Evolution Is One Of The Two Or

Life Is A Copiously Branching Bush, Continually Pruned By The Grim Reaper Of Extinction, Not A Ladder Of Predictable Progress.

Mass Extinctions May Not Threaten Distant Futures, But They Are Decidedly Unpleasant For Species Caught Up In The Throes Of Their Power.

Each Of The Major Sciences Has Contributed An Essential Ingredient In Our Long Retreat From An Initial Belief In Our Own Cosmic Importance. Astronomy Defined Our Home As A Small Planet Tucked Away In One Corner Of An Average Galaxy Among Millions; Biology Took Away Our Status As Paragons Created In The Image Of God; Geology Gave Us The Immensity Of Time And Taught Us How Little Of It Our Own Species Has Occupied.

Contingency Is Rich And Fascinating; It Embodies An Exquisite Tension Between The Power Of Individuals To Modify History And The Intelligible Limits Set By Laws Of Nature. The Details Of Individual And Species's Lives Are Not Mere Frills, Without Power To Shape The Large-scale Course Of Events, But Particulars That Can Alter Entire Futures, Profoundly And Forever.

The Absence Of Fossil Evidence For Intermediary Stages Between Major Transitions In Organic Design, Indeed Our Inability, Even In Our Imagination, To Construct Functional Intermediates In Many Cases, Has Been A Persistent And Nagging Problem For Gradualist Accounts Of Evolution.