[CherryBrandy]

I am going to go out on a limb here - molluscs don't think.

However, Tortoises definitely do a degree of thinking but a lot is instinct I agree. Papa Un will stop to look over a ledge and I would imagine be deciding whether to walk over the edge or not. He doesn't - is that because he thinks it is too steep for him. Others nose plant it. Elenor will look up from her enclosure when I come into the room. She follows me round with her eyes. What's she thinking I wonder? But her actions are to follow me. Sometimes she walks over a little bit but when her view is obscured she goes back to the spot where she was and looks up again. CB