Editing Dinosaur (section)

== Things people think are dinosaurs, but are not: ==
Some people think of dinosaur as any large extinct prehistoric reptile and tend to lump a bunch of non dinosaurs into the dinosaur category. These include...

*Pterosaurs: These flying archosaurs had among their ranks the largest flying creatures that ever lived and were the closest clade to dinosaurs, both of which being descended from the Archosaurs, but they are not actually dinosaurs themselves. And anyone who says different needs to be introduced to the K-T asteroid there and then.
**On a similar note crocodiles are also not dinosaurs despite also being descended from the Archosaurs, in fact Crocodilias form the entire second branch of the Archosaur tree and thus they are the closest living relatives to the dinosaurs, including the birds of all things.
*Marine Reptiles: During the Mesozoic era there were a variety of large marine reptiles, including Ichthyosaurs, Plesiosaurs, Pliosaurs, Mosasaurs and various other sea beasties. As these creatures are big, reptillian, and look like dinosaurs, the general public often lumps them in as dinosaurs. In truth these are a number of separate families that took to the sea.
*Synapsids: Before the dinosaurs really took off as the dominant form of life during the late Triassic period, the Synapsids, sometimes known as "mammal-like reptiles" were king. One member of this clade is ''Dimetrodon'' or "that fin-back lizard thing' in the Land Before Time and those sets of dinosaur toys your mom bought you when you were a kid". You can tell they're not dinosaurs (and this is a very loose definition) thanks to an extra opening in the skull behind the eye where jaw muscles attached and later became the Sphenoid bone which sits behind the eyes, specialized teeth including canine teeth, among many other distinguishing traits. As the name suggests these guys became the early mammals which turned into us, in fact put a finger behind your eye and one behind your check bone. If you Squeeze that ridge of bone you feel is your own Sphenoid. It's unknown at what point they began to give birth to live young and lactate, although since fur was an extremely late adaptation its generally thought there was a point where something that looked like a dinosaur had lizard <strike>tits</strike> teats.
*Not Quite Dinosaurs: A bit more obscure, but worth a mention. When dinosaurs showed up on the scene in the Triassic Period, they were not alone. A wide variety of large reptiles emerged and evolved alongside them. Among these were other Archosaurs, which included several close relatives to dinosaurs and creatures more closely related to modern crocodiles such as Postosuchus which had some very dinosaurian features. The Triassic Period ended with an extinction event which did in most of these lineages, leaving the Dinosaurs, Crocodilians and Pterosaurs the last of these big reptiles standing.

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Image:Hatzi.jpg|Quetzalcoatlus, the largest living thing that could ever fly.
Image:Mosasaur.jpg|Mosasaur, a giant predatory monitor lizard from the time when sea monsters were real.
image:Gorgonopsid.jpg|Gorgonopsid, closer to you than a dinosaur but not a relative you'd invite over for tea.
</gallery></center>