Banded mongooses (Mungos mungo) can cooperate with common warthogs (Phacochoerus africanus) by cleaning them, removing ticks and other parasites, while the warthogs provide access to food and safety from predators through their vigilance and presence. Example footage from Queen Elizabeth National Park, Uganda. Credit: Leela Channer.

An international team of researchers has revealed how communication enables co-operation between different animal species.

The review highlights how movements, visual displays, calls, and other behavioural cues and signals help partners co-ordinate interactions and align interests across species boundaries.

From birds guiding humans to bees’ nests in return for access to beeswax, to cleaner fish removing ectoparasites from larger reef fishes in exchange for a meal: co-operation between species occurs across a remarkable range of ecological settings.

By gathering examples from birds, fish, insects and mammals, the authors highlight the diverse ways that animals exchange information to organise their actions and sustain mutually beneficial partnerships.

Active teamwork between species

Co-operation between animal species requires individuals to coordinate the timing of their actions to achieve shared benefits, often across distinct sensory worlds.

For example, the greater honeyguide bird (Indicator indicator) uses specialised calls to guide humans to bees’ nests and responds to human calls in return, while warthogs actively solicit cleaning from bird and mammal cleaners through distinctive body poses.

Dr Katie Dunkley, lead author and researcher at the University of Oxford, said: “From the examples we know, individuals coordinate their actions to access shared resources, like food, or to exchange resources for services, such as protection from predators.

“We were particularly interested in how sharing information allows such close co-ordination between species.”

Balancing benefits and risks

Cues and signals help animals identify co-operative partners, initiate interactions, and ensure they benefit from the partnership.

Because interacting with members of another species can carry risks, communication is also important for avoiding individuals that might exploit them.

For example, some cleaner fish (eg Labroides dimidiatus) and shrimp (eg Urocaridella sp) are brightly coloured and use distinctive body movements to safely clean predatory fish species, while lycaenid butterfly larvae employ chemical and vibrational signals to persuade ants to protect them instead of eating them.

Many species rely on multiple senses to improve communication, and the review suggests that focusing only on obvious visual signals may overlook important ways animals exchange information across species.

Flexible communication

Some signals are stable and predictable, like the head or tail-stand postures of fish seeking cleaning services, while others vary across locations and ecological contexts, such as the dolphin behaviours fishermen interpret as indicators of when to cast their nets.

Senior author Dr Jessica van der Wal, a researcher affiliated with the University of Cape Town’s FitzPatrick Institute of African Ornithology, said: “In some forms of interspecies co-operation, cues and signals vary depending on the ecological context, the species involved, and whether the signal is inherited or learned.

“This highlights just how flexible and adaptable interspecies communication can be.”

Evolution of co-operation across species

The review also explores how communication systems between species may evolve.

Some signals begin as simple cues, features or behaviours that influence how others respond, even though they did not originally evolve for communication. Over time, these cues can develop into clear signals.

Other signals originate as behaviours used in different contexts, such as settling conflicts or caring for young, before being adapted for communication in interspecies co-operation.

Dunkley said: “Studying how information flows between species gives us a powerful window into how communication systems originate, change and sometimes co-evolve.”

Future directions

The review opens new avenues for studying the evolution of communication across species boundaries and the ecological importance of interspecies cooperation.

It also highlights the need for broader studies across taxa and more experimental work to understand how signals emerge, persist and shape cooperative behaviour.

Van der Wal said: “We still have much to learn about how these systems function and evolve.

“We look forward to future research revealing both these interactions and other forms of interspecies co-operation yet to be discovered.”

The review is published in Animal Behaviour.