Which Behaviors will automatically trigger ground adaptation?
Motion
/ Locomotion
Behaviors
The Motion and Locomotion behaviors automatically adapts characters to the ground provided all the above-mentionned prerequisites are fullfilled. Unless you want to change ground adaptation parameters, you DO NOT need an Adapt Ground behavior.
Navigation Behavior 
Provided the Terrain related prerequisite is fullfilled, the Navigation behavior automatically adapts the root height of the characters, even if not playing any motion with the Locomotion/Motion behaviors.