After changing generations, your animal and their litter mates will travel as a pack. The following commands can be performed while in a pack:
Hold triangle to order an attack. When controlling a pack of predators, your allies will perform a group attack on a nearby animal.
Press triangle for a decoy. When controlling a pack of grazers the ally will fall down, serving as bait for enemies. (If a packmate is accidentally ordered to become a decoy, if it is not killed by predators, it will eventually get up and follow the player again.)
If your animal dies, control will jump to one of its packmates, and so each member of your pack means one more chance at survival. In the case of grazers, control cannot jump to a packmate who has been ordered to serve as a decoy.
Your pack actually requires no feeding. However, if you stand still, and there are sources nearby, they will actively seek out corpses/plants and water to drink and eat from. They cannot fully consume corpses/plants, only the player can do that. If your animals' size is large enough, they will also pick up and carry nonspoiled corpses. They will drop it if a) it becomes spoiled, b) if you go into combat, and c) randomly after a certain amount of time.