

Absolutely. Observations of the fossil record indicate the following: That life changes over time, that these changes follow an observable trend, and that the trend is that life forms give rise to similar, but slightly modified forms.

This is something that many creationists will agree with, though they will insist that all variation occurs "within kind" and that the time-scale is different.


Have you ever looked at the fossil record?Go anywhere,and i mean anywhere,and you will not find anything of the sort.Piecing strata together by presupposition from different locations without evidence of erosion between layers is'nt evidence of anything.

Do you realy think that trilobites in the cambrian muav are anything like the orthocone nautiloids buried on top of them in the redwall limestone at the Grand Canyon?Thats not what i call an observable trend or slightly modified.

#53 jason777

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Posted 22 May 2009 - 03:24 PM

The part that scientist went to Ellsmere Island to find a particular transitional species and found it is a very strong case. The science predicted where to look and why and they found it.

I posted a link where IRC stated that it would not qualify as a "missing link" which should be addressed.

In any case. If this is routine, where evolution points us in a direction and we find evidence that works out: I find that kind of evidence compelling. Are there more examples like that?


Not much of a prediction,when you consider a Creationists would also predict to find an extinct fish in freshwater sediments.

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Posted 22 May 2009 - 05:46 PM

1.  Evolution:  Steven Gould professed punctuated equilibrium because the fossil record jumped from transition to transition abruptly leaving few transitional forms.  Why does fossil record go in Epochs.  Epochs and punctuated equilibrium go in the face of a gradual increasing complexity that Darwin predicted.

I think Gould (and Eldridge's) punctuated equilibrium is better described as the fossil record jumping from one discrete species to another similar species, but without evidence for the transitional individuals presumed to have existed. The key fact is that the 'sudden' change can easily be as long as a million years and thousands of generations. Quite enough for evolution to accomplish the change from species A to B. There is then good fossil evidence for the persistence of the before and after species without significant change over time.
In relation to major evolutionary change, such as from fish to land amphibians or reptiles, some of the long-lived species represent transitional forms, with some of the features of fish and some of the characteristics developed more fully in their descendants.

Some of the major geological eras are due to very substantial changes in the environment. The asteroid impact which seems largely responsible for killing off the dinosaurs is the best example. Cause of the extinction at the end of the Permian is less clear, but about 90% of species seem to have died relatively quickly.
After each of these catastrophes, life recovered relatively quickly (over 10s of millions of years) as surviving species diversified into empty niches. The 'Cambrian explosion' is just the first instance for such a divergence by species capable of leaving hard parts as fossils.

#55 Bruce V.

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Posted 23 May 2009 - 12:13 PM

I think Gould (and Eldridge's) punctuated equilibrium is better described as the fossil record jumping from one discrete species to another similar species, but without evidence for the transitional individuals presumed to have existed.  The key fact is that the 'sudden' change can easily be as long as a million years and thousands of generations.  Quite enough for evolution to accomplish the change from species A to B.  There is then good fossil evidence for the persistence of the before and after species without significant change over time.
In relation to major evolutionary change, such as from fish to land amphibians or reptiles, some of the long-lived species represent transitional forms, with some of the features of fish and some of the characteristics developed more fully in their descendants. 

Some of the major geological eras are due to very substantial changes in the environment.  The asteroid impact which seems largely responsible for killing off the dinosaurs is the best example.  Cause of the extinction at the end of the Permian is less clear, but about 90% of species seem to have died relatively quickly. 
After each of these catastrophes, life recovered relatively quickly (over 10s of millions of years) as surviving species diversified into empty niches.  The 'Cambrian explosion' is just the first instance for such a divergence by species capable of leaving hard parts as fossils.

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Hi Kieth,

The question I have is why are there gaps in the fossil record? What is your favorite theory?



(the following information is from the book: Design of Life Pages 71-72. Expect typing mistakes :huh: .


These are 4 theories why evolution of why there are gaps in the fossil record.

1. Imperfect record:  Only a small fraction of the organisms that lived in the past have been preserved as fossils.  It is unlikely that future research will fill the gaps.  Support for evolution must look beyond the fossil record.

