Can A Monkey Have A Pet?

In the spring of 2004, researchers monitoring a population of wild bearded capuchins in a Brazilian woodland saw an infant clinging to Chiquinha, one of the adult female monkeys.

The baby was not a capuchin but a marmoset—a much smaller monkey species.

The researchers dubbed the infant Fortunata.

Chiquinha became Fortunata's primary caretaker until the following summer, when she fell pregnant and another capuchin female, Dendê, began mothering the marmoset.

Fortunata behaved like any other capuchin in the group and was raised with the same level of care as a capuchin infant.

Fortunata traveled and foraged with the monkeys, responded to their alarm calls, and even helped the group mob a snake.

When the young capuchins played with the much smaller marmoset, they adjusted their strength to ensure they wouldn't hurt the smaller monkey.

Fortunata eventually vanished the following spring, when the marmoset was almost an adult.

The researchers who observed Fortunata described the marmoset's childhood as a kind of adoption in a 2006 paper in the https://onlinelibrary.wiley.com/doi/10.1002/ajp.20259">American Journal of Primatology. The marmoset, after all, was taken in as an infant and raised by two different mothers.

Although monkey adoption is common in captivity, it most often occurs between monkeys of the https://link.springer.com/article/10.1007/BF02692318">same species, and occasionally within the same https://pubmed.ncbi.nlm.nih.gov/31964036/">genus.

Fortunata the marmoset was clearly a very different kind of monkey, unable to leap from tree to tree or crack nuts like the others.

And yet not one, but two capuchins cared for Fortunata as if it were their own child.

For a long time, humans have considered ourselves unique in our penchant for forming close social relationships with animals of other species. (I say social relationships to exclude other longterm relationship models, such as the parasitic partnership that can exist between a whale and her https://dailyparasite.blogspot.com/2010/11/november-17-tetrabothrius-sp.html">tapeworm.) But a new review paper published in the journal https://link.springer.com/article/10.1007/s10329-026-01281-0">Primates suggests that human pet-keeping has deeper evolutionary roots among primates.