Brainless Slime Molds Decide by Fluid Flows, Not Brains

Researchers show that the brainless slime mold Physarum polycephalum makes decisions through mechanical means—rhythmic contractions driving cytoplasmic flows—allowing it to adapt and escape blue-light traps. In experiments with shaped light barriers, the organism followed the longest axis and reconfigured its mass to move, illustrating decentralized, non-neural decision-making and shedding light on how such systems optimize behavior without a nervous system.