2.  Insufficient Search:  The gaps result from a failure to examine the fossil bearing strata thoroughly enough.  The gaps will close as a more complete sampling is taken.

3. Punctuated Equilibrium:  Evolution is a jerky process.  Evolution happens in small, isolated populations, punctuating an otherwise stagnant equilibrium.  Although transitional forms must have existed, few if any get preserved.

4.  Abrupt Emergence: The gaps are real and reflect fundamental discontinuities in nature. Basic groups of organisms emerged suddenly.  Transitional forums connecting their basic groups never existed.

We could spend time on each if you want but I will discuss item 2 in this post.

2.  Insufficient search: ... Exhaustive searches confined to individual locales have been conducted in sediments where such transitional forms were thought to be most likely . Yet, even in the most favorable circumstances, paleontologist have consistently failed to discover the missing links that would connect organisms from higher levels  of classification.  IT is fair to say that paleontologists have engaged in heroic efforts to find missing links, searching though thousands of feet of sediment and sorting through tons of hard rock (not just sandstone or shale but quartzite needing to split into slabs.)
...
This is e quote from Micheal Denton:
...
The fundamental problem in explaining the gaps in terms of an insufficient search or in terms of the imperfection of the record is their systematic character- the fact that there are fewer transitional species between major divisions than between the minor.... And this rule apples universally throughout the living kingdom to all types of organisms, both those that are poor candidates for fossilization such as insects and those which are ideal, like mollusks.  But this is the exact reverse of what is required by Darwinian evolution.  Discontinuities we might be able to explain away in terms of some sort of sampling errors, but their systematic character defies all explanation.

The section ends with this

... for every link connecting minor divisions there should be hundreds connecting major divisions.


Maybe tiktaalik is an exception and is a missing link that was found where evolutionist told us to look - maybe not. Are there other examples that could exceptions: missing links found where evolutionist told us to look?

Bruce

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Posted 24 May 2009 - 06:05 PM

The question I have is why are there gaps in the fossil record?  What is your favorite theory?

Maybe tiktaalik is an exception and is a missing link that was found where evolutionist told us to look - maybe not. Are there other examples that could exceptions: missing links found where evolutionist told us to look?

I think all those different explanations are partially correct.
What I think is most important for the public perception is that the bigger and better-known fossil species are relatively long-lived animals. Also the larger predators like T Rex must have been far less numerous than the dinosaurs they consumed.

Somewhere on another thread in this forum I posted info on T Rex fossils. That species existed for about 3 million years and we have found about 30 specimens. That is one from about every 100,000 years. This is for very large bones which are easy to spot as fossils and found in arid western ESA where exposure by erosion is relatively rapid.
I do not know what species is believed to be the immediate ancestor of T Rex, or whether there are known fossils which are somewhat intermediate between this ancestor and T Rex, but suppose that transition required 200,000 years, but the population of these intermediates averaged about half as many as the eventual T Rex population. This would suggest 1 transitional fossil.
Would we be able to identify this as transitional or just classify it as T Rex with some archaic features.

The real date on fossil transitions between species comes from species like foraminifera, where large numbers of individuals have been recovered as fossils from cores from undisturbed ocean sediments. Much less spectacular than dinosaurs.

As to other predictions of fossil finds, Darwin suggested Africa for human origin. I also believe that the recent whale transitional species were found by looking in sediments of the right age and environment.
Marsupials are another example. Earliest marsupial fossils are from North America, around 80 million years ago. They spread through South America and now are found mainly in Australia. Continental drift data shows that marsupial ancestors could have migrated via Antarctica before Gondwanaland broke up completely. Sure enough, they were there.
http://www.nytimes.c...mal-fossil.html

#57 Bruce V.

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Posted 26 May 2009 - 12:52 PM

Marsupials are another example.  Earliest marsupial fossils are from North America, around 80 million years ago.  They spread through South America and now are found mainly in Australia.  Continental drift data shows that marsupial ancestors could have migrated via Antarctica before Gondwanaland broke up completely.  Sure enough, they were there.
http://www.nytimes.c...mal-fossil.html

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Hi Keith,

I looked into marsupial evolution as best I could. I am trying to figure out fossils with little luck.

