The earliest and most primitive known members of every order already have the basic ordinal characters, and in no case is an approximately continuous sequence from one order to another known. In most cases the break is so sharp and the gap so large that the origin of the order is speculative and much disputed.

If a sect does officially insist that its structure of belief demands that evolution be false, then no compromise is possible. An honest and competent biology teacher can only conclude that the sect's beliefs are wrong and that its religion is a false one.

The opposition to teaching evolution is, of course, almost always given a religious reason. That may usually be its real basis, but I think it is often a mask, perhaps unconscious, for underlying anti-intellectualism or antiscientism.

The science of systematics has long been affected by profound philosophical preconceptions, which have been all the more influential for being usually covert, even subconscious.

Certainly paleontologists have found samples of an extremely small fraction, only, of the earth's extinct species, and even for groups that are most readily preserved and found as fossils they can never expect to find more than a fraction.

Man stands alone in the universe, a unique product of a long, unconscious, impersonal, material process with unique understanding and potentialities. These he owes to no one but himself, and it is to himself that he is responsible. He is not the creature of uncontrollable and undeterminable forces, but is his own master. He can and must decide and manage his own destiny.

A rill in a barnyard and the Grand Canyon represent, in the main, stages of valley erosion that began some millions of years apart.