Frenemies of TalkRational:
Nontheist Nexus |  Rants'n'Raves |  Secular Cafe |  Council of Ex-Muslims |  The Skeptical Zone |  rationalia |  Rational Skepticism |  Atheists Today | 
TalkRational  

FAQ Rules Staff List Calendar RSS
Go Back   TalkRational > Discussion > Life Science Discussions

Life Science Discussions Biology, Natural History, etc.

Reply
 
Thread Tools Display Modes
Old 04-25-2012, 01:30 AM   #1788699  /  #1
Bilirubin
YOU HEINOUS TOOL
Bejeweled 2 Champion Adjunct
 
Bilirubin's Avatar
 
Join Date: Feb 2009
Location: SOME GODDAMNED METEOR FLYING AT LIGHT SPEED
Posts: 27,016
Bilirubin
Default Dermal ornament in early tetrapods

New paper in Proceedings B by Janis et al. proposes that the deep dermal ornament seen in many lineages of early tetrapods related not with close dermis-bone integration to prevent desiccation but to help neutralize elevated dissolved blood CO2 related to terrestriality and air respiration. The embargo has been lifted and press reports are available, but the paper is not currently on their site.

Here is one report from the Discover Channel.

Quote:
Janis explained that all birds, mammals and reptiles use rib breathing to ventilate their lungs, enabling oxygen intake and carbon dioxide release. Amphibians cannot do this, but they are small enough that they can use their skin to release CO2. Without such systems, animals could fill up with acid.

“If CO2 builds up in the blood it basically goes into solution with the water: H2O plus CO2 equals H2CO3, carbonic acid,” she said.

Fish can lose CO2 over their gills, but gills only work in water. Early tetrapods faced numerous challenges when they ventured on land, probably enticed by food. It would be like humans suddenly needing to develop an ocean-based existence without the benefit of technology.

Most of the early tetrapods, like Eryops (aka “drawn out face”), were too big to solve their CO2 buildup through simple skin release. Their lungs were not well suited to rapid breathing because, unlike humans or even reptiles, their ribs were immobile.
Well, I'm not entirely convinced by the last bit that their ribs were immobile, and I'm pretty skeptical overall, but it should be an interesting topic for discussion. I'll post a link once the paper goes live (unless SteveF beats me).
__________________
Quote:
Originally Posted by ksen View Post
Also, if you guys think I've been way out of line you can recall me.
Quote:
Originally Posted by the BEST elf View Post
i've always hated "well recall me then" as the only meaningful thing that can be done when a mod does stupid shit. it should not be an all or nothing proposition.
Bilirubin is offline   Reply With Quote topbottom
Old 04-25-2012, 01:37 AM   #1788707  /  #2
teeth!
trollo trollini trollus est
Commissar
 
teeth!'s Avatar
 
Join Date: Mar 2008
Location: talkrationalo trollenda est
Posts: 46,780
teeth!
Default

i have comments to make, but will do so later, because I have evening plans!
__________________
Quote:
Originally Posted by Schneibster View Post
Pro Tip™: I'M A CRAZY OLD BIGOT
Quote:
Originally Posted by Old Dan View Post
I tried [crack] once in September 1990 and it was nasty, it made me think "ew, this must be what bicycle tires taste like."
teeth! is online now   Reply With Quote topbottom
Old 04-25-2012, 02:11 AM   #1788791  /  #3
TestyCalibrate
Someone oughta fix the door
dummy
 
TestyCalibrate's Avatar
 
Join Date: Sep 2008
Location: I've mistaken blueberries for blueberries!
Posts: 20,004
TestyCalibrate
Default

And they won't fit in the margin?
__________________
Cabin fever.
TestyCalibrate is offline   Reply With Quote topbottom
Old 04-25-2012, 05:26 AM   #1789118  /  #4
teeth!
trollo trollini trollus est
Commissar
 
teeth!'s Avatar
 
Join Date: Mar 2008
Location: talkrationalo trollenda est
Posts: 46,780
teeth!
Default

Dunno. I was in a rush to meet a friend when I posted that.

