Buck - Where did the word come from?

Today in casual speech a dollar may be referred to as a buck.  

This use recalls pioneer days when deerskins,  called bucks and does were sold for amounts ranging from forty cents to four or five dollars.  Bucks were larger and therefore more valuable.  A buck or deerskin was a common standard value among Native Americans.

Today the average price of a deerskin ranges from $3.50 to $10.00 a square foot!