Wednesday, November 24, 2010

Thoughts on the Evolution of Life on Earth

I recently attended a book discussion of "Ancestor's Tale" by Richard Dawkins.  The book is an excellent discussion of the evolutionary history of life on earth and how different species are related.  As the discussion developed, several people repeated the theme brought up in the book that humankind is NOT in any reasonable sense the "culmination of the evolutionary process". 

Part of the argument for this is that evolution is not directed towards a specific goal.  If you were to replay the tape of evolution starting with just minor changes, it is very unlikely that it would end up producing the human race again.  We are a somewhat random production of evolution.  There is a good argument that evolution would have probably produced some sort of intelligent creatures at some point.  After all, it also produced dolphins, parrots, and squids - three other species that show some signs of developing reasonable intelligence.  Whether it would have produced any species that had the physical ability to grow much larger brains, plus the physical dexterity to manipulate tools easily, and that lived in an ecological niche that was suitable for developing advanced societies similar to humans is an open question.  Perhaps most species that evolve some advanced intelligence end up limited by physical factors from taking that next step of creating advanced technological societies (?)

It occurred to me that we are not the "culmination of the evolutionary process" in a different sense though.  Life has been evolving on Earth for maybe 3.5 billion years.  We are probably only somewhere near the midpoint in the history of life on Earth.  In fact, since evolution appears to be speeding up (both biologically as well as culturally), we are probably still early in the "story of events" in the evolutionary development of life on Earth. 

This is something to think about that perhaps makes you a little more excited and humble at the same time.  It's also an excellent example of what some people refer to as the "feelings of awe and spiritual wonder" produced by a fuller scientific understanding of the universe around us and our place in it.