Image: Darwin Tree 1837

Description: Charles Darwin's 1837 sketch, his first diagram of an evolutionary tree from his First Notebook on Transmutation of Species (1837). Interpretation of handwriting: "I think case must be that one generation should have as many living as now. To do this and to have as many species in same genus (as is) requires extinction . Thus between A + B the immense gap of relation. C + B the finest gradation. B+D rather greater distinction. Thus genera would be formed. Bearing relation" (next page begins) "to ancient types with several extinct forms"
Title: Darwin Tree 1837
Credit: [1]
Author: Charles Darwin
Permission: This work is in the public domain in its country of origin and other countries and areas where the copyright term is the author's life plus 70 years or less. This work is in the public domain in the United States because it was published (or registered with the U.S. Copyright Office) before January 1, 1923. This file has been identified as being free of known restrictions under copyright law, including all related and neighboring rights.
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License: Public domain
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