Excerpt from Sexual Dimorphism in the Animal Kingdom: A Theory of the Evolution of Secondary Sexual It must be admitted that my discussion of Sexual Dimorphism in this work is incomplete, and this in two senses. In the first place, evidence of the kind I have endeavoured to collect is in many cases wanting, and has yet to be obtained in the future. The absence of such information is partly due to the difficulty of obtaining it, to the want of opportunities, and partly to the neglect of opportunities and to the absence of any special efforts to obtain it. It is not my intention by such an assertion to throw the blame upon collectors and field naturalists. Their methods of work are naturally adapted to the ends they have in view, and so long as the minute study of habits and conditions of life is generally regarded as of little importance, so long will the collection of specimens and the discovery of species be considered the chief objects of a zoological expedition. It is strange that even from the point of view of selection more attention has not been devoted since Darwin's time to the study of the particular functions or utilities of special characters. When we desire to know fully the irritations and stimulations produced on living tissues by the special habits of the animal, and how its special organs or characters are affected when they come into action, it is clear that the detailed study of the habits of the living animal becomes still more important. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.