Stephen Jay Gould has often written on the nature of nature. Each month, he writes an article for Natural History magazine. Last year, he wrote a special introductory comment on evolution (The Power of This View of Life, Natural History, Vol. 103, No. 6, June 1994, pg. 6-8.) I would like to share some excerpts for you to ponder:
Evolution therefore entered Western consciousness as the most threatening of all new ideas to our most fundamental social assumption and psychological hope for human uniqueness and centrality. Evolution in any guise had to pose a challenge and initiate a crisis.....evolution comes to us, largely via Herbert Spencer, from an English vernacular usage meaning "progress." Darwin did not like the word and preferred "descent with modification." But most evolutionists did equate biological change with progress, and Spencer's favored term stuck....Natural selection is, first of all, a theory about adaptation to changing local environments, not about "improvement" or "progress" in any global sense. Since environments alter in a meandering and unpredictable way through time, natural selection should not lead to any pathway of stately unfolding....Moreover, natural selection, expressed in inappropriate human terms, is a remarkably inefficient, even cruel process. Selection carves adaptations by eliminating masses of the less fit - imposing hecatombs of death as preconditions for limited increments of change....No trend of complexity or progress exists in the usual sense; the history of life features no upward thrust as a central tendency of evolution...In a basic anatomical sense, the history of life since then has been a tale of many variations on a few underlying themes...Mass extinctions punctuate the history of life, imposing regimes of death for reasons unrelated to Darwinian struggles of normal times. If a large extraterrestrial body had not struck the earth 65.3 million years ago, dinosaurs would probably still be dominating mammals, and no conscious being would have the privilege of pondering a world queerer than we can suppose....Darwin's revolution remains incomplete, in Freud's crucial sense, until we face the cosmic insignificance that our own evolution truly implies - thus liberating us to grasp the deeply human meaning of our lives and most curious brainpower...
At this point, turn to the computer module on Natural Selection.
It will help if you have read the two chapters of the Essentials text. Read
these chapters taking notes on only the most primary information. This will
help you understand the computer module where I have identified important
information. Read through this computer program to get an overview of how
natural selection operates. Take notes on those things that are new to you
- especially new terminology. Once you have finished this module, read on
about basic genetics in a separate computer module on genetics. Class discussions
will focus on reinforcing information pertained in these two computer modules.