Title page of Zoonomia" (1796), authored by Erasmus Darwin (1731-1802), grandfather of Charles Darwin. Zoonomia, or The Laws of Organic Life, was his best book in which he briefly proposed a theory of evolution in response to environmental pressures for the first time, a concept later taken up by his grandson. However, this lengthy poetic precursor to the theory of evolution has the basic error of using Lamarck's ideas that acquired characteristics are inherited. It stands in contrast to his grandson's theory of Natural Selection in which the fittest survive. Erasmus Darwin was a physician and founder of the Lunar Society."