I have to actually collect my thoughts on this subject first though!
__________________
Quote:
Originally Posted by Schneibster View Post
Pro Tip™: I'M A CRAZY OLD BIGOT
Quote:
Originally Posted by Old Dan View Post
I tried [crack] once in September 1990 and it was nasty, it made me think "ew, this must be what bicycle tires taste like."
teeth! is online now   Reply With Quote topbottom
Old 04-25-2012, 05:02 PM   #1789487  /  #5
teeth!
trollo trollini trollus est
Commissar
 
teeth!'s Avatar
 
Join Date: Mar 2008
Location: talkrationalo trollenda est
Posts: 46,780
teeth!
Default

Anyways, the main brunt of this paper is that Christine Janis has some weird ideas about gular pumping in early tetrapods, and this is an extension of that. Better comparative morphology could make this a non-issue.
__________________
Quote:
Originally Posted by Schneibster View Post
Pro Tip™: I'M A CRAZY OLD BIGOT
Quote:
Originally Posted by Old Dan View Post
I tried [crack] once in September 1990 and it was nasty, it made me think "ew, this must be what bicycle tires taste like."
teeth! is online now   Reply With Quote topbottom
Old 04-25-2012, 06:28 PM   #1789576  /  #6
Martin B
CAPS LOCK ON
 
Martin B's Avatar
 
Join Date: Mar 2008
Location: few places long enough.
Posts: 2,203
Martin B
Default

Quote:
Originally Posted by teeth View Post
The paper lacks any sense of theology or geometry.
Martin B is offline   Reply With Quote topbottom
Old 04-25-2012, 07:03 PM   #1789607  /  #7
teeth!
trollo trollini trollus est
Commissar
 
teeth!'s Avatar
 
Join Date: Mar 2008
Location: talkrationalo trollenda est
Posts: 46,780
teeth!
Default

idgi
__________________
Quote:
Originally Posted by Schneibster View Post
Pro Tip™: I'M A CRAZY OLD BIGOT
Quote:
Originally Posted by Old Dan View Post
I tried [crack] once in September 1990 and it was nasty, it made me think "ew, this must be what bicycle tires taste like."
teeth! is online now   Reply With Quote topbottom
Old 05-02-2012, 06:28 PM   #1796394  /  #8
Bilirubin
YOU HEINOUS TOOL
Bejeweled 2 Champion Adjunct
 
Bilirubin's Avatar
 
Join Date: Feb 2009
Location: SOME GODDAMNED METEOR FLYING AT LIGHT SPEED
Posts: 27,016
Bilirubin
Default

Paper is out.

Quote:
Originally Posted by Abstract
The dermal bone sculpture of early, basal tetrapods of the Permo-Carboniferous is unlike the bone surface of any living vertebrate, and its function has long been obscure. Drawing from physiological studies of extant tetrapods, where dermal bone or other calcified tissues aid in regulating acid–base balance relating to hypercapnia (excess blood carbon dioxide) and/or lactate acidosis, we propose a similar function for these sculptured dermal bones in early tetrapods. Unlike the condition in modern reptiles, which experience hypercapnia when submerged in water, these animals would have experienced hypercapnia on land, owing to likely inefficient means of eliminating carbon dioxide. The different patterns of dermal bone sculpture in these tetrapods largely correlates with levels of terrestriality: sculpture is reduced or lost in stem amniotes that likely had the more efficient lung ventilation mode of costal aspiration, and in small-sized stem amphibians that would have been able to use the skin for gas exchange.
__________________
Quote:
Originally Posted by ksen View Post
Also, if you guys think I've been way out of line you can recall me.
Quote:
Originally Posted by the BEST elf View Post
i've always hated "well recall me then" as the only meaningful thing that can be done when a mod does stupid shit. it should not be an all or nothing proposition.
Bilirubin is offline   Reply With Quote topbottom
Old 05-03-2012, 03:44 PM   #1797557  /  #9
Requiescat in pace
Dubstyle.
 
Requiescat in pace's Avatar
 
Join Date: Mar 2009
Location: i forget
Posts: 23,286
Requiescat in pace
Default

Bumping the good stuff.
Requiescat in pace is offline   Reply With Quote topbottom
Reply

  TalkRational > Discussion > Life Science Discussions

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT. The time now is 01:56 PM.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ©2008 - 2014, TalkRational.org