To scare away potential predators, some animals exhibit traits of the deadliest creatures. The Scarlet King Snake, for example, wears a red, black, and yellow striped pattern similar to that of a poisonous coral snake; Harmless species of butterflies display the same beautiful color spots on their wings as their mischievous relatives; The nests of species of Amazonian birds are thought to avoid predation by displaying the movement and bright orange color of the venomous caterpillar.
These evolutionary adaptations are examples of Batesian mimicry—named after the nineteenth-century British naturalist Henry Walter Bates—when harmless species evade predators by mimicking more dangerous species whose hungry enemies are known to avoid.
Most of the cases of Batesian mimicry that have been discovered are visible. By comparison, there are few examples of sound mimicry. “Sound mimicry is rarely documented in nature,” said Leonardo Ancelotto, an ecologist at the University of Naples Federico II.
doctor. Ancillotto and colleagues discovered not only a new case of Batesian acoustic simulation, but also the first documented case between mammals and insects. In their work, published Monday in the journal Current Biology, they report a type of bat that mimics the buzzing sound of stinging insects like wasps to trick owls that might otherwise eat them.
Bats are best known for their use of echolocation to maneuver through the air and locate their prey, but they also use various social calls to communicate with each other.
“We know that sound is very important for bats,” said Gloriana Chaveri, a behavioral ecologist at the University of Costa Rica and author of the study.
Even knowing this, Dr. Schaffy was fascinated by the discovery of onomatopoeia. “This is something really new – they use sound to confuse, to deceive predators,” she said.
About two decades ago, the idea for this research first appeared. Danilo Russo, study co-author and now an ecologist at the University of Naples Federico II, was a graduate student working to create a database of all the echolocation calls of the Italian bat species. When he was dealing with one species in the field, the larger mouse-eared bat, he was shocked by its loud sizzling. But he had to wait years to be able to test the hypothesis that they did so to deter predators.
To test whether these bats actually mimic bumblebees to evade predators, the researchers focused on wasps, bees, and two owl species common in the bats’ geographical range. Wild owls that had likely encountered a stinging insect before and owls that had been raised in captivity were included in the study.
The researchers collected data on how owls behave while playing the sound of a variety of sounds through a speaker. Owls generally turn away from the speaker when they hear any hum, and approach him in response to a social call of an unobtrusive bat. But the response of wild owls was much more pronounced than that of owls raised in captivity, supporting the researchers’ hypothesis that the larger mouse-eared bat adapted to avoid predators by mimicking the sound of stinging insects that their predator was avoiding.
The researchers also discovered after analyzing the sound that owls, given their range of hearing, especially bats and wasps will find a similar sound.
David Bevinig, an evolutionary biologist at the University of North Carolina, Chapel Hill, who was not part of the study, is intrigued by the possibility of adaptation involving species that diverged from their last common ancestor hundreds of millions of years ago.
“Imitation is just a powerful idea in science and evolutionary biology in particular,” he said. “It shows how you can get great mods even between really distant related groups.”
Sean Mullen, an evolutionary biologist at Boston University, who was also not involved in the research, noted potential limitations of the work, including the small number of owls used, and said he would be curious to see if the data supported – more broadly – the hypothesis.
But he was excited to learn more.
“Anytime we can find examples where evolution has led to adaptation, that’s further evidence of how amazing life is,” he said.