Do pets remember?

We are on vacation this week and an interesting question came up:  "Do pets remember?".   We were all wondering if our pets, back in "summer camp" as we call it, think about why they are there and wonder if they will be going back home.

If anyone has read anything about this it would be very interesting to us (and I'm sure others).  We all know that our pets are very happy to see us when we return and I'm certain they get excited as they see the house again and all the familar scents inside.

But I can't help but wonder... do they miss us?  Do they think about where they are?  Do they wonder...