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Author Topic:   Living fossils expose evolution
Lithodid-Man
Member (Idle past 2198 days)
Posts: 504
From: Juneau, Alaska, USA
Joined: 03-22-2004


(3)
Message 25 of 416 (527000)
09-30-2009 12:26 AM
Reply to: Message 5 by Calypsis4
09-29-2009 8:40 PM


Magnolias, Bat, Crayfish, and Opposum
First on Magnolias. I am not a botanist, so will just make a brief commentary here. Magnolia trees have a relatively conserved form, yet are taxonomically highly diverse. The original genus Magnolia is probably going to be divided (if not already) into several genera and probably several families even though the gross leaf morphologies are identical to the untrained eye. I will send an email request to a Magnoliacea taxonomist I know and see what the current status is. A google search suggests that M. magnifolia is a living species found in Columbia.

Now the bat. The picture you showed is Onychonycteris. This differs from all living bats in many fundamental ways and is, in fact, a long awaited transitional. While capable of true flight, it was what is called a 'flutter glider' which is exactly what we would expect if, as proposed, bats evolved from a gliding ancestor similar in form (but not related to) flying squirrels. The diagram you show in another post of proposed bat evolution is a terrible strawman, btw. and not supported by anyone I am aware of. The arm to leg ratio of Onychonycteris is exactly in between (but not clustered with!) volant and non volant mammals. It also could not echolocate and had well-developed claws on all 5 digits, which modern bats do not have. Very poor example of a 'living fossil'!

The crayfish is probably the most interesting to me. While it does look somewhat like a crayfish, the fossil you show is Eryma. There are no members of this genus alive today, actually no members of its family or superfamily! It is as closely related to modern crayfish as are Maine lobsters (which is not close at all). Another very poor example of a 'living fossil'.

Now onto the so-called opossum.The term "similar to an opossum" must have been a reference to rough size and shape (and little else!). The fossil is Gobiconodon, which is a Triconodonta. In case you do not know, modern mammals are divided into three large clades, the monotremes, the marsupials, and the eutherian (placentals), with the latter two having diverged later. Well Triconodonta are a completely other clade of mammals that stands apart from both marsupials and eutherians. Triconodonts went extinct during the Mesozoic and left no descendants. Their tooth morphology is unique to that group and very distinctive. Phylogenetically you would have been better off showing a fossil giant wombat (rhino sized) next to an American opossum skeleton as they are far more similar than Gobiconodon is to any marsupial! Again, a very poor example of a 'living fossil'!


Doctor Bashir: "Of all the stories you told me, which were true and which weren't?"
Elim Garak: "My dear Doctor, they're all true"
Doctor Bashir: "Even the lies?"
Elim Garak: "Especially the lies"

This message is a reply to:
 Message 5 by Calypsis4, posted 09-29-2009 8:40 PM Calypsis4 has taken no action

Replies to this message:
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Lithodid-Man
Member (Idle past 2198 days)
Posts: 504
From: Juneau, Alaska, USA
Joined: 03-22-2004


(2)
Message 67 of 416 (527128)
09-30-2009 10:51 AM
Reply to: Message 42 by Calypsis4
09-30-2009 9:49 AM


Microbiology
If you have ever worked with bacteria, protists, and the like you will know that external appearance is probably the worst possible way to distinguish genera, families, sometimes even phyla. For example, the Ciliophora (protozoans like the famous paramecium)contain members that cannot be reliably identified to subclass without tedious and careful fixation to illuminate the number and structure of feeding grooves. These structures are unlikely to ever fossilize. Your author could have easily shown a fossil ciliate and a living one and claimed no change but we would no way of telling if the fossil were even distantly related to the living specimen despite 'identical' appearance.

