These were by far the bones of the Nephilim, the Anunnaki/human hybrid beings, who were much larger than contemporary humans, and that tall stature persisted in the bloodline for an extended period of time and is much less true today, although there continue to be some forced matings with human females as a kind of ritual. There are many ritual acts of inflicted pain and suffering on humans that continue, including the use of humans as food by the Anunnaki and Reptilians, also.
The killing of Anunnaki, and the Nephilim as well, has been a persistent risk factor, and it is owing to the unruly nature of humans and their unpredictability, that has finally caused the Anunnaki to remain in the background, and other species of extraterrestrials as well, for safety reasons. Because they view human beings with disdain and consider them lowly, in being an inferior species, with their arrogance and pride it is unthinkable for them to die at the hands of a lowly human. Being shallow and self-serving, they are also cowards who fear their personal destruction, because they only think about themselves, and this inevitably means they are basically on their own, not being able to count on their fellows for support as they live in a highly competitive hierarchy reinforced through brutality.
Because the Nephilim, who are hybrids of Anunnaki/human mating, remain on the planet and are forced to live among humans, there are many more instances of them being killed as well as succumbing to physical maladies and accidents, and they may not always have access to the most advanced lifesaving measures enjoyed by the full-blood Anunnaki. Even among the Nephilim, they jealously guard the secrets of their longevity gained through hard-won genetic research to find ways to repair almost anything that goes wrong with the body, and that is the reason for their tremendous lifespan. So accidents and homicide, either at the hands of humans, or one another, or the Nephilim, account for the appearance from time to time of full-blood Anunnaki skeletal remains.
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