Snakes Can Hear You Scream, Scientists Say
18:25 GMT 15.02.2023 (Updated: 10:43 GMT 21.04.2023)
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Previously, it was widely held that snakes could not hear sound waves carried through the air in any significant capacity, although some ability was known.
I scream, you scream, we all scream - when we see a snake! According to new research that debunks long-held assumptions about snake senses, the slithery serpents can actually hear you when you scream.
The research, printed in the Public Library of Science’s peer-reviewed publication PLOS ONE on Tuesday, describes numerous snake responses to sound across a range of frequencies that did not produce ground vibrations, which snakes are already known to use to navigate.
“We conducted 304 controlled experiment trials on 19 snakes across five genera in a sound-proof room (4.9 x 4.9 m) at 27ºC, observing the effects of three sounds on individual snake behavior, compared to controls,” the scientists wrote, who were all based in Queensland, Australia. The sounds were played at 85 decibels, or roughly as loud as a person screaming.
At different frequencies, the scientists observed eight different snake behaviors, including body movement, body freezing, head-flicks, tongue-flicks, hissing, periscoping (when a curious snake lifts up to one-third of its body off the ground), head fixation, and dropping of their lower jaw, in response to three sounds.
The responses were highly genus-dependent, with Woma Pythons significantly increasing their movement in response, and Death Adders, Taipans, and Australian Brown Snakes all moving away from the sound. They also noted that Taipans took up defensive postures, while three of the five genera showed a variety of other dispositions.
The python was notably the only nonvenomous snake tested, and the only one not to flee from the sound. The Death Adder, an ambush predator, also showed inferior hearing ability to the Taipans and Australian Brown Snakes, both of which are active hunters.
“Our results highlight potential heritable behavioral responses of snakes to sound, clustered within genera,” they concluded. “Our study illustrates the behavioral variability among different snake genera, and across sound frequencies, which contributes to our limited understanding of hearing and behavior in snakes.”
Snakes don’t have external ears like humans do, but they do possess all the internal workings of an ear, allowing them to feel vibrations in their skull and make sense of them. The experiment proves that this doesn’t just help them feel ground vibrations, it lets them detect some sounds traveling through the air, too.
