Although snakes do not have external ears and a middle ear, they are not deaf. But how snakes naturally respond to sound is still unclear.

A University of Queensland-led study found that snakes can hear and respond to both airborne sound and ground vibrations.

Scientists conducted 304 controlled experiments on 19 snakes of five sexes in a soundproof room. They observed the effects of three sounds on the behavior of individual snakes compared to controls.

The study is the first of its kind to use unanesthetized, free-moving tubes. It found that the snakes respond to sound waves traveling through the air and possibly human voices.

Dr. Christina Zdenek from UQ’s School of Biological Sciences said: “We played one sound that caused ground tremors, while the other two were airborne alone. It meant we could test both types of ‘hearing’: tactile hearing through the snake’s ventral scales and airborne through their inner ear.’”

“The responses depended heavily on the sex of the snakes.”

“Only the woma python tended to move towards the sound, while taipans, brown snakes and especially death adders all moved more away from it.”

“The behavioral responses also differed, with taipans in particular showing more defensive and cautious responses to sound.”

“The different responses are probably the result of evolutionary pressures over millions of years designed to aid in survival and reproduction. Woma pythons, for example, are large nocturnal snakes with fewer predators than smaller species and probably don’t need to be as careful, so they had tendency to approach the sound.

“But taipans may need to worry about raptor predators, and they also actively hunt their prey, so their senses seem to be much more sensitive.”

“The findings challenge the assumption that snakes cannot hear sound, such as humans talking or screaming, and could change the view of how they respond to sound.”

“We know very little about how most snake species navigate situations and landscapes around the world. But our research shows that sound can be an important part of their sensory repertoire.”

“Snakes are very fragile, shy creatures that usually hide, and we still have so much to learn about them.”

Magazine reference:

  1. Christina N. Zdenek et al. Sound garden: How snakes respond to sounds in the air and on the ground. PLOS ONE. DOI: 10.1371/journal.pone.0281285