Exponential Growth
Evolution applies positive feedback in that the more capable methods resulting from one stage of evolutionary progress are used to create the next stage. As a result, the rate of progress (e.g., the speed, cost-effectiveness, or overall “power”) of an evolutionary process increases exponentially over time.
As a particular evolutionary process (e.g., computation) becomes more effective (e.g., cost effective), greater resources are deployed toward the further progress of that process. This results in a second level of exponential growth (i.e., the rate of exponential growth itself grows exponentially).
The evolution of life forms required billions of years for the first steps (e.g., primitive cells). During the Cambrian explosion, major paradigm shifts took only tens of millions of years. Humanoids developed over a period of millions of years, and Homo sapiens over a period of only hundreds of thousands of years. The first technological steps — sharp edges, fire, the wheel — took tens of thousands of years. In the nineteenth century, we saw more technological change than in the nine centuries preceding it. Then in the first twenty years of the twentieth century, we saw more advancement than in all of the nineteenth century. Computer speed (per unit cost) doubled every three years between 1910 and 1950, doubled every two years between 1950 and 1966, and is now doubling every year.
There are a great many examples of the exponential growth implied by the law of accelerating returns in technologies as varied as DNA sequencing, communication speeds, electronics of all kinds, and even in the rapidly shrinking size of technology.