It would be great if there was a way to list the different commands in mothur that could generate a particular file extension. It would follow that you can look at all the extensions of a file and at least have some ideas of the commands used to generate that file (or remind you which commands you used that generated that file). Some are obvious since similar to command (e.g. .dist) or intuitive (e.g. .tax), but what command generated “.an,” for example? Sorry if this is an old idea and an index exists somewhere…just haven’t found it yet.