Animals dig subterranean dens to remain warm or cool. Some domestic dogs "dig" carpet spots.
Digging for food is another impulse. Our wild companions enjoy tug-of-war over tasty roots in fertile soil.
Huskies, Chows, Malamutes, and other cold-weather Spitz-type dogs are noted for this.
Breeding makes some dogs diggers. Southern farmers created "Feist" terriers to hunt tiny game like gophers and weasels.
A good "ratter" will dig into animal burrows and tunnels to obtain prey.
True scent hounds like Beagles will dig to escape enclosures to hunt squirrels and foxes.