Bacteria are even worse. Fossil bacteria, despite amazing preservation, still allow us to only see the gross external morphology. Microbiologists use a number of chemical assays to determine even higher level identification of bacteria. Genetic studies have furthered our understanding of just how diverse 'bacteria' really are, splitting them into two kingdoms. I would challenge you that if I showed you two ESM photos of bacteria from two different kingdoms you could not tell me which was which.

Your fossil blue-green is Palaeolyngbya. Just fyi, this genus is linked to the Oscillatoriaceae only because some fossils show what is interpreted as the 'sheath' characteristic of this family. Even if they do belong to this family it does not 'expose evolution' as Mark24 said here, evolution does not expect everything to be changing gross external morphology.

You really may want to start critically examining your source. Despite your denial it has been wrong on all examples you gave and fraudulent about Gobicodon. I do not have this book (although I will get it) but so far it seems to be the same material presented at the Harun Yahya pages and fails by the same standards. I do look forward to your addressing my points in Message 25, especially about Gobicodon and the Eryma crayfish.


Doctor Bashir: "Of all the stories you told me, which were true and which weren't?"
Elim Garak: "My dear Doctor, they're all true"
Doctor Bashir: "Even the lies?"
Elim Garak: "Especially the lies"

This message is a reply to:
 Message 42 by Calypsis4, posted 09-30-2009 9:49 AM Calypsis4 has replied

Replies to this message:
 Message 85 by Calypsis4, posted 09-30-2009 11:23 AM Lithodid-Man has replied

Lithodid-Man
Member (Idle past 2198 days)
Posts: 504
From: Juneau, Alaska, USA
Joined: 03-22-2004


(2)
Message 81 of 416 (527145)
09-30-2009 11:13 AM
Reply to: Message 70 by Calypsis4
09-30-2009 10:58 AM


Re: Living fossils expose evolution??
This is too funny! Your fossil "tiger" is a hyena. I cannot find the ref, but is one of those Miocene (iirc) mammal fossils that are so beautifully preserved. Look at the molars and the skull vault. Harun Yayha is a really bad source of info. You do know that hyena's and tiger's are different families, right?


Doctor Bashir: "Of all the stories you told me, which were true and which weren't?"
Elim Garak: "My dear Doctor, they're all true"
Doctor Bashir: "Even the lies?"
Elim Garak: "Especially the lies"

This message is a reply to:
 Message 70 by Calypsis4, posted 09-30-2009 10:58 AM Calypsis4 has replied

Replies to this message:
 Message 87 by Calypsis4, posted 09-30-2009 11:39 AM Lithodid-Man has taken no action

Lithodid-Man
Member (Idle past 2198 days)
Posts: 504
From: Juneau, Alaska, USA
Joined: 03-22-2004


(2)
Message 84 of 416 (527150)
09-30-2009 11:20 AM
Reply to: Message 77 by Calypsis4
09-30-2009 11:07 AM


Re: Living fossils expose evolution??
I wish I didn't have to go to work, I could do this all day!

Icarosaurus is a diapsid in the extinct order Eolacertilia. The modern flying lizard, Draco, is in the order Squamata which includes true lizards, worm lizards, and snakes. So while a similar gliding mechanism is used, these are very different 'kinds' of animals.


Doctor Bashir: "Of all the stories you told me, which were true and which weren't?"
Elim Garak: "My dear Doctor, they're all true"
Doctor Bashir: "Even the lies?"
Elim Garak: "Especially the lies"

This message is a reply to:
 Message 77 by Calypsis4, posted 09-30-2009 11:07 AM Calypsis4 has replied

Replies to this message:
 Message 98 by Calypsis4, posted 09-30-2009 12:38 PM Lithodid-Man has replied

Lithodid-Man
Member (Idle past 2198 days)
Posts: 504
From: Juneau, Alaska, USA
Joined: 03-22-2004


(2)
Message 111 of 416 (527187)
09-30-2009 1:28 PM
Reply to: Message 91 by Calypsis4
09-30-2009 12:02 PM


Another poor example!
Your fossil ophiuroid is Ophiopetra, probably O. lithographica if the locality is accurate. Ophiopetra is an extinct genus in an extinct family (Aplocomidae). It does belong to the extant suborder Chilophiurina.

