They’re the Guardians of the Galaxy’s most mismatched pair – the trash-talking genetically engineered Rocket Raccoon and the sentient tree-man Groot. It isn’t just that the two are so different in appearance, with Rocket being a bipedal raccoon and Groot being a giant tree – the two have completely different personalities. Rocket is a fast talker with a Joe Pesci-style attitude while Groot generally showcases a laid-back personality and a three-word vocabulary.
Nevertheless, there is an undeniable bond between the two of them – which may extend back to a time before Groot even met Rocket in the comics. Although unexplored in the MCU films, the comics reveal that Groot had a fondness for raccoon-type animals since he was a sapling!
In Guardians of the Galaxy #14 by Brian Michael Bendis and Nick Bradshaw, readers learn that Groot comes from Planet X and is a member of the Flora Colossus alien race of tree-people. Ruled over by the “Arbor Masters,” the Flora Colossus gains generations of knowledge by simply absorbing the Arbor Masters’ “Photonic Knowledge” through photosynthesis with every sunrise. Groot himself comes from an “enobled sap-line” that is considered royalty among his people, and therefore received an even more extensive education.
While the Arbor Masters function as Groot’s monarchs, protectors, and educators, his world also contains several squirrel/raccoon-like “maintenance mammals” who serve as the tree’s caretakers. Although most of the Flora Colossus consider these raccoons lower life forms and servants, Groot displayed an unusual fondness for the creatures who greeted him by name. Groot was horrified, however, when he saw some of his tree-brethren bullying a hapless maintenance mammal.
Leaping to the creature’s defense, Groot attacked one of the bullies and returned the maintenance mammal to its family. His actions earned him the love and respect of several species, including a snake-like creature, sentient mushrooms, and many squirrel/raccoon maintenance mammals. When the bullies attacked again, however, Groot savagely killed them and was exiled from his world as punishment.
Groot explored many worlds and eventually met up with Rocket Raccoon who he formed a close friendship and partnership with. While Groot would find additional friends and partners with the Guardians of the Galaxy, his bond with Rocket remained unique – and was likely influenced by his earlier friendships and rapport with the maintenance mammals on his homeworld.
Although Groot’s comic book origins don’t exactly match up with his MCU Guardians of the Galaxy story, it’s very possible that both Groots had a similar history with small animals. Ironically, in the MCU, this was later reversed when Groot regressed into a Baby Groot and then a Teen Groot who regarded Rocket Raccoon as his father. Considering the maintenance mammals were charged with caring for young saplings, this almost seems inevitable.