Animals not only communicate with members of their own species; New research shows that communication also plays an important role in how different species cooperate.
In a review published in animal behaviorAn international team of researchers investigated how animals use calls, body movements, visual displays, and other signals to coordinate cross-species cooperation. The findings revealed that animals exchange information in a variety of ways to synchronize their behavior and maintain mutually beneficial partnerships.
Different species can cooperate in an amazing variety of situations. Some birds lead humans to beehives in exchange for access to beeswax. Cleaner fish remove parasites from large reef fish and receive meals in return. Researchers use examples from birds, fish, insects, and mammals to show how communication helps these relationships function and sustain.
How do animals adjust across species?
For successful cooperation, animals must match the timing of their actions to achieve a common goal. This can be particularly difficult when the species involved perceive the world differently.
One example is the Greater Honey Guide Bird (Indicator Indicator), which uses a specialized call to attract humans and guide them to beehives. This bird also responds to human calls. In other cases, warthogs use their unique posture to attract birds and mammals to scavenge.
Lead author and researcher Dr Katie Dunkley from the University of Oxford said: “In the examples we know of, individuals adjust their behavior to access shared resources such as food, or to exchange resources for services such as protection from predators.” “We were particularly interested in how sharing information enables closer cooperation between species.”
Communication helps manage risk
Signals and cues to action do more than just initiate cooperation. It also helps animals identify trusted partners and reduces the risk of exploitation.
Interaction with other species can be beneficial, but it can also be dangerous. Communication allows animals to distinguish between partners who provide genuine services and those who may take advantage of them.
For example, some pretty fish (e.g. Raloid is halved) and shrimp (e.g. Urocaridella sp.) Displaying bright colors and making distinctive movements that signal their role to predatory fish allows for safe cleaning interactions. Similarly, lycaenid butterfly larvae use chemical and vibrational signals that prompt ants to protect rather than eat.
This review also highlights the importance of looking beyond visual signals. Many species rely on information gathered through multiple senses, suggesting that if scientists focus only on what animals can see, they may miss important forms of communication.
Flexible and adaptable signals
Not all communication systems are the same. Some are highly consistent, while others vary depending on location and environmental conditions.
Fish seeking cleaning services often use predictable positions such as headstand or tailstand. In contrast, dolphin fishermen may interpret various dolphin behaviors as cues for when to cast their nets, and these signals may vary by region.
“In some forms of interspecific cooperation, the cues or signals vary depending on the ecological context, the species involved, and whether the signals are inherited or learned,” said lead author Dr van der Wal, a researcher at UCT’s Fitzpatrick Institute of African Ornithology. “This highlights how flexible and adaptable communication between species is.”
How does communication between different species evolve?
The researchers also investigated how communication systems between species develop over time.
Some signals may begin as simple cues, meaning characteristics or behaviors that influence another animal’s response, even if they were not originally intended to convey information. Over generations, these cues can become more specialized signals.
Other communication signals may begin to serve entirely different purposes, such as helping animals care for offspring or resolve conflicts. Eventually, these behaviors will be able to be applied to cooperative interactions between species.
“Studying how information flows between species provides powerful clues to how communication systems arise, change, and sometimes coevolve,” Dr. Dunkley said.
Large-scale collaborative research efforts
This review grew out of an interdisciplinary workshop held in Cambridge in July 2023 that focused on interspecies cooperation. The event was attended by researchers studying a wide range of systems.
The resulting paper includes 58 authors from multiple disciplines, including anthropology, biology, and linguistics. It will also bring together experts who study cross-species animal cooperation, mixed-species interactions, and systems in which humans actively train non-human animals.
What scientists want to learn next
The researchers say this review highlights a promising new direction for studying how communication between species evolves and how these interactions affect ecosystems.
The authors highlight the need for broader studies involving larger animal groups, along with additional experiments aimed at understanding how signals arise, persist, and shape cooperative behavior.
“There is still much to learn about how these systems work and evolve,” Dr van der Wal said. “We look forward to future studies that uncover both these interactions and other forms of interspecific cooperation that have yet to be discovered.”
This study animal behavior The title is “Ecology and evolution of cues and signals in interspecific cooperation in animals.”
