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Why are our fingers different lengths? – Betty, age 8, California

Why are our fingers different lengths? – Betty, age 8, California

It was one of those rushed mornings when I was already running late for work. In my hurry to grab my keys and head out the door, I knocked a few things off the counter, scattering loose coins onto the floor.

As I picked up the coins, I noticed I was using different movements to gather everything, and those movements seemed to depend on the different lengths of my fingers. My thumb and index finger pinched together to grab a dime, while my middle finger reached farther to pick up coins that had rolled under the edge of a cabinet. My ring finger and pinky curled inward to hold the coins I had already collected while I reached for more.

These motions really brought home how different fingers have their own job – and how each finger’s varying length plays a big part in what it can do.

Pondering such things is part of my job description: As a biological anthropologist who studies the biomechanics of how people move, I often think about how movement, forces and structure work together to shape the human body.

My morning mishap showed that each of my five fingers seemed to have........

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