Ophiopholis, an the other hand (btw, the photo is of Ophiopholis japonica, I have seen thousands of these on deep sea corals) is an ophiuroid but a completely different suborder, Gnathophiurina.

Unlike bacteria, the carbonate skeletons of echinoderms fossilize very well and we can resolve their taxonomy with fair accuracy. Your brittle stars are different suborders with dramatically different features.


Doctor Bashir: "Of all the stories you told me, which were true and which weren't?"
Elim Garak: "My dear Doctor, they're all true"
Doctor Bashir: "Even the lies?"
Elim Garak: "Especially the lies"

This message is a reply to:
 Message 91 by Calypsis4, posted 09-30-2009 12:02 PM Calypsis4 has taken no action

Lithodid-Man
Member (Idle past 2198 days)
Posts: 504
From: Juneau, Alaska, USA
Joined: 03-22-2004


(2)
Message 114 of 416 (527191)
09-30-2009 1:50 PM
Reply to: Message 112 by Calypsis4
09-30-2009 1:34 PM


Re: Magnolias, Bat, Crayfish, and Opposum
Calypsis writes:

So what did this species of ants evolve from?

Probably something like Sphecomyrma, an 80 myo ant that combines features of modern ants and vespoid wasps. Another beautiful transition between forms! You can read the full text of the species description here

Now please explain the Gobicodon and crayfish examples, and discuss the other examples you have given before posting more. I will say again, not one is really even a 'true' living fossil as you are imagining and none damage evolution in any way.


Doctor Bashir: "Of all the stories you told me, which were true and which weren't?"
Elim Garak: "My dear Doctor, they're all true"
Doctor Bashir: "Even the lies?"
Elim Garak: "Especially the lies"

This message is a reply to:
 Message 112 by Calypsis4, posted 09-30-2009 1:34 PM Calypsis4 has taken no action

Lithodid-Man
Member (Idle past 2198 days)
Posts: 504
From: Juneau, Alaska, USA
Joined: 03-22-2004


(2)
Message 174 of 416 (527268)
09-30-2009 4:50 PM
Reply to: Message 98 by Calypsis4
09-30-2009 12:38 PM


Re: Living fossils expose evolution??
Calypsis writes:

Really? So why do Russian scientists place them in the same category as 'gliding lizards'?

So if I list a weasel, a lion, a killer whale, and a little brown bat and call them "predatory mammals" am I saying that they are then all the same kind or closely related?

And who determines what is a 'true lizard'? The point is that they are both lizards.

Herpetologists who study lizards and know the precise morphological characters that define squamatids from other lepidosaurans. By your same definition then pterosaurs and plesiosaurs are also lizards.

Didn't you notice that Dr. Werner pointed out that they were different species of lizard ("Now compare the different genus names in blue". Why did you overlook that? Well, you are missing the point of the whole thread to begin with so why should we be surprised?

Hey now! I did not overlook that. However, a different genus is not the same as different orders. If I had to guess why he pointed out the genus names was to imply that we are somehow trying to call these things something different when anyone can see they are the same. But without the ref I cannot tell what he was getting at. And by the way, I get the point of your thread. It is not that complex. I question whether you get the point of this thread.

But you are free to post pictures of the step by step changes from gliding lizards (be they Icarosaurus or draco, take your pick) to another kind of organism.

Because that would be off topic and NOT the point of this thread.


