Herding is what many different types of animals do for self-defense.  It is when a group of animals that are all in the same species, join a group, for defense.

Many different types of animals lived in herds like Iguanodon. When juveniles are in a herd, the older and more experienced will protect the young and weak. Herds usaully have very very strong social bonds. But if you disperse the herd, than you have a chance of getting food.