DARWIN, AUTOGRAPH MS LEAF FROM THE EXPRESSION OF THE EMOTIONS, SIX-LINE FRAGMENT

proposing that when a sensation or emotion has led "during a long series of generations to any voluntary action, then that the same or any analogous or associated sensations &c, although very weak, will almost inevitably give some tendency to the performance of similar movements",  unnumbered fragment, torn at top from a larger leaf, 44 words on 6 lines, with unrelated mathematical calculations in black ink and pencil by George Darwin on the verso, blue wove paper, 1 page, oblong slip (c.102 x 202mm), torn at the head and cut at the foot, 1872, paper discoloured in spots

Charles Darwin; his daughter Henrietta ("Etty") Litchfield (1843-1927); her niece Margaret Keynes, née Darwin (1890-1974); thence by descent

Condition is described in the main body of the catalogue, where appropriate.
"In response to your inquiry, we are pleased to provide you with a general report of the condition of the property described above. Since we are not professional conservators or restorers, we urge you to consult with a restorer or conservator of your choice who will be better able to provide a detailed, professional report. Prospective buyers should inspect each lot to satisfy themselves as to condition and must understand that any statement made by Sotheby's is merely a subjective, qualified opinion. Prospective buyers should also refer to any Important Notices regarding this sale, which are printed in the Sale Catalogue.
NOTWITHSTANDING THIS REPORT OR ANY DISCUSSIONS CONCERNING A LOT, ALL LOTS ARE OFFERED AND SOLD AS IS" IN ACCORDANCE WITH THE CONDITIONS OF BUSINESS PRINTED IN THE SALE CATALOGUE."

THE MANUSCRIPT OF A KEY SECTION IN DARWIN'S FINAL EVOLUTIONARY WORK, IN WHICH HE WRITES DIRECTLY ABOUT EVOLUTIONARY PROCESSES. This section of text is found in revised form on p.48 of the first edition of The Expression of the Emotions in Man and Animals. It comes at the conclusion of the chapter at the end of Darwin's discussion of what he terms "Associated habitual movements in the lower animals". These are habitual actions that have long-since lost any practical function, such as a domestic dog turning round before settling to sleep as if to scoop out a hollow, or a tame Shelduck patting the ground with its feet when asking for food, as its wild cousin would do over a worm-cast. Darwin's argument here is noteworthy as he suggests that learned behaviours can become heritable through repetition. Darwin had ignored this Lamarckian theory of evolution in the Origin, and it has since been proved to be baseless, but it was part of his argument in several of his later works.