13
   

What are your eclipse plans?

 
 
Ponderer
 
  1  
Reply Sun 27 Aug, 2017 11:26 pm
@oralloy,
Uh..........huh?
farmerman
 
  2  
Reply Mon 28 Aug, 2017 05:02 am
@oralloy,
1 Your use of (mostly) EU time sequence names( like Cisuralian and Guadelupian) made me smile. Ive been talking North Amreicn age nomenclature and the CGS/ USGS and GSA is about North America.(The ICS system is trying to base itself on Global Boundary Stratotype Sections and Points GSSP), As far as I know, its still a work-in -progress- experiment at making the next steps into "Bar coding" most geo names. So far they have trouble on where to hold meetings.
2. Your defaulting to "I understand that such begat such and such" Is kinda lumping everything together and there are many many new specimens of radiated species of pelycosaurs that provide us with the better roadmap to mammals.Each year we get hundreds of new specie fossils of the Permian alone
While pelycosaurs had some similarites of mammals (like differentiated teeth). there were a whole lot of things they failed to have as we make new finds and make us deal with the most confusing issues of derived structure, that is the various skull openings and from where they derived .
Pelycosaurs were reptiles not protomammals because there were lots of more derived species that rose from taphinocephalids and theriodonts and a new one whose name I cant remember now. pelycosaurs remained in the fossil record until the end of the early TRIASSIC, (mammals were already evolved .
The issue of common ancestry precluded by contemporeneity is pretty much established. We keep opening the evidence pile with more species and it makes the confusion even deeper .(Most of the findings come from hobbyist fossil hunters whose findings may not be classified for decades )
I use these critters for locating strat units in very small time sequences because associated deposits of some specific things I look for occur as a function of a time sequence in which dimetrodons occur. Theyre a tool. When I teach applied strat, I have paleo students as well as applied science geos who will be working for mining rights and we carefully need to separate a dimetrodon from a moschops or a finless thrinaxodon or an evolving kannemeyeria.

Ill beg off the issue based on Steve Stanley's "distribution of lifeforms" My use of "lizard" for dimetrodon is based on the fact of its group name pelycosaur (Bowl lizard) The fact that its group remained till the Triassic also means that youve gotta look more carefully for the real common ancestor of Morganucodon or other "lizard Rats".

The arguments about "what do we call this thing" are kind of old fashioned, biostratigraphy and evolutio n are more interested in derivation and "Finely linking" species.




farmerman
 
  1  
Reply Mon 28 Aug, 2017 05:10 am
@Ponderer,
whenever oralloy and I can get onto a subject we can beat it till it stops breathing and then even then its nit sufficiently dead.

This all started because I called his favorite "paleo reptile" a lizard and he then took offense because it was his favorite fossil critter .

Ya gotta watch yer step in this board. I once called King Kong a MONKEY and tsarsteppan chewed my ass out for improper classification.

Ponderer
 
  1  
Reply Mon 28 Aug, 2017 05:26 am
@farmerman,
I just couldn't see how my comment evolved into his reply. Like I've written before, "On a scale of world problems, it doesn't register."
So was King Kong a dinosaur /ape?
0 Replies
 
Ponderer
 
  1  
Reply Mon 28 Aug, 2017 05:31 am
@farmerman,
Anyway. I plan to get out and wax my car during the next eclipse.
0 Replies
 
Leadfoot
 
  1  
Reply Mon 28 Aug, 2017 08:49 am
@farmerman,
Quote:
"Contemporeneity precludes common ancestry"

But, but, but...what about...
Ponderer
 
  1  
Reply Mon 28 Aug, 2017 02:53 pm
@farmerman,
Well,..........huh?
0 Replies
 
oralloy
 
  1  
Reply Mon 28 Aug, 2017 07:28 pm
@farmerman,
farmerman wrote:
1 Your use of (mostly) EU time sequence names( like Cisuralian and Guadelupian) made me smile. Ive been talking North Amreicn age nomenclature and the CGS/ USGS and GSA is about North America.(The ICS system is trying to base itself on Global Boundary Stratotype Sections and Points GSSP), As far as I know, its still a work-in -progress- experiment at making the next steps into "Bar coding" most geo names. So far they have trouble on where to hold meetings.

