As A Consequence, Geneticists Described Evolution Simply

Wherever We Look At The Living Biota … Discontinuities Are Overwhelmingly Frequent…the Discontinuities Are Even More Striking In The Fossil Record. New Species Usually Appear In The Fossil Record Suddenly, Not Connected With Their Ancestors By A Series Of Intermediates.

Evolution Thus Is Merely Contingent On Certain Processes Articulated By Darwin: Variation And Selection.

The Reduced Variability Of Small Populations Is Not Always Due To Accidental Gene Loss, But Sometimes To The Fact That The Entire Population Was Started By A Single Pair Or By A Single Fertilized Female. These 'founders' Of The Population Carried With Them Only A Very Small Proportion Of The Variability Of The Parent Population. This 'founder' Principle Sometimes Explains Even The Uniformity Of Rather Large Populations, Particularly If They Are Well Isolated And Near The Borders Of The Range Of The Species.

Every Politician, Clergyman, Educator, Or Physician, In Short, Anyone Dealing With Human Individuals, Is Bound To Make Grave Mistakes If He Ignores These Two Great Truths Of Population Zoology: (1) No Two Individuals Are Alike, And (2) Both Environment And Genetic Endowment Make A Contribution To Nearly Every Trait.

Evolution, Thus, Is Merely Contingent On Certain Processes Articulated By Darwin: Variation And Selection. No Longer Is A Fixed Object Transformed, As In Transformational Evolution, But An Entirely New Start Is, So To Speak, Made In Every Generation.