Yeah our male BC was an adoption and I feel like he behaves more like an Aussie than a BC -- e.g. nips and barks at animals instead of the BC stare which is apparently a key difference in their herding behaviour -- and does the same for people. If he's really happy to see you? ... He'll nip a hole in your shirt. Something the female BC has never done.

But he's easier to wear out than her. Frisbee for a half hour and he's done. She's impossible to wear out. And thus you can see why they'd be invaluable on a sheep farm...