African elephants in Kenya have distinct vocalizations for individuals in their social groups, suggesting that they give each other names. This discovery makes elephants the first non-human animals known to address each other using names. The research highlights the complexity of elephant communication and their ability to keep in touch with specific individuals across a large landscape.

https://www.livescience.com/animals/elephants/elephants-give-each-other-names-the-1st-non-human-animals-to-do-so-study-claims