Scientists have discovered a species of bat has learned to buzz like hornets to discourage predatory owls from eating them.
It is the first ever case in mammals of what is known as Batesian mimicry, when a harmless species imitates a more dangerous one to afford itself protection.
It is also one of the rare examples of acoustic Batesian mimicry, when an animal imitates the sound of another one to deter predators.
Far more common is morphological mimicry, such as the overfly which resembled a wasp with black and yellow bands and a thin waist.
Scientists discovered the acoustic mimicry by chance when researching greater mouse-eared bats, a species native to Europe.
The team caught the bats – which measure up to 9cm long from head to tail, with a 40cm wingspan – while conducting field research.
Professor Danilo Russo of the University of Naples said: “In Batesian mimicry, a non-armed species imitates an armed one to deter predators. Imagine a bat that has been seized but not killed by the predator. Buzzing might deceive the predator for a fraction of a second—enough to fly away.”
The research was dropped for years
The professor made the discovery after catching bats in mist-netting. He said: “When we handled the bats to take them out of the net or process them, they invariably buzzed like wasps.”
The buzzing seemed to be an unusual distress call and the researchers wondered whether the buzzing was meant to be an evolutionary warning to other bats or to deter predators.
However, their initial questions were put to one side while they pursued other research questions for several years until they designed a careful experiment to test their hypotheses about that buzzing.
They found that the buzzing sounds of the bats were acoustically similar to that of stinging insects, and then they played the sound…
Source : skynews
