I find it fascinating how there are common archetypeal and story themes that are in every culture spanning thousands of years.
I always look for the common denominator when researching. That's where the real gems and clues lay of our ancient lost history.
There is always a flood /cataclysm story, along with other worldly beings mating with humans . That ultimately always seemed to be the downfall in every story.
Anyone who tried to bring this ancient knowledge throughout history ,was silenced ,killed or socially ostracised. Is another common theme.
The fact that these stories of winged , mermaid, snake , dragons and other animal shape shifting other worldly beings, all transcend every single culture and spanning thousands of years . How they brought arts, culture, mathematics, technology and astronomy to the humans of the world at the time . That is something definitely worth to ponder why ?