Once again you can enlarge the photograph and read the display for yourself. But in summary, these spears were made for hunting. That is not to say there may not have been any clan warfare over the millennia, but generally speaking the clans lived in peace with neighbouring people as each roamed their own lands.
The long spears were usually fashioned out of Tea Tree or Melaleuca and were used for throwing over distance. The short spears were made of more rigid hardwood, possibly Dogwood, and these were used for fishing or spearing prey at close quarters.