This program describes the detective work and evidence for the generally accepted causes of two of the five mass extinctions, the KT and Permian. Then follows a diatribe on the speculation t... Read allThis program describes the detective work and evidence for the generally accepted causes of two of the five mass extinctions, the KT and Permian. Then follows a diatribe on the speculation that human civilization may cause the sixth mass extinction.This program describes the detective work and evidence for the generally accepted causes of two of the five mass extinctions, the KT and Permian. Then follows a diatribe on the speculation that human civilization may cause the sixth mass extinction.