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Show PART !I.-SEXUAL SELECTION. CHAPTER VIII. PRINCIPLES OF SEXUAL SELECTION. Secondary sexual characters - Sexual selection - Manner of action - Excess of males - Polygamy- The male alone generally modified through sexual selection- Eagerness of the maleVariability of the male - Choice exerted by the female- Sexual compared with natural selection- Inheritance, at corresponding periods of life, at corresponding seasons of the year, and as limited by sex- Relations between the several forms of inheritanceCauses why one sex and the young are not modified through sexual selection- Supplement on the proportional numbers of the two sexes throughout the animal kingdom- On the limitation of the numbers of the t\Yo sexes through natural selection. 'VITH animals which have their sexes separated, the males necessarily differ from the females in their organs of reproduction ; and these afford the primary sexual characters. But the sexes often differ in what Hunter has called secondary sexual characters, which are not directly connected with the act of reproduction; for instance, in the male possessing certain organs of sense or locomotion, of which the female is quite destitute, or in having them more highly-developed, in order that he may readily find or reach her; or again, in the male having special organs of prehension so as to hold her securely. These latter organs of infinitely diversified kinds graduate into, and in some cases can hardly be distinguished from, those which are commonly ranked as primary, such as the complex appendages at the apex of the abdomen in male insects. Unless indeed |