System of the Pack

Maybe it's just me, but it used to be rare to hear any references to the concept of dog pack.  Then, on one of the cable channels (National Geographic) we started to hear about the work of Cesar Millan, AKA "the Dog Whisperer".  In his amazing work, he takes the point of view of dogs, and makes the case that whenever there is a problem dog, the real problem is with the humans that the dog relates to.  In the course of this, he uses the idea of the pack a lot.

A pack (of wolves, of dogs) is a natural system, as is the school (of fish), flock (of birds), pod (of whales), etc.

The pack has definitely come into common use, to describe, among other things, a human household that includes dogs as members.