The Palæontological Evidence for the Transmission of Acquired Characters¹

Abstract

MUCH of the evidence brought forward in France and Germany in support of the transmission of acquired characters, which has been so ably criticized in Weismann's recent essays, is of a very different order from that forming the main position of the so-called Neo-Lamarckians in America. It is true that most American zoologists, somewhat upon Semper's lines, have supported the theory of the direct action of environment, always assuming, however, the question of transmission. But Cope, the able if somewhat extreme advocate of these views, with Hyatt, Ryder, Brooks, Dall, and others, holding that the survival of the fittest is now amply demonstrated, submit that, in our present need of an explanation of the origin of the fittest, the principle of selection is inadequate, and have brought forward and discussed the evidence for the inherited modifications produced by reactions in the organism itself—in other words, the indirect action of environment. The supposed arguments from pathology and mutilations have not been considered at all: these would involve the immediate inheritance of characters impressed upon the organism and not springing from internal reactions, and thus differ both in the element of time and in their essential principle from the above. As the selection principle is allowed all that Darwin claimed for it in his later writings, this school stands for Lamarckism plus—not versus—Darwinism, as Lankester has recently put it. There is naturally a diversity of opinion as to how far each of these principles is operative, not that they conflict.