Pet sounds: why birds have much in common with humans

An expert on Australian native species says birds can have empathy, grieve after the death of a partner and form long-term friendships

It is generally quite well-known that kookaburras live in family groups: a bonded male and female, plus a retainer of their offspring. Numbers matter in kookaburra society because a neighbouring tribe may have its eye firmly on the expansion of territory - and may invade a smaller group.

This means the injury and eventual death of one bird - most crucially of one of the parent birds - can have disastrous effects for the remaining group. They could be evicted from their home, which is likely to lead to their death.