This Tokeh gecko’s bright golden eye is so mesmerizing that it almost distracts from another special detail: the ear opening on the left of the picture. In fact, geckos are one of the few reptiles with recognizable outer ears, but an even greater sensory wonder lies in the inner ear.
As Dawei Han and Catherine Carr from the University of Maryland have discovered, unlike humans, for example, geckos can also perceive low-frequency vibrations between 50 and 200 Hertz with their inner ear.
The geckos apparently achieve this vibration hearing with the help of their small atrial sac (sacculus) – part of the balance organ in the inner ear.
The discovery of this new sense could revolutionize the understanding of reptile sensory perception and communication skills. Until now, many species of reptiles were considered deaf and mute simply because, unlike geckos, they do not have external ears and therefore cannot perceive airborne sound waves. However, the geckos’ “sixth sense” now suggests that other reptile species also have a similar signaling pathway in the inner ear and may even communicate using vibration signals.
The research results could also provide new information about the evolution of the sense of hearing. It is already known that fish and amphibians also sense vibrations with their saccule, but the fact that this ability has now also been demonstrated in a reptile suggests that the development of the sense of hearing was much more complex than previously thought.