Scientific Progress Consists In The Development Of

New Gene Pools Are Generated In Every Generation, And Evolution Takes Place Because The Successful Individuals Produced By These Gene Pools Give Rise To The Next Generation.

The Issue, As Correctly Emphasized By Carl Sagan, Is The Probability Of The Evolution Of High Intelligence And An Electronic Civilization On An Inhabited World. Once We Have Life (and Almost Surely It Will Be Very Different From Life On Earth), What Is The Probability Of Its Developing A Lineage With High Intelligence? On Earth, Among Millions Of Lineages Of Organisms And Perhaps 50 Billion Speciation Events, Only One Led To High Intelligence; This Makes Me Believe In Its Utter Improbability.

A New Species Develops If A Population Which Has Become Geographically Isolated From Its Parental Species Acquires During This Period Of Isolation Characters Which Promote Or Guarantee Reproductive Isolation When The External Barriers Break Down.

Evolution ... Is Opportunistic, Hence Unpredictable.

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.