138 THE MEANING OF EVOLUTION 
ber of rivals, and they are not willingly displaced. 
Accordingly we find that polygamy is usually accom- 
panied by a belligerent disposition on the part of the 
males. In our ordinary barnyard fowl this trait is 
very evident. The rooster not only domineers over 
the hens, not only struts about among them in stately 
fashion and gives vent to his feelings by his sonorous 
voice, he must also drive away from the neighborhood 
any rivals for the affections of his wives. Hence the 
rooster attacks upon sight the neighboring rooster, 
and battles with him to his entire discomfiture and 
sometimes to the death. 
Among the members of the deer family this partic- 
ular phase of the relation between the sexes has pro- 
duced in the males, and only very rarely in the fe- 
males, the magnificent branching horns. These are 
intended not so much as a protection against the 
enemy as for an offensive weapon in the battle for the 
mates. 
Beautiful and stately as are these magnificent horns, 
they last only for a part of the year. We begin to 
understand their meaning. When the wolf is hungri- 
est, toward the close of the bitter winter, the deer is 
without horns. When the time for mating comes, the 
deer within a few weeks grows his horns, which at 
first are covered with a plushlike coating, known as 
velvet. After a while this dries and he rubs his horns 
