Dogs "dig" at the ground or on a bed to create themselves a den. It's also why they turn around before curling up to sleep at times.
Canine moms also create a den for their impending brood up to 24 hours before they give birth. They know before we know.
Is it instinct or a learned behavior?
They say instinct but when you watch moms, they do show the little ones what to do so perhaps it is a little bit of both?
The dawgs had a wonderful day today getting groomed, playing retrieve and doing a hunt and seek game.