Hi All!  Was it a cosmic impact that caused the global cooling period known as the Younger Dryas around 12,800 years ago and decimated Clovis Culture?   Those of you who read CHILDREN OF THE DAWNLAND are already familiar with this fascinating theory.  We used it in the book.  Our child heroes survive, of course!   http://www.sciencedaily.com/releases/2015/07/150727180224.htm