Researchers from the University of Queensland have found that snakes can hear sounds without using external ears. The study, published in PLOS ONE, challenges the long-standing belief that snake hearing is limited to sensing ground vibrations only. By testing 19 snakes from five families inside a soundproof chamber, the team sought to observe whether airborne sounds could elicit perceptible responses in these reptiles.
Contrary to the common assumption, the snakes reacted to three different sound stimuli. One of the sounds caused ground tremors, while the remaining two did not. The reactions varied among species, revealing a spectrum of sensitivity and behavioral strategies. Some snakes moved toward the sound source, while others turned away or remained motionless depending on their evolutionary background and ecological niche.
The black-headed python, scientifically classified in the genus Aspidites, showed a tendency to orient toward the source of the noise. In contrast, species such as the taipan (Oxyuranus), the brown snake (Pseudonaja), and particularly the more venomous Acanthophis group, exhibited avoidance behavior when exposed to the same stimuli. This divergence in responses underscores how different lineages have adapted distinct sensory and defensive tactics in their natural habitats.
Scientists interpret these behaviors through the lens of ecological pressures. Nocturnal pythons often face fewer competitors in their hunting grounds, which may contribute to a more exploratory or risk-tolerant approach when detecting potential prey cues. Taipans and related snakes, on the other hand, are more prone to encounters with predators and rivals, leading to a heightened propensity to seek concealment and retreat when uncertain about unfamiliar acoustic signals. This adaptive mix of pursuit and caution helps explain why the same sensory input can provoke opposite actions across species. [Citation: University of Queensland]