EVOLVING THE CAMEL. 



197 



remain in this respect on tlie lowest mammalian level. Their teeth 

 approximate rather to the type which occurs in horses and some 

 other outlying ungulate groups than to the type which occurs in 

 the true ruminants. They have always canines in both jaws ; but 

 these canines are not lengthened out into regular tusks, nor do 

 they serve to any noticeable extent as weapons of warfare. In 

 short, the camels by many points of their structure point back to 

 a time when the ancestors of the ruminants had not diverged at 

 all widely from the ancestors of the horse, the pig, or the hippo- 

 potamus, and they still retain in many particulars the early " gen- 

 eralized," or rather unspecialized, type of the common progenitor 

 of the entire group. 



The llamas and alpacas may be looked upon as the best living 

 representatives of the camel tribe in its primitive state, before it 

 had begun specially to assume its camel-stage. They do not pos-' 

 sess the adaptive peculiarities which fit the camel for its desert 

 existence ; and, on the other hand, they exhibit to the full that awk- 

 ward, ungainly, misshapen type which so often betrays Nature's 

 first rough draught of an evolving order. They are, as it were, 

 the sketchy outline only of the perfected ruminants. Compare for 

 a moment the ugly, shambling, ungraceful alpaca with the red 

 deer, flying over the open Scotch moorland ; the gazelle, springing 

 lightly along the Syrian plains ; the antelope, careering across the 

 South African veldt ; or the chamois, leaping from crag to crag 

 among the frozen Alps, and you will see at once what is meant by 

 the difference between a specialized and a generalized type — the 

 difference between Nature's early attempts in a given line, and her 

 fully evolved and carefully molded final product. 



The antelopes and deer, with their various allies, such as the 

 gnu, the eland, the ibex, the buffalo, the bison, the sheep, the big- 

 horn, and the musk-ox, represent for us the developed ruminant 

 types, produced by fierce competition in the struggle for life in 

 the great continents. Their fleetness of foot, their exquisite horns, 

 their agility, their grace of movement, all depend upon the exist- 

 ence in their native countries of highly evolved beasts of prey, 

 from whose fierce attacks they have had to save themselves by 

 speed and acuteness. To the same cause they owe also the keen- 

 ness of their senses, the slimness of their legs, and to some extent 

 also the elegance and beauty of their entire bodies. The smaller 

 kinds, like the gazelles, are remarkable for their vigilance, their 

 timidity, and their alertness, the hereditary result of ages spent 

 in avoiding the attacks of predatory enemies. Natural selection, 

 in short, has given to the advanced ruminants generally their 

 distinctive rapidity, lightness, and beauty of shape. To sexual 

 selection, on the other hand, they owe their twisted horns or 

 branching antlers, their dappled coats and exquisite markings. 



