Gecko toe-pads have microscopic hairs that use molecular attractions to help them stick to surfaces—incredible specialized adaptations that allow them to climb sheer faces. Perhaps there’s something special about these human hands that make them ideal for climbing. It’s possible to see visible variations in this sample population, but does that mean peculiar and advantageous hand morphology led the climber to excel at the sport? Or that the repeated use and training noticeably changed the shape of hand muscles? Maybe the environment formed the features of their hands—like time molds a boulder, creating the perfect contours for fingers to hold.