[Coyoteman]

i have a question for you...how does the author know that those lines on the rock are tally marks and not just the grooves left when someone sharpened a stick or arrow head on that rock?

Stones used for sharpening tend to have more, and deeper scratches, and they are generally more central. Sometimes they have a single deep "V"-shaped groove.

This stone matches the world-wide pattern you find with non-sharpening (i.e., ceremonial, counting, etc.) stones.

Check out a book title "Patterns that Connect: Social Symbolism in Ancient & Tribal Art" by Schuster and Carpenter for illustrations.

[blam]

"Stones used for sharpening tend to have more, and deeper scratches, and they are generally more central. Sometimes they have a single deep "V"-shaped groove."

Whew! I was hoping you'd step forward and answer that one, lol.