Yes they do. My BP which I got from another party, was only fed by him every 6 weeks. And was really in pretty good shape. Though I can deffinetly tell he has gained considerable weight since I got him almost 2 months ago. Now he get's fed every Monday, and he know's when it is Monday. He acts differently on Mondays then any other day, so I know that he knows its feeding day. I guess he has his schedule figured out.