Cross-Species Bonds: What Primates’ Friendships Reveal About Pets
Observations like Fortunata, a marmoset raised by capuchins in Brazil, show cross-species caregiving can resemble pet-keeping; a new Primates review catalogs 427 cross-species interactions across 88 primate species and 127 other animals, finding patterns where juveniles play, adults groom, and some bonds persist for weeks or months, challenging strict lines between adoption and abduction and suggesting proto-pet-keeping may have deep evolutionary roots, especially in captivity or human-adjacent environments.