Two videos demonstrating the noises queens make.
The new video can be viewed here.
Scientists using highly sensitive vibration detectors have decoded honeybee queens' "tooting and quacking" duets in the hive.
Worker bees make new queens by sealing eggs inside special cells with wax and feeding them royal jelly.
The queens quack when ready to emerge - but if two are free at the same time, they will fight to the death. So when one hatches, its quacks turn to toots, telling the workers to keep the others - still quacking - captive.