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Author Topic:   One Question for Evo-Bashers
mark24
Member (Idle past 3305 days)
Posts: 3857
From: UK
Joined: 12-01-2001


Message 92 of 102 (27973)
12-27-2002 10:23 AM
Reply to: Message 91 by Coragyps
12-27-2002 9:41 AM


Coragyps,

quote:

As I understand it, the newer classifications with a cladistic leaning don't view Reptilia as a valid classification anyway. Crocodiles and pigeons are apparently more closely related than either is to cobras, and we mammals share a common ancestor with all three of them.

Correct, but we have to classify them as something. But we're digressing, since crocodiles, snakes & lizards wouldn't be reptiles either, not just the dinosaurs. I've never been convinced about not being able to name paraphyletic groups. Why can't we call them the paraphyletic class Reptilia? It happens elsewhere, after all.

Here's a related question, are mammals amniotes? Or is the amniote group paraphyletic?

Mark

------------------
Occam's razor is not for shaving with.


This message is a reply to:
 Message 91 by Coragyps, posted 12-27-2002 9:41 AM Coragyps has responded

Replies to this message:
 Message 93 by Coragyps, posted 12-27-2002 11:53 AM mark24 has responded

    
Coragyps
Member
Posts: 5381
From: Snyder, Texas, USA
Joined: 11-12-2002
Member Rating: 8.4


Message 93 of 102 (27974)
12-27-2002 11:53 AM
Reply to: Message 92 by mark24
12-27-2002 10:23 AM


Amniotes, along with modern amphibians, may all be descended from Acanthostega or some similar beast. I don't think that the fossil record is quite complete or detailed enough as yet to say with any authority whether amniotes proper arose once or twice. I'm currently reading Gaining Ground by Jennifer Clack, and that seems to me what she is implying - and she's one of the heavy hitters in the Devonian/Carboniferous paleo game.
This message is a reply to:
 Message 92 by mark24, posted 12-27-2002 10:23 AM mark24 has responded

Replies to this message:
 Message 94 by Mr. Davies, posted 12-27-2002 12:22 PM Coragyps has not yet responded
 Message 96 by mark24, posted 12-27-2002 3:48 PM Coragyps has not yet responded

    
Mr. Davies
Inactive Member


Message 94 of 102 (27975)
12-27-2002 12:22 PM
Reply to: Message 93 by Coragyps
12-27-2002 11:53 AM


snip:
quote:
I don't think that the fossil record is quite complete or detailed enough as yet to say with any authority whether amniotes proper arose once or twice

I can't remember where I saw it, perhaps it was something from Dawkins or Gould, but I seem to recall something about that many different forms may have started over. Of course, it would not be that another amphibian type creature would have given rise to another salamander or frog, but they alternate amphibians would have lived on the land and be born in the water.

My poor example not withstanding, does anybody else recall this type of multiple starts for a myriad of different creatures or did I get it wrong?

------------------
When all else fails, check the manual


This message is a reply to:
 Message 93 by Coragyps, posted 12-27-2002 11:53 AM Coragyps has not yet responded

  
shilohproject
Inactive Member


Message 95 of 102 (27987)
12-27-2002 2:53 PM
Reply to: Message 90 by mark24
12-26-2002 8:43 PM


[QUOTE]Originally posted by mark24:

Why can't their be endotherm members of the reptilian class?

Mark

[/B][/QUOTE]

____________________________________________________________
Mark,
I believe it is simply a matter of definition.
-Shiloh


This message is a reply to:
 Message 90 by mark24, posted 12-26-2002 8:43 PM mark24 has not yet responded

  
mark24
Member (Idle past 3305 days)
Posts: 3857
From: UK
Joined: 12-01-2001


Message 96 of 102 (27989)
12-27-2002 3:48 PM
Reply to: Message 93 by Coragyps
12-27-2002 11:53 AM


quote:
Originally posted by Coragyps:
Amniotes, along with modern amphibians, may all be descended from Acanthostega or some similar beast. I don't think that the fossil record is quite complete or detailed enough as yet to say with any authority whether amniotes proper arose once or twice. I'm currently reading Gaining Ground by Jennifer Clack, and that seems to me what she is implying - and she's one of the heavy hitters in the Devonian/Carboniferous paleo game.

Gaining Ground is sitting on my bookshelf, once Vertebrate Palaeontololy (Benton) is finished, Clacks book is next on my list. It looks pretty exhaustive stuff!

Regardless, that's precisely my meaning, if mammals aren't amniotes, then amniotes don't exist because it is a paraphyletic group, just like reptiles, right? Do you see what I mean? Benton takes care to describe groups as monophyletic or paraphyletic, so I don't see why any cladistician should be offended if we accept that the reptile clade is paraphyletic. What should we call reptiles before birds & mammals diverged, if not reptiles? It seems a silly rule to slavishly follow to refuse to categorise post-bird-divergence reptiles the same as pre-mammal-divergence reptiles. Surely the point of classification is to identify synapomorphies, & group organisms into a nested hierarchy using those traits? If reptiles & basal amniotes possess the same traits, then surely they should be classified similarly, though as I have said, the group should be accepted as being paraphyletic.

