Curiosity question about some Ubuntu dependencies

Hello.
Well, i have a machine wich i assigned as my personal server. It has ubuntu 9.04 server and firstly i installed WordPress via the package management system (it´s wp 2.7.1 wich comes shipped from the ubuntu repositories). Later on this proved inconvenient and i got the latest 2.8 release wich i installed manually. I purged the old one.
The installation that came with the distro had some dependencies, mostly javascript libraries. They are: libjs-prototype, libjs-scriptaculous, tinymce, libphp-snoopy, libjs-jquery.

All those got wiped when i purged, and my normal wordpress installation seems to be working ok without them, So, my question is: are/were these libraries needed by any worpress installation? What are these libraries for?