This piece has been catching a lot of attention: NPR’s always-engaging “sciencey” correspondent Robert Krulwich explores the implications of a paper published last year reporting what seems like an astonishing finding: blindfolded, no one can walk in a straight line. Ditto for swimming, driving—presumably any form of locomotion. Take away our visual cues, and we unwittingly start walking in circles.
People began noticing the phenomenon long ago, as Krulwich entertainingly relates (and the marvelous animation of Benjamin Arthur brings to life). Some have speculated that one side of the brain takes precedence over the other, or that subtle differences in leg length begin to add up. But Krulwich tells us that according to Jan Soulman, lead author of the study and a researcher at the Max Planck Institute for Biological Cybernetics, no one has offered a satisfactory explanation.
Given that the field is still open, I’ll offer a conjecture: perhaps it’s a leftover reflex from infancy? It would make good evolutionary sense for a crawling infant to go in circles whenever wandering alone in the dark. Rather than evolve an elaborate homing sense, our biology inscribed in us the quickest, most robotic route back to mom: a circle.