When Charles Darwin published On the Origin of Species by Means of Natural Selection in 1859, it was a beginning, not an end, to his theory of evolution by natural selection. No scientific theory is accepted without question, especially not one as controversial as Darwin's. In the late 1800s and early 1900s, a great many scientists accepted that life had evolved, but explicitly rejected Darwin's explanation of evolution by variation and natural selection. These skeptics were not creationists who opposed Darwin for religious reasons. They were scientists who were as yet unconvinced by Darwin's arguments and evidence. Some of them were just plain wrong, and were eventually proved wrong by new discoveries. Others were right, but failed to see that their "alternative" theories were actually no more than variants on Darwin's own ideas.
BERGSON'S CREATIVE EVOLUTION
Bergson, Henri
c.1911, Henry Holt
An English translation of Bergson's book defending his version of evolutionary theory. Bergson saw evolution as a creative, discontinuous process guided by a progressive force. Today his position would probably be called a variant of theistic evolution.
THE MATERIAL BASIS OF EVOLUTION
Goldschmidt, Richard
c.1940, Yale Univ. Press
Richard Goldschmidt's masterwork on his view of evolutionary theory. On the whole, a fairly good look at evolutionary theory circa 1940. Like any other circa-1940 biology book, some of it has survived the test of time and new findings, and much of it hasn't. Goldschmidt was a top-flight geneticist for his time, with a remarkable level of intuition concerning the aspects of genetics that weren't yet known. Unfortunately, the book is often remembered mainly for Goldschmidt's flawed "hopeful monster" hypothesis, though this takes up only a couple of pages.
MODERN BIOLOGY AND THE THEORY OF EVOLUTION
Wasmann, Erich
c.1910, Paul, Trench, Turner, & C
Translated English version of Wasmann's textbook on biology and evolution as it was being taught in Germany at the turn of the century.
TEXTBOOK OF EVOLUTION AND GENETICS
Lindsey, Arthur
c.1929, MacMillan
Another textbook on evolutionary theory as of the early 20th century. This one is from a genetic standpoint, reflecting what biologists had learned in thirty years of experimenting with genes.