Doctor Bashir: "Of all the stories you told me, which were true and which weren't?"
Elim Garak: "My dear Doctor, they're all true"
Doctor Bashir: "Even the lies?"
Elim Garak: "Especially the lies"

This message is a reply to:
 Message 98 by Calypsis4, posted 09-30-2009 12:38 PM Calypsis4 has taken no action

Lithodid-Man
Member (Idle past 2198 days)
Posts: 504
From: Juneau, Alaska, USA
Joined: 03-22-2004


(1)
Message 181 of 416 (527279)
09-30-2009 5:05 PM
Reply to: Message 85 by Calypsis4
09-30-2009 11:23 AM


Re: Microbiology
Calypsis writes:

Appearance, function, homology, etc. are all factors. But the homology of organisms that have been dead for eons of time is very difficult unless we happen to come across a T-Rex with soft tissue and viable blood cells.

Please explain "homology of organisms" as I do not think you are using the term to mean the same thing it means when I use it. Especially with the next sentence. Do you mean homologous proteins or genes? We do not need long-dead species to find those, in fact living representatives are much better. T-Rex with viable blood cells? Man, wouldn't that be amazing if it ever happened? Too bad it is impossible!


Doctor Bashir: "Of all the stories you told me, which were true and which weren't?"
Elim Garak: "My dear Doctor, they're all true"
Doctor Bashir: "Even the lies?"
Elim Garak: "Especially the lies"

This message is a reply to:
 Message 85 by Calypsis4, posted 09-30-2009 11:23 AM Calypsis4 has replied

Replies to this message:
 Message 184 by Calypsis4, posted 09-30-2009 5:19 PM Lithodid-Man has taken no action

Lithodid-Man
Member (Idle past 2198 days)
Posts: 504
From: Juneau, Alaska, USA
Joined: 03-22-2004


(5)
Message 255 of 416 (527437)
10-01-2009 10:47 AM
Reply to: Message 247 by Calypsis4
10-01-2009 9:23 AM


Fun with Decapod Taxonomy
On crayfish...
Calypsis writes:

Why? I think my point was succinct. No further discussion on that is needed.

Please forgive the detailed explanation here, but I think it is important. Unfortunately for the layman, there are no good explanations of crustacean (or most inverts, really) higher level taxonomy. This group lends itself to the kind of 'common term' lumping despite the enormous and profound variation present. In my opinion this is an argument why the higher-level Linnaean system is inadequate as I would argue the differences between orders of crusties and orders of say mammals are incomparable. This is probably due to species bias (we recognize differences more in things that look like us). Anyway, that is another topic...

Decapod crustaceans (those with 5 pairs of walking legs and three pairs of legs forming mouthparts) are divided into several Infraorders. The infraorder Brachyura, for example, are the 'true crabs' and include forms like the blue crab, the Dungenness crab, and the snow crab (but not the king crabs). Infraorder Palinura contains the spiny lobsters, slipper lobsters etc. and the infraorder Caridea contains the true shrimp (but not the Gulf and tiger prawns).

The infraorder in question here, the Astacidea, contains the freshwater crayfishes and the clawed lobsters. The overall body shape in this group is fairly conserved, with most having an elongate body, well-developed tail, and claws on the first three walking legs (this is important!).

This group is further subdivided into superfamilies.
-Superfamily Astacoidea which includes the living
Laurasian freshwater crayfish and some extinct marine
forms.

-Superfamily Parastacoidea are the Gondwana freshwater
crayfish (similarities to northern crayfish convergence
rather than phylogenetic).

-Superfamily Nephropoidea are the clawed lobsters
(including the American lobster).

-Superfamily Glypheoidea are a bizarre group known mainly
from fossils and a single living species.

-Superfamily Enoplometopoidea includes the reef lobsters
and many extinct forms.

-Superfamily Erymoidea which is an extinct group
containing several families.

The last two superfamilies are the ones of interest here. Your fossil, Eryma, is a very widespread and well known group of species. They have some features in common with the Enoplometopoidea but none of the other supefamilies. The most important one is the presence of a unique structure on the pleopod (swimmerette) called an appendix masculina. Both Erymoids and Enoplometopoids have this which strongly suggests a relationship. The reef lobsters posses claws only on the first pair of walking legs and subchelae on the next two. The position and presence of chelae is taxonomically important in the decapods. Erymoids differ by having chelae on the first three walking legs.

