The arrow of evolution

Scientific discoveries indicate that life evolved on earth  starting from  a single cell and emerged into the life (nature)  in which we exist. Yet what was it evolving to?  Is it more complex than before? Or  is there more life today than before? What is the measure of this evolution?  At one time it seemed as if life evolves from the smaller to the bigger until the dinosaurs disappeared. The human is obviously more complex than a bacterium, nevertheless unicellular organisms contribute significantly to the earth biomass.  Since they have obviously “evolved less”  than us why are they still with us? Shouldn’t they be replaced by the “more evolved”?   Other disturbing thoughts were published here previously

Let’s turn to a remarkable book , “The phenomenon of Life” by Hans Jonas (1),  for some new ideas on this issue. Throughout evolution the higher depends on the lower.  The “fittest”  may  still survive as Neo-Darwinists claim, but depends more and more on the lower. According to Jonas:” {There is a] dependence of each higher on the lower, [and a] retention of the lower in the higher.

Life evolves within food chains. A food chain is defined as:  A succession of organisms in an ecological community that constitutes a continuation of food energy from one organism to another as each consumes a lower member and in turn is preyed upon by a higher member. ( At the origin of the food chain are algae, cyanobacteria and plants, which polymerize organic matter   from inorganic molecules. Initially food chains consisted of  cyanobacteria. Then came algae and finally the plants. They paved the way for other organisms which depend solely on organic matter.  This is why evolution retains a  “Dependence of each higher on the lower”. Life (us) cannot exist without the lower. 

The food chain may be regarded as an elementary process in a super organism called Gaia, which is the set of all food chains on earth. Gaia is a web of food chains. It is Gaia which is evolving and we evolve in it. Yet where does Gaia evolve to? Jonas suggests that evolution is a progressive freedom of action. This certainly applies to individual organisms. The animal feeds on existing life, continuously destroys its mortal supply and has to seek elsewhere for more. The appearance of directed long-range motility thus signifies the emergence of freedom of action.

Freedom of action in the broader sense is a manifestation of Gaia’s optimality. It may serve as an indicator where Gaia is heading to.


1. Hans Jonas  The Phenomenon of Life- Toward a Philosophical Biology
Northwestern University Press Evanston  Ill  2001

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