To me it is quite interesting that in every major ancient culture, Greek, Roman, Chinese, Egyptian, etc. has countless stories of dragons. Now, I will concede, that it is slightly conceivable that these stories could have all been based on a single, original mythological dragon story, and that none of these civilizations actually saw a dragon. However, I will also strongly assert that it appears to me much more likely that all of these stories were at least based on fact. Consider the small differences between the shape and appearance of dragons of the different cultures; consider the lack of communication to distribute such a story from civilization to civilization; consider the lack of evidence of any such story; consider the isolation of societies from one another; consider language barriers. A variety of practical difficulties would hinder such a story from having such widespread acceptance and reproduction.
It is also interesting to note the attitude with which these societies treated dragons. The Chinese, known for being a very civilized society, conducted studies on dragons, wrote about them, and philosophized about them as if they were common animals to the people. In fact, this almost scientific attitude towards dragons was common to many cultures world wide2.
Consider the common plot of stories about dragons: Way off from the city, in a remote location, a dragon nests in his lair. From time to time, he invades the city, killing and causing havoc. The people of the city live in a state of fear until a hero can come and destroy the dragon. Now consider an alternate version of this story: A civilization starts to encroach on a dinosaur's territory. The dinosaur, threatened by this action and starving for some food, comes to the city to try to city to protect his territory and hunt. The people eventually get tired of these attacks, and set out to kill the dinosaur. Eventually they do. One cannot help notice the striking paralellisms between these two stories, and if nothing else, can agree that if dinosaurs had lived at the same time as humans, events such as the ones described in dragon stories would be common.
The Chinese calendar is another source in support of this dragon theory. If you are unfamiliar with the Chinese calendar system, this is how it works: It runs on a 12 year cycle, where each year is named for a certain animal. These 12 animals are the rat, ox, tiger, rabbit, dragon, snake, horse, sheep, monkey, rooster, dog, and boar. You will notice, that with the exception of the dragon, all of these animals exist today, and are known to have existed when the calendar was made, in 2600 BC3. Now, how likely is it that Emperor Huang Ti, when creating this calendar, would chose to name 11 years in the cycle after actual animals, and then name 1 after a completely fictitious creature? It goes without saying that this decision would not make sense. There are plenty of other animals, with associated similarly with power and strength, such as the lion or the bear, that could have been used in this cycle. However, dragon remains.
| Note: In order to address the notion that the Chinese Calendar could be named for an animal such as a Komodo Dragon, here's a couple examples of how the Chinese represent the dragon in their Calendar. This makes it clear that they are in fact referring to "mythological" dragons. |   |