They can break off, not sure about the down sizing. If I remember right, it went something along the lines of... nub to 1/2 an inch (and notched feathers, short beard) = jake (one yr. old). @5/8" - @3/4" = 2 yr. old. @7/8" - 1 1/8" = 3 yr. old. More than 1 1/4" plus = grand daddy. 1 1/2" plus = Freakin old.