Pregnant mesosaur is earliest viviparous reptile - boards.ie
Boards.ie uses cookies. By continuing to browse this site you are agreeing to our use of cookies. Click here to find out more x
Post Reply  
 
Thread Tools Search this Thread
14-03-2012, 21:09   #1
Adam Khor
Moderator
 
Adam Khor's Avatar
 
Join Date: Mar 2011
Posts: 3,267
Pregnant mesosaur is earliest viviparous reptile

Yeah, mesosaur, not mosasaur.



http://www.livescience.com/19044-ear...ive-birth.html

The fossils found in South America push back the origins of live birth in reptiles by 90 million years. Mesosaurs were up to 2 meters long and lived during the Permian- being the earliest marine reptiles known. It kinda makes you wonder why modern day sea reptiles such as turtles, sea iguanas and certain Laticauda sea snakes keep laying eggs to these days. (Ichthyosaurs, plesiosaurs and mosasaurs were all seemingly viviparous).
Adam Khor is offline  
Advertisement
15-03-2012, 22:31   #2
Galvasean
Registered User
 
Galvasean's Avatar
 
Join Date: Sep 2006
Location: Hell's Creek
Posts: 33,213
Send a message via MSN to Galvasean
Quote:
Originally Posted by Adam Khor View Post
Yeah, mesosaur, not mosasaur.
The frustration I felt when I saw a link inserted into the article saying, "Mesosaur: T. rex of the sea"
Galvasean is offline  
Thanks from:
16-03-2012, 14:09   #3
Kess73
Category Moderator
 
Kess73's Avatar
 
Join Date: Aug 2007
Location: Tír na nÓg
Posts: 27,738
Send a message via Yahoo to Kess73
So they found one young mesosaur seperate from any adult, and found the remains of one inside a female.

It could point to them being cannibalistic as easily as them being viviparous, although personally I would lean towards the viviparous theory in the case of large marine reptiles but not with Mesosaurs due to their small size (in relative terms) and the fact their limbs suggest that they mpost likely spent some time on land.

It also possibly begs another question about some of the larger extinct marine reptiles if they were viviparous. Were all of them air breathers? Large marine reptiles nowadays, along with members of the order Crocodilia etc., all are air breathers and all lay eggs.

Last edited by Kess73; 16-03-2012 at 14:12.
Kess73 is offline  
16-03-2012, 17:07   #4
Galvasean
Registered User
 
Galvasean's Avatar
 
Join Date: Sep 2006
Location: Hell's Creek
Posts: 33,213
Send a message via MSN to Galvasean
Quote:
Originally Posted by Kess73 View Post
Were all of them air breathers?
Careful now. bordering on Steve Alten territory
Galvasean is offline  
Thanks from:
16-03-2012, 18:28   #5
Adam Khor
Moderator
 
Adam Khor's Avatar
 
Join Date: Mar 2011
Posts: 3,267
Quote:
Originally Posted by Kess73 View Post
It also possibly begs another question about some of the larger extinct marine reptiles if they were viviparous. Were all of them air breathers?
I'm pretty sure they were all air breathers XD Although, who knows? Some sea snakes can obtain much of their oxygen from water... so maybe mosasaurs, relatives to sea snakes, could do the same? It would be helpful if they were say, waiting in ambush underwater for some unsuspecting prey to swim about... I think there's one kind of mosasaur, the Goronyosaurus, that shows some adaptations hinting at a sit and wait predatory lifestyle...

But I would expect even these mosasaurs to need surfacing on a regular basis, like the sea snakes themselves.

I insist, the question here is, why did prehistoric sea reptiles become viviparous, but sea turtles and sea iguanas did not? I can imagine sea iguanas are not as ancient, so maybe that's the reason, but, sea turtles have been around since the Jurassic... why didn´t they become viviparous or ovoviviparous during all that time?
Adam Khor is offline  
Advertisement
25-04-2012, 19:51   #6
Adam Khor
Moderator
 
Adam Khor's Avatar
 
Join Date: Mar 2011
Posts: 3,267
Nat Geo's article on mesosaurs:

http://news.nationalgeographic.com/n...39_600x450.jpg
Adam Khor is offline  
26-04-2012, 10:19   #7
Capt'n Midnight
00:00
 
Capt'n Midnight's Avatar
 
Join Date: Mar 2003
Posts: 46,666
Quote:
Originally Posted by Kess73 View Post
Were all of them air breathers?
Breathing out their arse more like
Capt'n Midnight is offline  
Post Reply

Quick Reply
Message:
Remove Text Formatting
Bold
Italic
Underline

Insert Image
Wrap [QUOTE] tags around selected text
 
Decrease Size
Increase Size
Please sign up or log in to join the discussion

Thread Tools Search this Thread
Search this Thread:

Advanced Search



Share Tweet