The purpose of this was to demonstrate that despite superficial appearance, Procambarus is not closely related to your fossil Erymid. Not the same family, not even superfamily. It is not some arbitrary classification ("it is old so it must be a different name"), it is based on cladistic analysis that while not perfect, have proven to be exceptionally accurate when dealing with decapoda (i.e. the method meshes beautifully with genetic analysis).

Current classification scheme based on:

Amati L, Feldmann RM and Zonneveld J (2004) A new family of Triassic lobsters (Decapoda: Astacidea) from British Columbia and its phylogenetic context. Journal of Paleontology 78(1): 150-168.


Doctor Bashir: "Of all the stories you told me, which were true and which weren't?"
Elim Garak: "My dear Doctor, they're all true"
Doctor Bashir: "Even the lies?"
Elim Garak: "Especially the lies"

This message is a reply to:
 Message 247 by Calypsis4, posted 10-01-2009 9:23 AM Calypsis4 has taken no action

Lithodid-Man
Member (Idle past 2198 days)
Posts: 504
From: Juneau, Alaska, USA
Joined: 03-22-2004


(2)
Message 278 of 416 (527498)
10-01-2009 3:08 PM


Frustration?
Calypsis -

I am surprised that you seem to want to duck out of here. I have to say I am somewhat disappointed that you ignored the majority of my posts here, and those you did respond to were to the more unimportant points. In fact, your most substantive reply to me was the one where you implied that my missing a detail (which I did not) was indicative of a larger cognitive problem I must have. Personally I took offense, but let it go in the hope that you eventually actually address my points.

The only real mention of my points has been when you answer someone else's post who refer to mine. And that is to dismiss them without cause. For the most part you have just ignored me and gone on claiming your original point is true. And I would argue not in the most honest fashion.

For example on your original post about your crayfish you said "The living crayfish appears that it could be used to make the very impress of the fossil crayfish" Yet when reminded it is a different family (actually superfamily) you said "You didn't tell the truth. You cannot determine that the fossil crayfish is a different kind than what was posted in the picture because it is too obscure to determine the details" So is it so clear it could be an imprint or so obscure it could be anything?

I really want you to address why your author pictured the reconstructed skeleton of a triconodont mammal next to a marsupial and claimed they were the same 'kind'. Triconodonts are a very unique, very distinct subclass of Mesozoic mammals that have been known for 150 years. No mammal before or since has their three-coned tooth pattern. You said the postcranial skeleton looks the same to you. I am going to argue you would say the same if it were a muskrat, a hyrax, or a meercat skeleton next to Gobicodon. Most mammal skeletons have the same basic shape. You are not a vertebrate taxonomist. Here I believe your Carl Werner is either pitifully ignorant or (more likely) deliberately fraudulent.

So I ask you - please specifically address the points I have made. preferably without insult as I have not in any way been disrespectful to you.


Doctor Bashir: "Of all the stories you told me, which were true and which weren't?"
Elim Garak: "My dear Doctor, they're all true"
Doctor Bashir: "Even the lies?"
Elim Garak: "Especially the lies"

Lithodid-Man
Member (Idle past 2198 days)
Posts: 504
From: Juneau, Alaska, USA
Joined: 03-22-2004


(2)
Message 350 of 416 (527826)
10-02-2009 6:43 PM
Reply to: Message 303 by Calypsis4
10-02-2009 12:14 PM


Re: Classifications
Calypsis -
Calypsis writes:

One of the problems in classifying fossils (including living fossils) is the obscurity of some samples; i.e. the crayfish example.


and
Calypsis writes:

But what is true about this is not true about the crayfish and other examples posted on this thread. It was immediately identified as a 'crayfish' by all who observed it. We can bicker and dicker about classification but if observation of the evidence is of any true value then there has been no evolutionary change in the organisms so depicted.

