Unbound: How Eight Technologies Made Us Human and Brought Our World to the Brink

by Richard L. Currier

The essential mechanism of biological evolution consists of three basic processes. First, each generation inherits the characteristics of its parents through information that is encoded in the genetic material contributed by both mother and father. Second, some of this information is inevitably lost or changed through a largely random process we call “mutation.” Third, most mutations have either no effect on the development of the organism or are harmful or maladaptive, making life more difficult for the individuals whose DNA has been altered. Nevertheless, a very small number of random mutations turn out to be beneficial and help the individual organism adapt more efficiently to its environment. As a result, the more beneficial mutations become increasingly common in a breeding population and—if they are sufficiently adaptive—eventually become the new normal within the breeding population. This is the basic process that produced the ability to walk and run on two legs, use fire, cook food, construct dwellings, fashion clothing, and so on.