A Critique of the Theory of Evolution
LOUIS CLARK VANUXEM FOUNDATION
THEORY OF EVOLUTION
THOMAS HUNT MORGAN
PROFESSOR OF EXPERIMENTAL ZOOLOGY IN
LECTURES DELIVERED AT PRINCETON UNIVERSITY
FEBRUARY 24, MARCH 1, 8, 15, 1916
Occasionally one hears today the statement that we have come to realize that we know nothing about evolution. This point of view is a healthy reaction to the over-confident belief that we knew everything about evolution. There are even those rash enough to think that in the last few years we have learned more about evolution than we might have hoped to know a few years ago. A critique therefore not only becomes a criticism of the older evidence but an appreciation of the new evidence.
In the first lecture an attempt is made to put a new valuation on the traditional evidence for evolution. In the second lecture the most recent work on heredity is dealt with, for only characters that are inherited can become a part of the evolutionary process. In the third lecture the physical basis of heredity and the composition of the germ plasm stream are examined in the light of new observations; while in the fourth lecture the thesis is developed that chance variation combined with a property of living things to manifold themselves is the key note of modern evolutionary thought.
T. H. Morgan, July, 1916