For birds, understanding neighbourhood gossip about an approaching hawk or brown snake can mean the difference between life or death.
Wild critters are known to listen to each other for clues about lurking predators, effectively eavesdropping on other species' chatter.
The fairy wren, a small Australian songbird, is not born knowing the "languages" of other birds. But it can master the meaning of a few key "words," scientists have explained in a paper published in the journal Current Biology.
"We knew before that some animals can translate the meanings of other species' 'foreign languages,' but we did not know how that 'language learning' came about," said Andrew Radford, a biologist at the University of Bristol and co-author of the study.
Birds have several ways of acquiring life skills. Some knowledge is innate, and some is acquired from direct experience.
Radford and other scientists are exploring a third kind of knowledge: acquiring information from peers.
Bradford and colleagues at Australia National University wandered around the Australian National Botanic Gardens in Canberra with customised "tweeter speakers" affixed to their wrists, looking for solitary fairy wrens.
The scientists first played the birds two unfamiliar recorded sounds. One was the alarm cry of an allopatric chestnut-rumped thornbill. The other was a computer-generated bird sound dubbed "buzz."
On first hearing these sounds, the 16 fairy wrens had no particular reaction.
The scientists then trotted around the park and continued to play customised recordings, attempting to train half the birds to recognise the thornbill's alarm cry as a warning sound, and the other half to recognise the computer-generated "buzz" as a distress call.
After three days, the scientists tested what the birds had learned - and their feathered pupils passed the test.
The two sets of fairy wrens responded to the sound they had been trained on by fleeing for cover, but remained indifferent to the other sound.
It's as though a person who only speaks English had learned that "Achtung" means "attention" or "danger" in German simply by listening to people yell phrases with similar meanings in multiple languages at once.
"Until this study, we had limited knowledge about how an animal learns what calls from other species actually mean," said Christopher Templeton, a biologist at Pacific University in Oregon.
"What this new study does is remove the predator entirely. It shows that these birds can learn to associate new sounds with danger, without having to learn through trial and error," said Templeton.
Australian Associated Press