1. The article you provided does not discuss the marsupial fossil found in Antarctica as being a transitional fossil. Rather it explains a South America and Australian connection for marsupials. This article goes into more information. It shows the Jaw bone found. ( I can't link the image :lol: ) The jaw bone isn't much to go on IMO.

2. Evolutionist find marsupial and placental mammals conflicting and puzzling. link Link 2

Switcheroo:  Fossil marsupials are predominately found in North America, but living ones are primarily found in Australia and South America.  “This geographical switch remains unexplained.  The timing of the split between eutherians [placental mammals] and metatherians [marsupials] is also controversial.”

Known Bones:  “To date, the geological record has yielded few fossils that bear directly on the origin of marsupials.”

Good News, Bad News:  This new, exciting, earliest fossil marsupial was found in China, but “The balance of paleontological and morphological data suggests that the last common ancestor of metatherians and eutherians was Laurasian” (i.e., European-North American].

Divergence and Convergence:  “Clearly, the relative successes of the two groups differed widely on the two continents.  Yet, the early representatives of both groups seem to have been highly similar ecologically--most were small, insectivorous, and probably nocturnal.  This puzzle remains to be resolved.”  It is also commonly known that many marsupials, such as the marsupial wolf, have placental look-alikes, yet very different reproductive systems.

DNA Doubts:  “Molecular data have yielded conflicting results for the timing of the metatherian-eutherian split.”  Molecular estimates are usually much older than fossil estimates.

The Gap Theory:  “These divergence estimates have implications for the relative timing of most other divergences on the mammalian family tree.  However, they are difficult to reconcile with the (admittedly imperfect) mammalian fossil record.  When the entire tree is considered (top panel), it becomes clear that large gaps in the fossil record (most with durations of more than 30 million years) must be inferred to explain the distribution of each group represented.”

Tooth Truth:  Paleontologists attempt to classify the groups based on teeth, but its a difficult job: “But such criteria are not applicable to dentally more primitive fossils.  Furthermore, they are of limited utility when it comes to assessing which biological niches they might have occupied, beyond the suggestion that most early metatherians fed on animal tissues ranging from insects to meat, depending on body size.”

Why We Gotta Figure This Out: “The paleontological evidence is important because it provides an independent test for dates based on molecular data.  It also provides some basis for calculating the rates of change of skeletal (and dental) morphology and molecular structure.  Given the far-reaching implications for evolutionary studies, it is crucial that the widely differing estimates of divergence time are reconciled and that the place of origin of both metatherians and eutherians is further elucidated with fossil discoveries.  The many open questions provide fertile ground for future and paleontological studies.”


3. Kiwi ghost New Zealand wasn’t supposed to have any native mammals, but bones of a small rodent near Otago on the South Island were reported in PNAS. The discoverers said this points to a “ghost lineage” of one or more mammals that must have inhabited the isolated archipelago. Since they dated the mammal in the Miocene (19-16 million years ago), they are puzzled that it seems to represent an early rodent that pre-dates the split of marsupials and placentals assumed to have occurred in the early Cretaceous 125 million years ago. That means that mammals must have existed in New Zealand for over 100 million years, but as yet, no other traces of them have been found.

Marsupials fossils does not look like solid proof for evolution IMO.

#58 jason777

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Posted 26 May 2009 - 03:23 PM

Hi Bruce,

DNA Doubts:  “Molecular data have yielded conflicting results for the timing of the metatherian-eutherian split.”  Molecular estimates are usually much older than fossil estimates.


Paleoentologists and geneticists data conflict a majority of the time,but they try to give the illusion that they agree.

Geneticists calculated the divergence of monotremes at ~20-30 million years ago,but the fossils say 120 million.

There is not much of a fossil record of monotremes, so it has never been clear when the platypus and the echidnas (also known as spiny anteaters) diverged. Most estimates using genetic analysis — looking at the rate of mutations — suggest that they split perhaps 20 million to 30 million years ago, although a few stretch that from 80 million years.

