6 - The challenge of Lamarckian evolution

Summary

Natural selection…replaces a transcendental explanation with a natural one. To be sure, it does not explain force, and thus leaves the whole subject shrouded in as deep fundamental mysticism as ever. But science does not hope to explain force and power, and will be satisfied to account for natural phenomena by…natural forces acting in accordance with natural laws. Natural selection was a great step in this direction.

H. W. Conn

Evolution has not taken place by the action of ‘Natural Selection’ alone, but…partly, perhaps mainly, through laws which may be most conveniently spoken of as special powers and tendencies existing in each organism; and partly through influences exerted on each such organism by surrounding conditions and agencies organic and inorganic, terrestrial and cosmical, among which the ‘survival of the fittest’ plays a certain but subordinate part.

St George Mivart

The last of Darwin's works directly concerned with organic evolution was the Descent of Man. From the time of its publication until his death in 1882 Darwin occupied himself with long-standing researches which served to illustrate the broader significance of his theory. The first and last fruits of his labour – The Expression of the Emotions in Man and Animals (1872) and The Formation of Vegetable Mould through the Action of Worms, with Observations on Their Habits (1881) – had a psychological interest. Other volumes reported his work on plants: Insectivorous Plants (1875), The Movements and Habits of Climbing Plants (1875), The Effects of Cross and Self Fertilisation in the Vegetable Kingdom (1876), and The Different Forms of Flowers on Plants of the Same Species (1877).