When mariner was a small boy, he had a conversation with his father. Mariner asked him how evolution worked. His father said that evolution was slow and that Nature had a way of always trying to make the body work better. He suggested that, in a zillion years, humans would have only three fingers on each hand because the ring and little finger weren’t used very often. Humans pick up things only with the thumb, forefinger and middle finger. He said that even when we grab something like a jar to open its lid, it’s the middle finger and thumb that do all the work.
Ever since, mariner has watched his fingers work with that thought in mind. It is true that in most circumstances we use only the thumb and two fingers. Of course there are many functions that use the entire hand – typing for example, or making a fist, or holding a wet, wriggly fish. Statistically though, the three fingers get the most action.
Mariner was reminded of this conversation recently when he watched a documentary about the many different cousins humans have in the primate branch of evolution. The Aye-Aye, a small nocturnal creature, has a middle finger that looks like a stick; it is much longer than the other fingers. It is a specialized trick of evolution that gave the Aye-Aye a tool to reach small insects under tree bark.
Mariner is sorry that his father didn’t live long enough to experience smartphones. There’s a good chance in the future that the human hand will merge together the last three fingers into one large pad-like finger. Only the thumb and forefinger will keep knuckles.