It turns out that stone-age people developed navigation systems, too. Here is a report of a system used in England using regularly-spaced markers.
On the amusing side, here are some of the pitfalls that can happen when you try to correct a major finding in a scientific journal. The take-home lesson - scientists and journal editors are people, too, and science and scientific journals are subject to the same people problems and groupthink that plague every other organization.
Our pastor shared a story from the Bible at Isaac's graveside ceremony today. I'll just paste it in for you:
And the LORD struck the child that Uriah's wife bare unto David, and it was very sick. David therefore besought God for the child; and David fasted, and went in, and lay all night upon the earth. And the elders of his house arose, and went to him, to raise him up from the earth: but he would not, neither did he eat bread with them. And it came to pass on the seventh day, that the child died. And the servants of David feared to tell him that the child was dead: for they said, Behold, while the child was yet alive, we spake unto him, and he would not hearken unto our voice: how will he then vex himself, if we tell him that the child is dead? But when David saw that his servants whispered, David perceived that the child was dead: therefore David said unto his servants, Is the child dead? And they said, He is dead. Then David arose from the earth, and washed, and anointed himself, and changed his apparel, and came into the house of the LORD, and worshipped: then he came to his own house; and when he required, they set bread before him, and he did eat. Then said his servants unto him, What thing is this that thou hast done? thou didst fast and weep for the child, while it was alive; but when the child was dead, thou didst rise and eat bread. And he said, While the child was yet alive, I fasted and wept: for I said, Who can tell whether GOD will be gracious to me, that the child may live? But now he is dead, wherefore should I fast? can I bring him back again? I shall go to him, but he shall not return to me. (2 Samuel 12:15-23)