Vibrotaxis in slime molds – Exploring a previously unknown positive reaction to vibrational stimuli in Physarum polycephalum

Slime molds rely on diverse sensory mechanisms to navigate and explore their environments. The acellular slime mold Physarum polycephalum has been shown to respond to light, chemicals, gravity, and magnetic fields, but its sensitivity to vibration has only recently been suggested. Here, we tested whether Physarum exhibits positive taxis toward vibration. Using two experimental setups, we exposed plasmodia to vibration motors operating at different frequencies and controlled for possible electromagnetic side effects. Plasmodial spread was quantified by image analysis across quadrants relative to the vibration source. In different setups, Physarum consistently moved toward vibration at 200 Hz, while no attraction was observed when motors were inactive, blocked, or running at 100 Hz or 300 Hz. These results suggest that Physarum polycephalum is capable of vibrotaxis, adding vibration to its repertoire of sensory modalities. The ecological significance of this behavior remains unclear, but vibration may serve as a cue to favorable environmental conditions such as rainfall or fungal growth.