66 DOMESTICATED ANIMALS AND PLANTS 
bighorn, and chamois it is the ability to climb where only the 
eagles can follow, and to take flying leaps from crag to crag. 
All species and individuals not possessed of some such natural 
advantage, or with whom the advantage has been rendered worth- 
less, go down early in the struggle. Of course such great natural 
calamities as fire and flood, making wholesale destruction, take 
everything both good and bad, fit as well as unfit. Such events 
come so infrequently and so suddenly that nothing can meet 
their exactions. 
The fate of species, however, is not settled by these sudden 
and calamitous events except in rare cases and for certain 
localities. This fate is settled by the slow and relentless method 
we have described, in which literally thousands of every species 
undertake to supply the cravings of hunger and the needs of 
life to the best of their ability, but go down in the struggle to 
defeat and death, while others carry on the struggle with occa- 
sional success. These alone count in the line of descent. 
The individual and the race. It is, indeed, a savage picture 
that we draw when we attempt to depict nature at work in her 
workshop with living beings for her tools and her materials. 
Everything is relentlessly pursuing its own advantage and spend- 
ing its time in killing and eating or in being eaten in turn as it 
surrenders to the inevitable, —a savage tearing mass of animated 
matter spurred on by instincts not understood and by impulses 
incapable of comprehension, the end of which sooner or later, 
whether successful or unsuccessful in the struggle, is death. 
Looked at in this large way, life at best is but a doleful picture, 
for, as some one has remarked, the life of every animal in the 
wild is a constant terror and its end a tragedy. The pathos of 
It is more than likely that such sweeping changes as the glacial epoch do 
operate to exterminate species at wholesale off the face of the earth. Instances 
are not wanting where species have been stranded by the retreating glacier, 
such as the wild primrose on Mount Washington and on the north side of a 
single ledge in southern Michigan. Many species, too, were swept off as the 
glacier advanced, and were unable to return with its retreat, as in England, 
which has a much simpler flora than has France, just across the Channel. 
