I do not think that there is any such thing as a flying, fire-breathing, giant, scaly creature as exists in mythology. However, I do think that these creatures were probably inspired by something real at one time, and possibly a creature now extinct.
I agree with Fizzy and, moreover, I am a big believer in that the cultures who share a strong connection to the character of the dragon- and allow it so many different features- may have some knowledge that was passed on to them from their ancestors. Who knows what they know that we do not regarding this strange and interesting creature? I fully agree with #3 as well, because the field of cryptozoology (my personal feverishly favorite field of science) continues to discover species that were thought to be merely fantastic. Some examples include the giant squid, the vampire squid, the creatures from the abyss, the giant anaconda, and many more.
Personally, I dream about the day when they say that dragons were once real. But then I think about them not having the magical powers that they have in fairy tales and, well, that part depresses me.
There are plenty of dragons in nature still in existence today. There are:
- dragonfish--specifically the black dragonfish; the unrelated barbeled dragonfish; and the Dragon Goby (aka Violet Goby).
- dragron fruit, or Pitaya, a type of cactus
- dragon herb, a type of terragon
- the Komodo dragon, a monitor lizard found on the island of Komodo in Indonesia
- the Chinese Water Dragon, a type of lizard
- and several types of dragon trees, including the Dragon Spruce, an evergreen; and the Female Dragon, a type of Dracaena.
There are also automobiles, airplanes, boats, rockets, buses and trains manufactured by or named Dragon. There are computer-related items, sports teams, roads, bands, games, books, TV shows and movies, and even a chess move (the Dragon Variation). But are there fire-breathing dragons akin to those slain by the knights of old in MYTHS and LEGENDS, the answer is a resounding NO!
The existence of Dragons cannot be 100% ruled out simply because you can 'never say never'. The posibility of Dragons is the same as the possibility of all other mythical creatues... basilisks, chimera, fairies, werewolves, unicorns, minotaurs, trolls, elves, pixies, leprechauns, hydra, vampires, etc etc etc.
The chance that Dragons exist or existed are no greater than the chance that giants existed, basically zero in practical terms.
Yes. "Dragons" (large fire-breathing reptiles that may or may not have wings and be able to fly) might very well be real. The likelihood that they exist presently on earth is remarkably small.
However, consider that at one time, dinosaurs (large reptiles that did, in some species, have wings and the ability to fly) existed on earth. As for the ability to "breath fire", consider that several species of ants spray formic acid, some cobras spit venom, most spiders generate and secrete silk, octopi spray ink, and a multitude of other animals possess a multitude of other ranged chemical mechanisms for defense and hunting. Now consider that there are chemicals that will ignite upon contact with other chemicals (these are called hypergolics and have actually been used by NASA as fuel).
So what do we have? Proof of large reptiles, some of which could fly. Proof of animals using chemical defense and hunting mechanisms. Proof that chemicals which could legitimately result in spitting fire exist. This is adequate to prove that the existence of animals that fit our traditional concept of "dragon" cannot be categorically impossible. So yes, there IS a POSSIBILITY that "dragons" can be real.