The fire breathing, huge ass flying dragons that are discussed here, are just a myth. They never existed and were 'created' becouse of other lizards that wanderd around city's but were hardly seen by ppl.
Story's started circling around and as the decades past the story's slowly transformed into the dragons we know today. Real dragons however are no bigger then the space from your shoulder to your elbow, depending on the species.
There is a documentary on dragons on Animal Planet, Sunday March 20 at 8 PM ET.
A sneak preview can be found here:
http://animal.discovery.com/converge...s/dragons.html