Now Timothy Rowe of the University of Texas and colleagues report in The Proceedings of the National Academy of Sciences that the divergence may have occurred long before that. They used X-ray computer tomography to examine a 120-million-year-old fossil, Teinolophus trusleri. It is an ancestral platypus, they say, with some similar morphological features, in particular a canal in the jaw that the researchers say is evidence that Teinolophus had a duckbill.

The researchers conclude that the platypus and echidna branches of monotremes were already distinct at that early date. The findings also suggest that monotremes diversified at a slower rate than the other mammals.


http://www.nytimes.c...e/29obplat.html



Then there is the problem of trying to figure out how the platypus had such a wide distribution (from Australia to Argentina) without showing a much wider phenotype variation.

The Platypus (Ornithorhynchus anatinus) is a unique Australian species. Along with echidnas, Platypus are grouped in a separate order of mammals known as monotremes, which are distinguished from all other mammals because they lay eggs.

The fossil record for monotremes is poor in comparison to that of other groups of mammals, and until recently little was known about their evolutionary history. Several fossil discoveries since the early 1970s have shed some light on the origins of monotremes. We now know that monotremes were present in Australia during the Mesozoic Era, when Australia was still part of the supercontinent, Gondwana. The fossil evidence suggests that monotremes originated and diversified in the Australian/Antarctic section of Gondwana, and that there was only a single dispersal to South America before the break up of Gondwana.

Four species related to Platypus have been found in fossil deposits from Australia, including a complete skull of Obdurodon dicksoni and an opalised jaw fragment of Steropodon galmani. The latter is 110 million years old and represents one of Australia's oldest mammals. The only evidence that Platypus ancestors were once present outside Australia came in 1991, when a 61 - 63 million year old fossil tooth was found in Patagonia, in southern Argentina.

Studies of these fossils indicate that the one remaining living species of Platypus is more specialised than its predecessors. It is smaller, its functional teeth have been replaced by horny pads and other aspects of its anatomy appear simpler. It also appears to have a more restricted distribution, being confined to the river systems of eastern Australia. Although Platypus remains widespread and reasonably common, this trend towards increasing specialisation suggests that it may be moving out onto an evolutionary 'limb' and that its current status should not be taken for granted.



#59 Guest_Keith C_*

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Posted 26 May 2009 - 05:56 PM

I looked into marsupial evolution as best I could.  I am trying to figure out fossils with little luck.

1.  The article you provided does not discuss the marsupial fossil found in Antarctica as being a transitional fossil. Rather it explains a South America and Australian connection for marsupials. This article goes into more information. It shows the Jaw bone found.  ( I can't link the image  :angry: ) The jaw bone isn't much to go on IMO.

Marsupials fossils does not look like solid proof for evolution IMO.

The question I was asked was whether there were examples, other than Tiktaalic, of fossils found where they had been predicted.
Marsupials on Seymour island is a good example.
I agree that the jawbone is not impressive, but is that significant?
Do you think it was mis-identified?

I fail to see the relevance of uncertainties about the branching between marsupial and mammal ancestors around 150 million years ago to evidence of land migration from South America to Australia via Antarctica around 40 million years ago.
Evidence always becomes scarcer with the passage of time. It is particularly difficult for mammals and marsupial before 65 million years ago because dinosaurs were dominant and these other species were small and leave very fragmented fossils.

Their greatest contribution to evolution is proof that creatures with some mammalian characteristics (warm blooded, fur-covered etc) existed. Marsupial and monotreme ancestors fill some of the gap between reptiles and mammals.
I think a good practical rule is to look for evidence where it can be found in more recent fossils which are larger and better preserved, rather than complain about what is missing.

Your post included a long paste from a creation website, but without providing a link.
I do not know whether you have read any of the scientific evidence carefully and considered which of the pasted point are really relevant.

#60 jason777

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Posted 26 May 2009 - 06:58 PM

There is evidence of mammals having modern features from their very appearance in the fossil record.In fact,we know that gliding mammals were already taking to the air millions of years before dinosaurs were.Why did'nt mammals evolve feathers and a more advanced form of flight ? Bats are a completely different family and their is no evidence connecting the two.They both appear fully formed with no transitionals.

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Thanks.




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