Systems, a Powerful Part of Evolution

Speaking of ant rafts (my last post), I recently read The Superorganism: The Beauty, Elegance, and Strangeness of Insect Societies, by Bert Holldobler and E. O. Wilson.

         “Superorganism” is a good name for an ant colony or a bee colony or a termite colony.  The individual insects in such colonies are not like you and me.  They don’t strive for individuality.  Instead, they are part of a highly efficient, highly successful system.

         To quote Holldobler and Wilson, “The principal target of natural selection in the social evolution of insects is the colony, while the unit of selection is the gene.”  Ants truly live the principle of “All for one, and one for all.”  Though the worker ants do not themselves reproduce, the expression of genes in each individual responds to colony-wide signals from the queen and from one another; so the individual genes that lead to success are favored.

         Then there is a quite different book, Wetware: A Computer in Every Living Cell, by Dennis Bray.  Much simplified, Bray’s point is that in a unit as small as a cell, the activities of thousands and millions of molecules are like electric circuits, providing information and carrying messages that lead to actions.

         Bray describes the complex, overlapping systems of molecular signals within a cell.  Then he considers the possibility that it is not just genes, but systems that control the expression or non-expression or slight expression of genes that actually evolve.  Some combinations of expression are more successful than others for a particular species.  So not only the genes in question, but the control systems that lead to successful expression patterns, are conserved.

         I find this whole idea of evolving systems just breathtaking.  How about you?