They "follow the Leader" who just goes in some direction.
Actually such herd animals usually have a hierachy of many 'leaders'. You can see it in films of a moving herd, every now and the a group of animals separate from the herd and go their own way for a while, then the go back into the herd because their sub-leader leads them there.
The leaders of herbivores are the oldest matriarchs. They know where the best grazing and water is in each season and during droughts and floods. They know the entire terrain; the best places of shelter from the elements and the best routes of escape from predators. The males do not lead: young males have no special role; the sire defends against adult bachelor males attempting to usurp their position, and will also often chase off and/or fight predators, especially single ones.
This post was edited by Benedict Arnold at December 5, 2016 10:24 AM MST