doc/devel/aniformat in the source tree contains the description of the .ani file format. The animations consists of mostly independently moving parts. How these frames are cycled is determined by the code, in src/uqm/comm/<race>/<race>c.c. Search for AlienAmbientArray.
You may find that there are actually a few unused frames (such as mouths for the Spathi).
Logged
“When Juffo-Wup is complete when at last there is no Void, no Non when the Creators return then we can finally rest.”