A new dialogue option becomes available when speaking to Tree Father Birch in Oasis. He will then explain to the Lone Wanderer why there are many animals in Oasis and how they are attracted to the sanctuary, though this doesn't have any benefits other than a little backstory of Oasis.
In The Fort, this perk makes it possible to bypass the fight with Antony's dogs to get back Sergeant Teddy by telling him that animals are friendly to the Courier so the dogs will not attack. He will remark that he thought there was something wrong with his dogs, as they usually have to be pulled off new visitors to the Fort, and since the fight would not be fun, he will just give up the bear.
During the main quest You'll Know It When It Happens, the search dog can be taken from the ranger, allowing the player to find the disguised engineer.
After Borous has been given Gabe's bowl and told that Gabe has been put down, this perk gives the option to express understanding of his feelings for the cyberdog.
“Commune with beasts! But only if you're successful and aim your gun at the animal in question; you may wish to check the level of your target first in V.A.T.S. with the Awareness perk. The higher ranks allow you to use more interesting commands, allowing you to chance upon, say, a Yao Guai lair and bringing the beast with you to a nearby Raider camp. At Rank 3, the beast acts a little like a dumber pet, with more control over where you can send it, usually into areas to cause a distraction. Animals are beasts that were naturally occurring before the bombs dropped.”— Fallout 4 Vault Dweller's Survival Guide description
When you successfully pacify an animal, you can give it specific commands
Affecting an animal requires looking down a weapon's sights and pressing the confirm/use button. Success will be indicated with an animation, whereas failure will result in a notification. Once one has made an attempt on an animal, they cannot immediately make a second attempt. One must be within a certain range of the animal to pacify it, while Inciting/Commanding requires an even closer range. This perk affects the following animals (list may not be complete):
At rank 3 of this perk, one may have a rare chance to tame an animal instead of pacifying it. Higher levels of Charisma improve the chance of successfully taming an animal. After an animal has been tamed, it will walk to the player character's camp and will from then on guard the camp. Only one tamed animal may be kept at camp at a time, and tamed animals do not respawn.