Darwin from Descent of Man to Emotions Darwin from Descent of Man to Emotions Between 1868 and 1872, the life and work of Charles Darwin from "Descent of Man" to "Emotions" continued with aspects of his intended "Big Book" on evolution through natural selection. He had by then hurriedly published an "abstract" of this work as "On the Origin of Species" in 1859, and following the immediate reaction to Darwin's theory his earlier work included demonstrating the utility of the flowers of Orchids in directing insect pollination to achieve cross fertilisation, and a summing up of thirteen years of experiments in "The Variation of Animals and Plants
The Descent of Man, and Selection in Relation to Sex to the forces of sexual selection. While debates on the subject continues, in January 1871 Darwin started on another book, using left over material on emotional expressions, which became "The Expression of the Emotions in Man and Animals". In recent years controversy also involved the peacock tail, the most famous symbol of the principle of sexual selection. A seven-year Japanese study of free-ranging peafowl came to the conclusion that female peafowl do not select mates merely on the basis of their trains. Mariko Takahashi found no evidence that peahens expressed any preference for peacocks with more elaborate trains, such as