The hidden social lives of fairy-wrens are just as complex as those of animals with much larger brains, including monkeys, whales and even humans.
Corvids and parrots might be the superstars of the bird world - but other species like gulls, geese and even chicken have shown some impressive skills too.
From choosing a compatible personality to sharing childcare equally, many Australian birds have mastered the art of successful relationships.
The natural world is full of intriguing clues.
Magpies have such good hearing, they can hear the very faint sound of grass roots being chewed.