Mark

------------------
Occam's razor is not for shaving with.

[This message has been edited by mark24, 12-27-2002]


This message is a reply to:
 Message 93 by Coragyps, posted 12-27-2002 11:53 AM Coragyps has not yet responded

    
shilohproject
Inactive Member


Message 97 of 102 (28411)
01-04-2003 5:28 PM
Reply to: Message 89 by shilohproject
12-26-2002 8:21 PM


[QUOTE]Originally posted by shilohproject:
In addition to my earlier post that all fossils are transitional, I offer three living transitional species: penguins (whose feathers blend into something very much like scales on the back side of the wing), duck-billed platypus (lays eggs, has mammary glands, and a beak), and the polar bear (obviously a regular bear physiologically, but behaviorally very much the aquatic mammel, i.e. earth to sea, bottle-nosed dolphin?).

Can anyone solve the riddle of this mneumonic?
King Phillip Sent Charlie Out For Greek Sandwhiches

Have fun.
-Shiloh [/B][/QUOTE]
-----------------------------------------------------------
Bump.

I'm suprised at the lack of feedback on this last couple of paragraphs. No comments, pro or con?

-Shiloh


This message is a reply to:
 Message 89 by shilohproject, posted 12-26-2002 8:21 PM shilohproject has not yet responded

Replies to this message:
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Coragyps
Member
Posts: 5381
From: Snyder, Texas, USA
Joined: 11-12-2002
Member Rating: 8.4


Message 98 of 102 (28412)
01-04-2003 6:22 PM
Reply to: Message 97 by shilohproject
01-04-2003 5:28 PM


Kingdom, Phylum, ??, Class, Order, Family, Genus, Species.

How about Many Volcanoes Erupt Moldy Jam Sandwiches, Usually Not Palatable?

[This message has been edited by Coragyps, 01-04-2003]


This message is a reply to:
 Message 97 by shilohproject, posted 01-04-2003 5:28 PM shilohproject has not yet responded

Replies to this message:
 Message 99 by mark24, posted 01-04-2003 6:37 PM Coragyps has not yet responded

    
mark24
Member (Idle past 3305 days)
Posts: 3857
From: UK
Joined: 12-01-2001


Message 99 of 102 (28413)
01-04-2003 6:37 PM
Reply to: Message 98 by Coragyps
01-04-2003 6:22 PM


Coragyps,

quote:
Originally posted by Coragyps:
Kingdom, Phylum, ??, Class, Order, Family, Genus, Species.

?? = Subphylum?

quote:

How about Many Volcanoes Erupt Moldy Jam Sandwiches, Usually Not Palatable?

I give up!

Mark

------------------
Occam's razor is not for shaving with.


This message is a reply to:
 Message 98 by Coragyps, posted 01-04-2003 6:22 PM Coragyps has not yet responded

Replies to this message:
 Message 100 by shilohproject, posted 01-04-2003 7:46 PM mark24 has responded
 Message 102 by shilohproject, posted 01-04-2003 7:51 PM mark24 has not yet responded

    
shilohproject
Inactive Member


Message 100 of 102 (28416)
01-04-2003 7:46 PM
Reply to: Message 99 by mark24
01-04-2003 6:37 PM


Sorry. I duplicated this, somehow, in the post below.
-Shiloh

[This message has been edited by shilohproject, 01-04-2003]


This message is a reply to:
 Message 99 by mark24, posted 01-04-2003 6:37 PM mark24 has responded

Replies to this message:
 Message 101 by mark24, posted 01-04-2003 7:49 PM shilohproject has not yet responded

  
mark24
Member (Idle past 3305 days)
Posts: 3857
From: UK
Joined: 12-01-2001


Message 101 of 102 (28417)
01-04-2003 7:49 PM
Reply to: Message 100 by shilohproject
01-04-2003 7:46 PM


Oh yeah, I hate it when I miss the obvious!

------------------
Occam's razor is not for shaving with.


This message is a reply to:
 Message 100 by shilohproject, posted 01-04-2003 7:46 PM shilohproject has not yet responded

    
shilohproject
Inactive Member


Message 102 of 102 (28418)
01-04-2003 7:51 PM
Reply to: Message 99 by mark24
01-04-2003 6:37 PM


quote:
Originally posted by mark24:
Coragyps,

quote:
Originally posted by Coragyps:
Kingdom, Phylum, ??, Class, Order, Family, Genus, Species.

?? = Subphylum?[end quote]
--------------------------------------------------------
Yes, quite correct!
-Shiloh
---------------------------------------------------------

quote:

How about Many Volcanoes Erupt Moldy Jam Sandwiches, Usually Not Palatable?

I give up!

Mark



----------------------------------------------------------
It's the order of the planets from the sun outward:
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto.

Another version is:
My very enlightened mother just served us nine pickles.

-Shiloh


This message is a reply to:
 Message 99 by mark24, posted 01-04-2003 6:37 PM mark24 has not yet responded

  
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