Earless worms “hear” their skin

Meanwhile, the lab determined that worms can sense light, even though they have no eyes, and that they have the ability to sense the position of their bodies as they move, known as proprioception.

“There was one basic sensory ability that was missing — auditory sensation or hearing,” Shaw said. “But hearing is different from the other senses found in many other tribes in the animal kingdom. On the other hand, hearing has only been discovered in vertebrates and some arthropods. So we think the vast majority of invertebrate species are not sensitive.”

However, researchers found that C. elegansThe worms responded to airborne sounds at frequencies between 100 Hz and 5 kHz – a wider range than some vertebrates can hear. When a sound was played in this range, the worms quickly moved away from the source of the sound, indicating that they not only heard the sound, but also sensed its source.

The researchers conducted several experiments to ensure that the worms actually responded to sound waves circulating in the air and not to vibrations from the surface they were placed on.

Rather than “feeling” the vibrations through their sense of touch, Shaw believes that worms perceive these sounds because their entire bodies behave like a snail’s cochlea, the fluid-filled spiral organ in the inner ear of vertebrates.