Definition of pack mentality in English English dictionary
The tendency for groups of individuals to act together without planned direction
Dogs are born into packs. In the wild, packs are the essential social order. Unlike humans, who use a variety of political processes to determine leadership and rank, dogs sort out their social order by dominance and power. In a wolf pack, there is a Top Dog - a clear leader who is the dominant, Alpha male. He's the Big Dog, with pride of place at the dinner table (well, if wolves had a dinner table!), first in mating, first in decision making for the pack