Honeyeaters use badgers to break beehives (Image: Bruce Beehler/CI)
By Finlo Rohrer and Tom Geoghegan
BBC News Magazine
A dolphin appeared to "talk" to two stranded whales before leading them to safety. How common is inter-species communication?
Before the bottlenose dolphin turned up, the beached pygmy sperm whales were in clear distress.
But when Moko arrived at Mahia beach on the east coast of New Zealand's North Island, their mood changed and they followed him to safety.
The ability of some animals to communicate is well known.
And while many mammals have the ability to understand human language, they lack the capacity to articulate anything themselves, although apes have been known to use hand gestures.
What's less well documented is the communication between species.
Justin Gregg, vice president of the Dolphin Communication Project, said it is possible that a bottle nose dolphin and a pygmy sperm whale could communicate in some way.
"But it wouldn't be instructions like 'hey buddy the open ocean is over here follow me'," he says.
Dolphins use three forms of signalling to other dolphins - whistles, clicking and postures.
Different dolphin species do use similar types of signal
Dolphin Communication Project
Dolphin rescues whales
Similar in size and colour to a bottlenose dolphin, it is possible that a pygmy sperm whale might have signals in common with a dolphin, just as different species of dolphins are known to share signals which might theoretically allow a form of basic inter-species communication.
But just as it's possible that Moko the dolphin and the stranded whales shared a signal, it is also possible that the whales just saw a vaguely similar creature and followed it.
And it is important to recognise that the dolphin was not giving detailed instructions in a form we recognise as language, says Mr Gregg.
It is no longer thought dolphins have a language that can be decoded, they simply use a complicated communication system, like elephants or ants.
There have been some other recent examples of inter-species communication. A few weeks ago, viewers of the BBC's In Cold Blood saw a gecko "beg" a sap-sucking insect for food.
There are many reasons why different species communicate, say Vincent Janik, lecturer at the Sea Mammal Research Unit at St Andrew's University.
"The animals exploit the systems of others for their own benefits. Sometimes the benefits are the same for each, therefore they share information.
"Sometimes they are trying to take advantage of the other. Getting food may not be to the advantage of the one giving up the food."
Ants protect the habitat of leaf lice and in return get a sugar excretion to eat, he says. They interact chemically and physically - the ants massage the leaf lice by secreting a small amount of the sugary food they are after.
And honeyeater birds guide larger animals, like badgers, to a beehive for them to do the "dirty work" of breaking it so they can gain access.
The communication takes the form of the honeyeater flying around the badger to get its attention then performing a call, flying towards the beehive and checking the badger is following. If it isn't, the honeyeater flies back to try again.
It's a mechanism that's relatively automatic, it's not about forming a plan
Sea Mammal Research Unit
Good animal communicators
Communication is often just one-way and completely inadvertent, says Mr Janik.
"The vervet monkey listens to the alarm calls of the superb starling to find out what kind of predators are around.
"Then the monkey follows an avoidance strategy accordingly, so if it's an aerial predator they duck under trees or if it's a leopard they run up trees. This way they improve their chances of survival." Inter-species communication most commonly takes the form of eavesdropping but it is not something that should be assessed in human terms, he says, because it's not done consciously. "It's a mechanism that's relatively automatic, it's not about forming a plan. The animal is trying to optimise its own survival chances and extracting the best possible information."
BBC NEWS | Magazine | Can different species 'talk'?