Doctor Kaiju wrote:Palaeogirl wrote:
That isn't how classification works. You don't get put into a group because you have or lack certain traits. It's all about evolutionary relationships. Warm blooded archosaurs like dinosaurs (birds included) and pterosaurs are still under the crown group of Sauropsida. Reptilia isn't used anymore because it doesn't have any descriptive qualities, it's an unnatural group that excludes things that should be part of it.
By the same logic the green-blooded skink isn't a reptile because it has green blood when other's don't. Traits don't factor into relationship like we used to think they did. Echidnas, for example, aren't fully warm blooded. They also have sprawling limbs, are not at all expressive (most mammals aren't), lay eggs, and have beady eyes that aren't the average for mammals yet they are still mammals.
I'm not sure what you mean by reptilian eyes, by the way.
Eyes are extremely variable in sauropsids, even moreso than mammals which all have a pretty uniform eye design. Some of them don't even have eyes at all. That aside though, if we discovered a new group of lizards that had the required facial muscles to be as expressive as primates it'd still be a reptile. It's about ancestry rather than traits.
Basically, you're everything that your ancestors were as well as what you currently are. Saying that dinosaurs (birds included once again) aren't sauropsids/reptiles is like saying that whales or bats can't be mammals because they're too different. We're still grouped as mammals even though the first mammals probably weren't fully warm blooded, still layed eggs, had only partially erect limbs, likely retained more lizard-like lips, and a number of other traits you wouldn't consider mammalian.
Since he is supposed to be a Permian relic species I'd wager he's a primitive archosaur of some sort. I'd even go as far as to say that he's a highly derived rausuchian but that'd push his origin a little later in time to the Triassic. He's definitely not a dinosaur.
Fine, if birds are reptiles, by that same logic, so are we. We are all reptiles, as we are all what our ancestors were as well as what we currently are.
http://static.comicvine.com/uploads/sca ... achete.jpg
Another set of reptilian eyes. Note the lack of expression, like all reptiles.
Can't argue with that!
Onward, through the fog... can we agree that Godzilla is not a lizard?
We aren't reptiles because our ancestors weren't reptiles. We're synapsids. The old term mammal-like reptile has been abandoned since it was inaccurate. We share a common ancestor with sauropsids but didn't evolve from any ourselves. Basically amniotes hit a fork in their evolution some time during the Carboniferious where the synapsids went one way and sauropsids became the other. Our ancestors would never be considered reptiles but dinosaurs would be considered reptiles since they evolved from sauropsid ancestors. In all honesty though using sauropsid instead of reptile is better for understanding because reptile has a connotation of slow and cold blooded when they all pretty clearly aren't cold blooded.
Everything on the synapsid side of the graph is a synapsid and not a sauropsid/reptile. The sauropsid branch of the graph contains all the sauropsids and therefore everything that'd be considered a reptile. Since birds do fall under the sauropsid side of the graph they are sauropsids themselves. Since we don't have any true reptile ancestors we aren't considered reptiles. We are reptillomorphs (which sauropsids are too) but not reptiles/sauropsids ourselves.
I think your problem with the new classification system is how much has changed since the old days of Aves, Mammalia, Reptilia, and Amphibia being seperate. Now you don't have awkward situations like "Is Archaeopteryx a bird or reptile". It doesn't have to be one or the other, you're your entire evolutionary history. Groups lead into other groups, some branch out into different directions and don't share ancestry unless you go back far enough. Lots of things that were considered to be amphibians (early tetrapods like Icthyostega) aren't amphibians. Amphibians now refers specifically to animals more closely related to modern salamanders than to any other animals. Crocodiles, being sauropsids, are reptiles. That's why they cannot be considered amphibians but they are amphibious. We don't have amphibian ancestors so we aren't considered amphibians. We are tetrapods. Amphibians split off from tetrapods pretty early into tetrapod history. We descended from tetrapods that did not become amphibians.
No need to be snarky about it, it's just the way things are done now. For clarification and for an example,
Homo sapiens is classified (I'm simplifying a bit) as follows.
Animalia
Chordata
Vertebrata
Teleostomi
Tetrapoda
Reptillomorpha
Amniota
Synapsida
Mammalia
Placentalia
Primates
Hominoidea
Hominidae
Hominini
Homo
sapiens
This means we are animals, chordates, vertebrates, teleostomes, tetrapods, reptillomorphs, amniotes, synapsids, mammals, placental mammals, primates, hominoids, hominids, hominins, and
Homo sapiens.
Like I said before, it isn't about physical traits. True relationships are about evolutionary history, not what you currently look like.
I could see him being an extremely derived amphibian of some sort but I feel like archosaur is just more likely overall. He is obviously amphibious, though, but probably not an amphibian.
In all serious though I doubt they were thinking of him as though he actually fit somewhere in the tree of life. Kaiju relationships are hard to narrow down since they have a number of traits normally only found in some groups. Heisei Godzilla's mammal-like ears come to mind.
But yeah he totally isn't a lizard.
:mechagodzilla: 
