
Source: 1860s, Evidence as to Man's Place in Nature (1863), Ch.2, p. 126
excerpt follows
Gardeners' Chronicle
Source: 1860s, Evidence as to Man's Place in Nature (1863), Ch.2, p. 126
Source: The Geological Evidences of the Antiquity of Man (1863), Ch.21, p. 410
https://twitter.com/richarddawkins/status/566866395540246528 (15 February 2015)
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Source: What On Earth Is About To Happen… For Heaven’s Sake? (2013), pp. 34-35
Darwin's first published expression of the concept of natural selection.
"On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection" Journal of the Proceedings of the Linnean Society of London: Zoology (read 1 July 1853; published 20 August 1858) volume 3, pages 45-62, at page 51 http://darwin-online.org.uk/content/frameset?pageseq=7&itemID=F350&viewtype=image
Other letters, notebooks, journal articles, recollected statements