They actually have better memory than most people think. For instance, I put 4 RTs on my balcony this summer. I originally made a sleeping space with dirt they could comfortably sleep in. They all started sleeping there each night on my balcony. After that, I added a lot more stuff to the balcony - kiddie pools full of dirt they could enter, more bins with entrances, etc. Each day they walk around and into all the different areas I've added. BUT, each night at bedtime, they go back to the SAME bin they started sleeping in originally. All of them recognize that as their bed. Like clockwork at around 6pm, they all navigate through the maze and go back to this same sleeping area. They could have slept anywhere else on that balcony, but they recognize that as their bed. I think that's pretty cool...