I think I copied the names from an ICS website. I remember the divisions of the Permian but not the names, so I just looked up something official and copied the names.


farmerman wrote:
2. Your defaulting to "I understand that such begat such and such" Is kinda lumping everything together and there are many many new specimens of radiated species of pelycosaurs that provide us with the better roadmap to mammals.Each year we get hundreds of new specie fossils of the Permian alone
While pelycosaurs had some similarites of mammals (like differentiated teeth). there were a whole lot of things they failed to have as we make new finds and make us deal with the most confusing issues of derived structure, that is the various skull openings and from where they derived.

They failed to have those features because they are the most primitive of the synapsids.


farmerman wrote:
Pelycosaurs were reptiles not protomammals because there were lots of more derived species that rose from taphinocephalids and theriodonts and a new one whose name I cant remember now.

Reptiles are diapsids. Pelycosaurs are synapsids. That means pelycosaurs cannot have been reptiles.


farmerman wrote:
pelycosaurs remained in the fossil record until the end of the early TRIASSIC, (mammals were already evolved .
The issue of common ancestry precluded by contemporeneity is pretty much established.

I continue to fail to see how that logic is valid. If a few non-mammalian therapsids had managed to survive until modern times, would that be taken as evidence that mammals did not derive from therapsids?


farmerman wrote:
The fact that its group remained till the Triassic also means that youve gotta look more carefully for the real common ancestor of Morganucodon or other "lizard Rats".

I certainly see the merits of finding the common ancestor.

But the essence of the argument that you are presenting is that if a primitive branch survives into a more modern time, that means the more evolved branch had to have split off very early in their history.

I don't see the basis for such a conclusion. Sometimes very primitive forms survive for a very long time simply because they work well. Sharks and crocodiles come to mind. It certainly is possible for a more evolved linage to have split off from a primitive linage early on. But it also seems possible for a more modern species to split off from a primitive form after that primitive form has been around for awhile.

The best way to find when therapsids split off from pelycosaurs is to look at when the very first therapsids first appeared in the record. The split likely happened shortly before that. If pelycosaurs kept surviving in some form after therapsids split off from them, that would not change the date of the split.
0 Replies
 
oralloy
 
  1  
Reply Mon 28 Aug, 2017 07:31 pm
@farmerman,
farmerman wrote:
because it was his favorite fossil critter.

I'm also rather fond of gorgonopsids and Cynognathus. Mammal power!
0 Replies
 
oralloy
 
  1  
Reply Mon 28 Aug, 2017 07:32 pm
@Leadfoot,
Leadfoot wrote:
Quote:
"Contemporeneity precludes common ancestry"

But, but, but...what about...

How can a synapsid be a diapsid?
Leadfoot
 
  1  
Reply Tue 29 Aug, 2017 08:34 am
@oralloy,
I was just wondering how farmer's quote of "Contemporeneity precludes common ancestry" fits with the universally accepted - 'All life has common ancestry'.

I guess it sounds more scientific than "Let the earth bring forth grass, the herb yielding seed, and the fruit tree yielding fruit after his kind, whose seed is in itself, upon the earth: and it was so."

Ok, back to dinosaurs, or eclipses or WTF we were talking about
0 Replies
 
oralloy
 
  0  
Reply Wed 30 Aug, 2017 04:31 pm

July 2, 2019

I'll warn you ahead of time, unless you're a lottery winner, you can't afford this cruise. Nonetheless:

http://www.travelquesttours.com/tours/2019-south-pacific-cruise-to-totality/welcome/

http://eclipse.gsfc.nasa.gov/SEgoogle/SEgoogle2001/SE2019Jul02Tgoogle.html

http://eclipse.gsfc.nasa.gov/SEanimate/SEanimate2001/SE2019Jul02T.GIF
http://eclipsophile.com/wp-content/uploads/2016/09/Figure1.jpg
0 Replies
 
 

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