The subject comes up from time to time, but it's probably difficult to use the onsite search engine while Mudcat is flopping about between different locations, so a new thread on an old topic is understandable. You need to distinguish between tunes that have been around for a long time in use and tunes that have been resurrected from long ago. The former count as "survivals", while the latter are just archaeological specimens; fossils which are interesting but dead.