Introducing co-cultures: When co-habiting animal species share culture

Cooperative hunting, resource sharing, and using the same signals to communicate the same information—these are all examples of cultural sharing that have been observed between distinct animal species. In an opinion piece published June 19 in the journal Trends in Ecology & Evolution, researchers introduce the term "co-culture" to describe cultural sharing between animal species. These relationships are mutual and go beyond one species watching and mimicking another species' behavior—in co-cultures, both species influence each other in substantial ways.

"Co-culture challenges the notion of species-specific culture, underscoring the complexity and interconnectedness of human and animal societies, and between animal societies," write the authors, behavioral ecologist Cédric Sueur of the Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg-CNRS, and the Institut Universitaire de France and primatologist Michael Huffman of Kyoto University and Nagasaki University.

"These cross-species interactions result in behavioral adaptations and preferences that are not just incidental but represent a form of convergent evolution."

Co-cultures have been observed between humans and nonhuman animals—for example, between humans and honeyguides in Tanzania and Mozambique, where the birds lead humans to honeybee nests. They are also evident between different species of nonhuman animals—for example, cooperative scavenging between ravens and wolves, cooperative hunting between false killer whales and bottlenose dolphins, and signal sharing between distinct species of tamarin. Ultimately, this inter-species sharing of culture could drive evolution, the researchers say.

"Cultural behaviors that enhance survival or reproductive success in a particular setting can lead to changes in population habits that, over time, could drive genetic selection," they write.

To extend our understanding of co-cultures, the researchers say that future studies could start by investigating wild animals in urban environments.

"Urban animals modify their behaviors, learning, and problem-solving skills to cope with urban challenges, reflecting a dynamic response to urban landscapes," they write. "Similarly, humans alter their urban spaces, influencing wildlife behavior and evolution. This reciprocal adaptation between humans and wildlife is fundamental to understanding co-culture."

Future research is also needed to examine the possibility of cultural and genetic co-evolution—the idea that species' cultures and genomes are evolving in concert. A key question, the researchers say, is "In the context of co-culture, how do cultural adaptations influence genetic evolution, and vice versa, across different species and environments?"