The Origin of Species by Means of Natural Selection: Or, the Preservation of Favoured Races in the Struggle for Life, 6th Edition · Charles Darwin
CHAPTER V. — LAWS OF VARIATION.
Chapter 5 of 28 · 1 min read
Effects of changed conditions—Use and disuse, combined with natural selection; organs of flight and of vision—Acclimatisation—Correlated variation—Compensation and economy of growth—False correlations—Multiple, rudimentary, and lowly organised structures variable—Parts developed in an unusual manner are highly variable; specific characters more variable than generic; secondary sexual characters variable—Species of the same genus vary in an analogous manner—Reversions to long-lost characters—Summary.
