I had some version of Animal on our Apple IIe in the 80s, and I'm pretty sure it had the ability to save the tree. I have vague memories of the disk drive whirr

I had some version of Animal on our Apple IIe in the 80s, and I'm pretty sure it had the ability to save the tree. I have vague memories of the disk drive whirring after it asked you to provide a differentiating question. Unfortunately I don't have my later Apple IIGS up and running to prove it. But I did find this BASIC version for Atari computers, from Antic magazine in April 1986. The article specifies: "It's vital to save your computer's knowledge base to disk or tape - this knowledge is what makes the game fun. To save, type [CONTROL] [S] and you'll be prompted for a device to save the file to, and a filename. Cassette users should simply type C: at the prompt. Disk drive owners type D: and then the filename. To LOAD a previously saved knowledge base, press [CONTROL] [L] and respond to the prompt as explained just above." The .BAS file at the end doesn't seem to be a plain-text listing, it's probably a saved Atari file. But viewing it in a hex editor, I see strings in the binary file like "Shall I SAVE this data?" https://www.atarimagazines.com/v4n12/Animal.html https://www.atarimagazines.com/v4n12/Animal.html