From one Darwin to another: Charles Darwin’s annotations to Erasmus Darwin’s ‘The Temple of Nature’

In the history of evolutionary thought, it has often been said that ideas on the transformation of species found in the work of Erasmus Darwin, principally as set forth in his The Temple of Nature (1803), inspired his grandson’s theory of evolution. However, little historical evidence has been produced to back up this claim. Based on a physical examination of Charles Darwin’s own copy of The Temple of Nature, this paper presents the 25 markings Darwin made in the book as evidence of his interest in and familiarity with Erasmus Darwin’s ideas on the change over time across species. This finding contradicts previous statements reporting only two annotations, which suggested he had little to no interest in the book. This paper purposes that Charles Darwin’s annotations indicate his and his grandfather’s shared interest in the competition for reproduction (sexual selection) and point to a more remarkable resemblance between Erasmus Darwin’s The Temple of Nature and Charles Darwin’s The Descent of Man (1871) rather than to Charles Darwin’s theory of evolution by means of natural selection (The Origin of Species), to which Erasmus’s ideas are more often compared.