38 
SELECTION BY MAN. 
Chap. I. 
standard of usefulness to man, we can understand how 
it is that neither Australia, the Cape of Good Hope, nor 
any other region inhabited by quite uncivilised man, has 
afforded us a single plant worth culture. It is not that 
these countries, so rich in species, do not by a strange 
chance possess the aboriginal stocks of any useful plants, 
but that the native plants have not been improved by 
continued selection up to a standard of perfection com¬ 
parable with that given to the plants in countries an¬ 
ciently civilised. 
In regard to the domestic animals kept by uncivilised 
man, it should not be overlooked that they almost 
always have to struggle for their own food, at least 
during certain seasons. And in two countries very dif¬ 
ferently circumstanced, individuals of the same species, 
having slightly different constitutions or structure, would 
often succeed better in the one country than in the 
other; and thus by a process of “ natural selection,” as 
will hereafter be more fully explained, two sub-breeds 
might be formed. This, perhaps, partly explains what 
has been remarked by some authors, namely, that the 
varieties kept by savages have more of the character of 
species than the varieties kept in civilised countries. 
On the view here given of the all-important part which 
selection by man has played, it becomes at once obvious, 
how it is that our domestic races show adaptation in their 
structure or in their habits to man’s wants or fancies. 
We can, I think, further understand the frequently 
abnormal character of our domestic races, and likewise 
their differences being so great in external characters 
and relatively so slight in internal parts or organs. 
Man can hardly select, or only with much difficulty, any 
deviation of structure excepting such as is externally 
visible; and indeed he rarely cares for what is internal. 
He can never act by selection, excepting on variations 
