It remains true, as every paleontologist knows, that most new species, genera, and families, and that nearly all categories above the level of families, appear in the record suddenly and are not led up to by known, gradual completely continuous transitional sequences.

Human judgment is notoriously fallible and perhaps seldom more so than in facile decisions that a character has no adaptive significance because we do not know the use of it.

I have a debt, a loyalty to the museum; the best place for me to do what I wanted to do.

To put it crudely but graphically, the monkey who did not have a realistic perception of the tree branch he jumped for was soon a dead monkey-and therefore did not become one of our ancestors.

The meaning that we are seeking in evolution is its meaning to us, to man. The ethics of evolution must be human ethics. It is one of the many unique qualities of man, the new sort of animal, that he is the only ethical animal. The ethical need and its fulfillment are also products of evolution, but they have been produced in man alone.

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.

Species evolve exactly as if they were adapting as best they could to a changing world, and not at all as if they were moving toward a set goal.