There is no history that's been recorded that the dragons weren't actually living beside us. No one, dragon or human alike, can pin point either's origin on the planet's timeline. It's a not so well kept secret, but pinned on other wildlife. The dragons evolved to emit certain wavelengths in light that humans can't see. They've always been there...
The dragons taught early man how to use tools. The dragons ensured kids made it to adulthood to reproduce in exchange for some of their food and peace. They were never hunted and treated with the utmost respect. They took their duty seriously.
Humankind only made it so far because of the secret help from creatures they stopped being able to see several millions of years ago. There was a clan of dragons that lived in the sky, a clan in the forests, a clan in the deserts, and the more dangerous clan that lived in the shadows. Most dragons lived by unspoken laws to never harm humans, but the shadow clans felt everyone and everything was fair game. Most clans had to deal with their own rebellious shadow clan incidents.
It always seemed unfair. There would be another war. The old dragon watched as a human put fire near an egg. She didn't have a chance to tell the youngin that the human didn't see the egg nor would that fire hurt it.
The young female had assumed the human would hurt the egg. She was always a bad egg acting without thinking. The old dragon didn't have the strength to stop a hormonal youngin'. She'll be put to work for the rest of her life watching over that human's family.
The elder watched never intervening. The human most likely died quickly. After the most horrible disaster in dragon history involving a hormonal new mom.
