XIT 
WHY DO ANIMALS BECOME, EXTINCT? 
“ And Sultan after Sultan nith his Pomp 
Abode his destined Hour and went his way.” 
Ir is often asked “‘ why do animals become ex- — 
tinct ?” but the question is one to which it is ; 
impossible to give a comprehensive and satis-— 
factory reply; this chapter does not pretend — 
to do so, merely to present a few aspects of i 
this complicated, many-sided problem. iq 
In very many cases it may be said that act- — 
ual extermination has not taken place, but — 
that in the course of evolution one species has } 
passed into another; species may have been — 
lost, but the race, or phylum endures, just as_ 
in the growth of a tree, the twigs and branches” 
of the sapling disappear, while the tree, as a 
whole, grows onward and upward. ‘This is 
what we see in the horse, which is the living 
representative of an unbroken line reaching ~ 
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