. Evolution and animal life; an elementary discussion of facts, processes, laws and theories relating to the life and evolution of animals . ng in the females of variousbird species), or, finally, char-acters connected with specialhabits of one sex differing fromthose of the other (the pollenbaskets and wax plates of the worker female honey bees, the winglessness of certain femaleparasitic insects, the males being nonparasitic and winged, etc.). The special characters may beapparently for the purpose of attract-ing or exciting the other sex, as thebrilliant colors, markings, and otherornamenta
. Evolution and animal life; an elementary discussion of facts, processes, laws and theories relating to the life and evolution of animals . ng in the females of variousbird species), or, finally, char-acters connected with specialhabits of one sex differing fromthose of the other (the pollenbaskets and wax plates of the worker female honey bees, the winglessness of certain femaleparasitic insects, the males being nonparasitic and winged, etc.). The special characters may beapparently for the purpose of attract-ing or exciting the other sex, as thebrilliant colors, markings, and otherornamentation of many male birds,some mammals, and some reptilesand very many fishes, and the criesand songs, special odors, and curiousantics or dancing of the males ofvarious animals (mammals, birds,spiders, insects, etc.). In many ofthese cases the special secondarysexual characters appear only during-A male frog, Pipa ih breeding season; in others they americana, carrying eggs in pits on its back. (After Darwin.) are persistent. FIG. 42.—Fore leg of male water beetle,Dyticus, showing special suckerlikeexpansion of the leg. (After Miall.). 74 EVOLUTION AND ANIMAL LIFE The characters may also be of the type called reciprocal,t hat is, organs which exist in functional condition in one sex, butin the other appear in rudimentary and often nonfunctionalforms, as the reduced horns of female antelopes and goats, theundeveloped stridulating organs of female crickets and katydids,small spurs on the female pheasant, reduced mamma? of malemammals, undeveloped mimicry of male butterflies, etc.
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