xi, c, 4 Copeland: Natural Selection 167 
One of Doctor Willis’s objections to natural selection (p. 321) 
escapes me completely: 
Natural selection, again, to be effective, requires that many forms shall 
modify in the same direction. * * * The most numerous group of the 
Ceylon endemics are these Very Rares, and the numbers decrease steadily 
up to Very Common. They must obviously have begun at one or other end 
of the scale. They could not begin at Very Rare (on the theory of natural 
selection), because the numbers are insufficient. 
I do not believe that natural selection, to be effective, requires 
that many forms shall modify in the same direction. If “modify” 
means “vary,” I am skeptical as to there being any evidence, 
proving that many forms ever do this in the same direction. 
Natural selection, to produce a definite species, requires rather 
that a fit form maintain its advantageous characteristics without 
modification, while the individuals can become numerous and 
spread. A single isolated individual, well adapted to its location, 
may surely become the ancestor of a common species. If the 
theory of natural selection really required that a species could 
not come into existence at “Very Rare,” but must be very common 
at its first appearance, it would be a strange theory indeed. It is 
hardly fair to a theory to impute to it quite that measure of 
absurdity. 
On page 340, Doctor Willis says, “One may conclude that 
the local endemic species have not been developed in any kind 
of advantageous response to local conditions.” More explicitly, 
on page 15 of the Annals of the Royal Botanic Gardens, volume 
IV, he says, “It is at least entirely doubtful if any given species is 
especially adapted for the circumstances in which it is found.” 
This shows how widely men of training and field experience may 
differ in their views. For, aside from the distinctive features of 
possible ephemeral species, 1 do not believe that there is a plant 
in the world that does not exhibit adaptation in the whole of 
its structure, nor which, so far as it is restricted to localities 
by environmental conditions, fails to be specifically adapted to 
the local conditions under which it thrives. My paper on the 
Comparative Ecology of San Ramon Polypodiaceae contains 
hundreds of illustrations of particular adaptions to particular 
local conditions. It is not merely that water plants and land 
plants differ, or that plants restricted to the shade differ from 
those thriving in open sunshine; but that in genus after genus, 
where the genus has species under varying conditions, the 
different species differ from one another in ways that specifically 
adapt them to their distinctive environments. 
