Here's something which I can't explain. Maybe a reader here can shed some light on it?
Back in 2006 we had three wolf pups at the wolf centre (I became a volunteer after adopting Kenai, mentioned above). They were hand-reared, so were used to people right from the start.
I decided to do a fun experiment, knowing it'd be the only chance I'd get. Nobody else was this daft!
* When they were three months of age, I ran away from them in their enclosure. They chased me, but when I zigzagged away from them they gave up.
* At four months old, I repeated the experiment. This time they followed me even after I zigzagged, before catching up with me (whereupon they licked me profusely).
* At six months old, I did it for the final time. This time the two female wolves ran away from me and vanished behind some trees. The male wolf came straight towards me, staring at me intently. When he reached me, he wrapped himself around my legs, causing me to wobble a bit. As I was working out how to extricate myself, there was an almighty "whomp" from behind as the two females jumped upon me. That knocked me over and I was licked half to death by the happy pups.
To this day, I don't know how they communicated their tactics to one another, although clearly they did somehow. Wild wolves do the same thing, of course, as you'll have seen on those nature programmes where they use the pincer movement to get a bison calf away from the herd. FWIW there was no noise from the wolves beforehand, just the rustling of grass as they executed their manoeuvre.