User blog comment:IamJakuhoRaikoben/Chapter 412: Dance Unto Ishgar, Review./@comment-1776824-20141208183425/@comment-7418318-20141208185247

I have a few possibilities for that:


 * They hid in very remote areas.
 * The ones that found their corpses, found them so late that the bones had already been picked clean and the finders assumed they were ancient bones.
 * The finders were real amateurs and assumed the corpses were of unusually big Wyvern rather than Dragons.
 * They might have dug their own gaves and were killed in them, so that their sons would only have to cover them over with earth after the kill.