Are my posts getting filtered out somehow before they get to you? I addressed your 'crayfish' in several posts now, and apparently was a waste of my time as you are going on as if your pictures settled this issue way back at the beginning of this thread.

Eryma is NOT a crayfish, it is distantly related to crayfish. The example you posted is not the only one, we have hundreds of Erymids in several families with several genera and dozens of species. We have fossils of their copulatory structures that show beyond any doubt that they are not closely related to crayfish but may be related to living reef lobsters. No amount of 'it looks like one to me' and flat out ignoring me is going to make Eryma a crayfish. This is an aside to the issue of why living fossils are not devastating to evolution, this one (and pretty much the majority you posted) simply are not living fossils anyhow.

Now back to Onychonycteris. I want to provide two scenarios which I hope you can picture that might help you see the issue we keep presenting.

The claim "it is still just a bat" is a time tested and tru creationist tactic. Yes it is a bat, and all living bats are bats as well. If a million years from now some island species of bat is a flightless ground predator (as featured in Primeval) creationists of that day will still say "it's just a bat"


Click to enlarge
And they would, in some way be correct. If ten million years later some descendant looked pretty much like a furry bunny, it would still be "just a bat" even though it may be called something else.

Likewise, if using our time machine we were presented with the fauna of 55-50 mya, we might see something we would call the 'gliding shrew'. One when scientists discovered a species that fluttered and glided, with true powered flight, those imaginary creationists would say "so, it flies. It is still gliding shrew kind"

As for the ancestors of Onychonycteris, I have high hopes they will be found. Do I believe their discovery will change your mind? Not at all. No more than the discovery in the last several decades of a nearly perfect chain of transitions between terrestrial artiodactyls and modern whales changed anything in creationist literature.

My guess is that when we find fossils of the 'gliding shrew' we will discover we have known about it (or the group it belongs to) for some time just didn't realize what it was. I am going to end this with two pictures, one of a squirrel and the other a flying squirrel to show that one needs very specific skeletal elements to identify a glider from a non-glider.


Click to enlarge

Click to enlarge


Doctor Bashir: "Of all the stories you told me, which were true and which weren't?"
Elim Garak: "My dear Doctor, they're all true"
Doctor Bashir: "Even the lies?"
Elim Garak: "Especially the lies"

This message is a reply to:
 Message 303 by Calypsis4, posted 10-02-2009 12:14 PM Calypsis4 has taken no action

Lithodid-Man
Member (Idle past 2198 days)
Posts: 504
From: Juneau, Alaska, USA
Joined: 03-22-2004


(1)
Message 359 of 416 (527846)
10-02-2009 8:24 PM
Reply to: Message 356 by Calypsis4
10-02-2009 7:42 PM


Ginkgos??!!!
Ginkgos? Really Calypsis? That is your answer to the single question you have been asked dozens of times by multiple poster?

What makes you think your statement "Now let me point out that scientists can find NO transitional forms either before or after this fossil" is true? You sincere desire that it be so? Because the evolution of the DIVISION Gingophyta (fyi, Division is what botanists call phyla) is quite well understood. You see, several known members of the division Pteridospermatophyta, order Peltaspermales closely resemble Gingkophytes and in fact with some of these and early Gingkophytes there is some question as to which group they should be grouped with (Meyer, 1987). You see, you can not get a better example of a transitional when the actual experts who study the taxon cannot decide which side of the 'fence' it should fall. I am looking at two references now, both of which seem to believe that the ancestors of your Gingko are very well known and rather firmly established (Royer et al., 1987; Meyer, 1987) But hey - what do those guys know? They are only paleobotanists.

Meyer (1987) Basic features of gymnosperm systematics and phylogeny as evidenced by the fossil record. Botanical Review 50(1): 1-111.

Royer DL, Hickey LJ, and Wing SL (1987) Ecologic conservatism in the "living fossil" Gingko. Paleobiology 29(1): 84-104.


