According to New Atlas, rat-eared bats are prey for owls, but owls themselves may avoid bumblebees for fear of being stung. A new study suggests that bats take advantage of this fact to stop the arrival of owls by humming like bumblebees. The study was led by Associate Professor Danielo Russo of the Federal University of Naples II in Italy.
A few years ago, he noticed that when he handled rat ear bats that had been caught in a fog net, those bats produced a buzzing sound similar to bumblebee. At the time, Russo and his colleagues were unsure of the purpose of the behavior. They wondered if this might be a way to pass a warning to other bats in the colony, though they also suspected it might be a means of scaring away predators.
Recently, the team tested the latter theory with 16 captive adult owls. These owls include eight barn owls and eight grey forest owls — four of each species are only caught in the wild, while the other four are kept in captivity.
In a lab setting, the researchers replayed four recordings to the owl. These recordings include the hum of rat ear bats, bees and wasps, and non-hum sounds from bats.
It has been observed that owls tend to move away from the speakers when all the hum is emitted, but in the case of non-hum, they approach. This is especially evident in wild owls, which have more experience of hunting bats and being stung by bumblebees.
According to Russo, this is the first known case of mammals utilizing acoustic Bates mimesis, in which a harmless species evades predators by mimicking the sound of a more dangerous species.
"It's a bit surprising that owls represent the evolutionary pressures that shape bats' vocal behavior in response to unpleasant experiences owls with stinging insects," he said. This is just one of many examples of the beauty of the evolutionary process. ”
A paper on the study was recently published in the journal Contemporary Biology.