736 MAMMALIA. 



between carnivores and herbivores, between birds of prey 

 and small mammals ; but combination for mutual defence 

 often mitigates the intensity of the conflict. Teeth and 

 claws, hoofs and horns, are the chief weapons, while the 

 scales of pangolins, the bony shields of armadillos, the spines 

 of hedgehogs and porcupines, and the thick hide of the 

 rhinoceros, may be regarded as protective armature. In 

 keeping their foothold some Mammals are helped by the 

 harmony between their colouring and that of their surround- 

 ings ; thus the white Arctic fox and hare are inconspicuous 

 on the snow, the striped tiger is hidden in the jungle, and 

 many tawny animals harmonise with the sandy background 

 of the desert. 



The majority of Mammals are gregarious; witness the 

 herds of herbivores, the cities of the prairie-dogs, the packs 

 of wolves, the schools of porpoises, the bands of monkeys. 

 Combinations for attack and for defence are common ; 

 sentinels are posted and social conventions are respected ; 

 such migrations as those of the lemming and reindeer are 

 characteristically social. In the beaver village and among 

 monkeys there is combination in work, and their communal 

 life seems prophetic of that sociality which is distinctively 

 human. 



Among Birds, mates are won by beauty of song and 

 plumage ; Mammals not less characteristically woo by force. 

 Rival males fight with one another, and are usually larger 

 and stronger than their mates. The antlers of male deer, 

 the tusk of the male narwhal, the large canine teeth of boars, 

 illustrate secondary sexual characters useful as weapons. 

 But manes and beards, bright colours and odoriferous 

 glands, are often more developed in the males than in the 

 females, and may be of advantage in the rough mammalian 

 courtship. At the breeding season a remarkable organic 

 reaction often affects the animal : the timid hare becomes a 

 fierce combatant, and love is often stronger than hunger. 

 The courtship of Mammals is usually like a storm violent 

 but passing; for, after pairing, the males return to their 

 ordinary life and the females become maternal. Some 

 monkeys are faithfully monogamous ; and exceptional pairs, 

 such as beavers and some antelopes, remain constant year 

 after year ; but this is not the way of the majority. 



