Another sign of obvious intelligence!!!
I read somewhere how to tell if you have a smart dog:
watch how they react to a fly.
If they don't pay attention to it...not very bright.
If they look and and visually track...average
If they try to catch the fly...smart
If they stalk the fly and plan to catch it and do..very intellegent.
I wonder what you'd call inventing games to amuse themselves? Is there Mensa for dogs??