Each year, new insights emerge about the ways animals communicate. Research reveals that elephants greet each other with ear flapping and rumbling sounds, sperm whales modify their clicks based on the context, and even naked mole rats have regional “accents” in their colonies.
Clearly, animal communication is intricate. But does this complexity suggest that one species can learn to understand the signals or “language” of another?
Interestingly, some animals are capable of both understanding and using signals from species beyond their own. However, the mental processes behind this behavior remain largely unexplored.
It’s crucial to remember that although we use the term “language” as a metaphor for interspecies understanding, animals don’t possess languages in the human sense. “Language is a species-specific communication system to humans,” explained Simon W. Townsend, a professor of evolutionary anthropology at the University of Zurich. In studying animal behavior, researchers focus on specific communication traits, like sounds tied to particular meanings, rather than using human-centric terms like “language.”
Birds, especially songbirds, are among the most well-researched animals when it comes to learning from other species. A study on migratory songbirds found that solitary birds might understand the calls of different species along their journey, helping them stay safe and navigate more effectively. “We looked for patterns and non-randomness in the vocalizations,” said Benjamin Van Doren, lead author of the study and assistant professor at the University of Illinois. Their findings supported the idea of communication across species.
This research challenges the previous assumption that songbirds migrate alone. However, the study still doesn’t provide a full understanding of what the birds’ calls actually mean. “It’s logical to suspect that social connections might exist between species,” Van Doren said. “I believe these calls may hold more information than we can currently interpret.”
Learning a “language” goes beyond comprehension—it involves speaking it, too. This is where the fork-tailed drongo (Dicrurus adsimilis), a small black bird from Africa, stands out.
Drongos are known for following other animals in hopes of stealing their food. Thomas Flower, a biology instructor at Capilano University in Canada, studied these birds as they trailed meerkats. He observed that drongos would use their own alarm calls—signals of an approaching predator—to scare the meerkats into hiding, allowing the birds to snatch up any discarded food.
However, this tactic eventually backfires, Flower explained. The meerkats catch on to the drongos’ false alarm calls and stop responding by hiding and dropping food. This is where the drongos demonstrate their cunning. They don’t just recognize the warning calls of other animals—they learn to imitate those calls to their advantage. When their original alarm calls lose effectiveness, they start mimicking alarm calls from other birds or even the meerkats’ own calls. By frequently changing their alarm calls, the drongos keep the meerkats on edge, ensuring a steady food supply.
“They know to mimic the species they’re following,” Flower said. “By doing so, they can maintain their deception.” Drongos also mimic other birds’ alarm calls to steal food from them.
This ability to learn and adapt by copying calls from other species shows that drongos can flexibly learn sounds and apply them strategically. “It demonstrates that animals are open-ended learners,” Flower noted.
Flower is still investigating the cognitive processes behind the drongos’ use of false alarm calls. It’s unclear whether the birds are intentionally deceiving other animals—a sign of complex cognitive abilities—or if they’ve simply learned that repeating certain sounds leads to a meal. “Providing clear experimental evidence of intentional deception is very challenging,” he said.
Flower has not yet observed evidence that young drongos understand they are deceiving other animals when they mimic alarm calls. However, he pointed out that young humans also repeat sounds they don’t fully understand, eventually learning their meanings through trial and error. Although drongos show some characteristics of “language” learning, many questions remain about their cognitive abilities.