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Post by schnautzr on Oct 12, 2009 7:01:19 GMT
Not sure whether I mentioned it before, but I see synapsids as the predecessors to all warm-blooded creatures, especially dinos and mammals. However, I am not well-educated on that subject, so I won't debate it without doing further research.
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mantooth02
Researcher
Dieter the Saurornitholestes [F4:ManTooth02]
Posts: 134
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Post by mantooth02 on Oct 12, 2009 16:12:34 GMT
The short explanation is that Synapsids are defined by having a single opening called the (temporal fenestra) on their skull behind each eye. They include mammals and all the mammal-like reptiles. Dimetrodon is in fact a Synapsid and not a reptile at all, might was to fix that fossil creature of the day. Reptiles, including dinosaurs and birds are Diapsids, a sub-class of Sauropsida and unlike Synapsids have two openings on each side of their skull.
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Post by schnautzr on Oct 13, 2009 6:27:31 GMT
"mammal-like reptile"...sounds like a reptile to me. Oh, well, it's Rutiodon Day now. lol
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mantooth02
Researcher
Dieter the Saurornitholestes [F4:ManTooth02]
Posts: 134
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Post by mantooth02 on Oct 13, 2009 20:24:54 GMT
"mammal-like reptile"...sounds like a reptile to me. Oh, well, it's Rutiodon Day now. lol Yeah, but they aren't.
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Post by jadeelf on Oct 13, 2009 21:52:30 GMT
Synapsids were reptiles, but a group unrelated to the Archosaurs (ie dinos, crocs pterosaurs, and birds) Synapsids were the first reptiles to gain control of their metabolic rate (ie warm blooded)and are the ancestors of mammals. Turtles belong to another unrelated group the Testudines. other living reptiles belong to yet another group, Squamata snakes and lizards, and the Tuatara the only living member of it's group the Rhynchocephalia most of which died out millions of years ago.
Warm bloodedness alone doesn't prove how creatures are or aren't related. Dinosaurs and pterosaurs clearly share a ancestor in common, and birds seem to descend from dinosaurs. but it seems that a warm blooded metabolism has evolved independently for Synpasids and Archosaurs. Take the great white shark for instance. its a fish from a primitive family of fish at that, yet it was recently discovered to have a warm blooded metabolism.
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Post by schnautzr on Oct 14, 2009 2:10:56 GMT
Welcome, JadeElf! Really? I didn't know the great white is warm-blooded! I think I'm cold-blooded...I've got a strange thing going on with my metabolism and body climate regulation.
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mantooth02
Researcher
Dieter the Saurornitholestes [F4:ManTooth02]
Posts: 134
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Post by mantooth02 on Oct 14, 2009 3:22:42 GMT
Synapsids are not reptiles, all reptiles (including Archosaurs) belong to the Sauropsida, an entirely different class of animals from Synapsids. Granted I did say mammal-like reptiles, mostly out of old habit. In truth they were nether reptiles nor mammals. White sharks (and other fishes such as tuna) that are often said to be warm blooded are not warm blooded in the same way mammals and birds are. I wish I could get more in depth but it's late, perhaps tomorrow.
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Post by schnautzr on Oct 14, 2009 5:13:09 GMT
Makes enough sense. Mammal-like reptile, is, according to you, a misnomer. Synapsida, is, after all, a separate class from Sauropsida, ever since the two replaced Reptilia.
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Post by zapo07 on Apr 2, 2010 0:27:49 GMT
basically early species of birds are dinosaurs because Archeopteryx was the link between dinosaurs and birds. Also Archeopteryx was in its own family and class because it was part dinosaur, part bird.
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