Mutation is not ‘random’


Mutation is not ‘random’
Ben Haley 2017
The word ‘random’ gets thrown around as if it explains things. ‘A coin flip is random’. ‘Mutation is random’. But these are woeful explanations, because random only exists over possibilities.

A coin flip comes up heads or tails. It cannot come up ‘1’, ‘empty’, or ‘gold’. Of all the things that can be, the coin flip can only be two things. And so a coin flip is not random. Rather a coin flip is randomly heads or tails.

Mutation too. Like a coin flip, DNA cannot be ‘1’, ‘empty’, or ‘gold’. Unlike a coin flip DNA is not limited to two simple outcomes. Instead, complex and unknown rules guide what’s possible. DNA is restricted to a string of As, Ts, Cs, and Gs. The length stays about the same from parent to child. Only a few As will change to Ts. Sex marries one end of a mother’s strand to the other end of the father’s. Things biologists call transposons and retroviruses jump strands from place to place.

These rules determine what mutations are possible. New ones are discovered each decade. How many undiscovered rules further structure the ‘random’ possible mutations?

And so biology does not evolve ‘randomly’, but through a well structured process which we are only beginning to uncover. Over billions of years, this process has invented a photovoltaic mat that nourishes the earth including a talkative ape who’s often guilty of saying ‘random’ as if it were an explanation - problem solved. Better when this ape focuses on the rules that guide what’s possible and all that’s left to learn.

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