Question about .cre files and creatures

Hi,

I'm using EEKeeper on my Mac and looking at the creature list, I see for example:

Name: Aasim Resource:ASSIM, <other information>

My question is where is the data for this originate? Is it all stored in a file somewhere? I can't see to find .cre files for AASIM, so I'm guessing that the info is built into the BG:EE Application? Is this correct?

Thanks for any insight,
All the Best
Dave