Doctor Bashir: "Of all the stories you told me, which were true and which weren't?"
Elim Garak: "My dear Doctor, they're all true"
Doctor Bashir: "Even the lies?"
Elim Garak: "Especially the lies"

This message is a reply to:
 Message 356 by Calypsis4, posted 10-02-2009 7:42 PM Calypsis4 has taken no action

Lithodid-Man
Member (Idle past 2198 days)
Posts: 504
From: Juneau, Alaska, USA
Joined: 03-22-2004


(4)
Message 367 of 416 (527878)
10-03-2009 2:17 AM
Reply to: Message 363 by Arphy
10-02-2009 10:21 PM


Stasis, PE, and Gould
Hi Arphy,

I wanted to address a few points in your posts. From reading a few of your other posts in the past you seem like a very reasonable person.

First - be very suspicious of creationist sources that cite Gould. I will be the first to admit that Gould has said some very odd things. But more often than not (and by that I mean always) creationist sources love to misinterpret Gould. Again, I am afraid he often set up the situation which allows that to be possible (he tended to speak and write in grandiose terms).

In the work your source cites they are in fact citing Gould correctly but are using the quotes to support a different concept. Notice the repeated use of the word 'species' throughout. He is using the term as biologists (and most everyone) use the term. He is NOT talking about larger taxonomic categories, what creationists would call 'kinds'.

What Darwin expected, and he was incorrect in many (but not all cases) was that we would see a smooth transition from one species to another in the geologic record. What has been found is that we find individual species remain static, then seem to abruptly change to another species that remains static and so on. Eldredge and Gould argued that this was not an artifact of an incomplete fossilization record but the nature of speciation. Again note this is species and speciation, change that pretty much all creationists are comfortable with as it is 'microevolution'.

This does not in any way replace gradual change, Gould acknowledges that gradual change is the rule, but that apparent change in the fossil record is quick.

Picture a large population of snails with smooth shells that occupy a valley. The majority of that population have smooth shells so as they die they record layer after layer of that species with smooth shells. Meanwhile, on the fringe of that population a group that is heavily preyed upon are gradually developing thicker shells with spines. After a few thousand years the environment changes and suddenly the predator can exploit the whole population. In a few generations the thick-shelled spiny genes swamp the whole population.

What would that look like to a paleontologist studying the fossils of this snail? Would you expect to see smooth snails gradually changing to spiny ones or would it seem like they abruptly morphed into another species? Darwin predicted the former, facts revealed the latter. Darwin wasn't altogether wrong, change does go by increments, but apparent change in the fossil record appears saltational because the main body of a population remains stable while change occurs in fringe or isolated populations. That is punctuated equilibrium.

Note - we also have found examples of species that do change gradually over time as well, PE does not describe all cases of speciation.

Your source is trying to make you think that Gould doubted that 'kinds' have intermediates that are are seen to gradually appear in the fossil record. This is blatantly false. Transitions between what creationists call kinds, whether it be defined as genus, family, phyla, etc. are well know for a huge number of groups, and only getting better as time goes by. Gould discusses many of these in his essays as well.

I urge you to read "Structures of Evolutionary Theory" yourself, it is very readable and interesting. Also, I am surprised to hear that anyone acquainted with PE find it a marginal theory or a minority view. It has held up over time and been supported repeatedly. It is not the only way species appear to change, but it is strongly supported.


Doctor Bashir: "Of all the stories you told me, which were true and which weren't?"
Elim Garak: "My dear Doctor, they're all true"
Doctor Bashir: "Even the lies?"
Elim Garak: "Especially the lies"

This message is a reply to:
 Message 363 by Arphy, posted 10-02-2009 10:21 PM Arphy has taken no action

Replies to this message:
 Message 369 by Dr Jack, posted 10-03-2009 6:06 AM Lithodid-Man has taken no action

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