The thing to understand about life is that environmental conditions are always changing and all creatures have to adapt to these changing conditions else they suffer or even die. I am discovering that this is just as true for extraterrestrial beings with advanced technology, as it is for us the indigenous human species of earth. Retired Air Force Airman Charles Hall has written extensively about a species of human extraterrestrial called the Tall Whites who occupy and maintain a base in the mountains now encompassed by Nellis AFB. (Search: Charles Hall Tall Whites)
Introduction: http://www.ufodigest.com/article/new-exopolitics-book-introduction
Chapter One: http://www.ufodigest.com/article/evolution-other-worlds
Charles has also has told me personally that the extraterrestrial species know as the Greys occupy and maintain a base larger than the TW base at Area 55 that is also on Nellis, while a very human type of ET with 24 teeth have a base near a fiord in Norway. Charles claims to have met all three types in his life. Nellis is the home of the world renown Area 51 that is now part of global popular culture.
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