I've actually read Elizabeth Marshall Thomas' book. She was your classic Cambridge eccentric. She kept a house full of work dogs, mostly sled dogs, and would take them for walks around the city. That was during the day.
She discovered that the alpha male would get loose at night, and she wondered where he went. So she started following him in his travels in the wee hours (that's the chapter Dave Barry summarizes:) This dog could cross busy highways without getting hurt, once even got as far as Concord, quite a trek from Cambridge (10 mi+).
What was really unusual is that she didn't train her dogs, just allowed them to live according to their own instinctive wolfpack rules, and recorded their behavior.
A fascinating read.
Which sums up Dave's summary.