‘ CRITIQUE OF DARWINISM 253 
of Darwinism at the hands of Professor V. L. Kellogg as it appears in 
his book Darwinism To-Day. 
A much briefer and considerably more general defense is that of 
J. L. Tayler, which is as follows: 
GENERAL DEFENSE OF DARWINISM" 
J. L. TAYLER 
To realise how far the theory of selection is capable of explaining 
the facts of organic evolution, it is necessary to bear in mind the 
postulates in which the theory is founded. 
1. It is obvious that natural selection can only act by preserv- 
ing or eliminating the complete organism. Selection must therefore 
be organismal. This Darwin and other selectionists have clearly 
recognised. 
2. As the whole organism must survive, if the favourable variation 
or variations are to be preserved, it follows that certain minor un- 
favourable variations may also be preserved if they happen to exist 
in an individual which survives on account of its major favourable 
variations. And since no individual is completely adapted to its 
environment, it follows that there must be always a variable amount 
of residual unfavourable variability in every organism. 
3. This residual unfavourable variability may be of considerable 
utility under changed conditions. 
4. Complementary specialisation of parts, as Spencer has shown, 
is favourable to successful competition, and as it is the whole organism 
that is selected or eliminated, it follows that any weakness of one 
specialised part, since it would disturb the balance of all, would be 
detrimental. The more complex the organism, the more specialised 
the structures, the more dependent one part will be on the others for 
its existence, hence a complementary specialising tendency will be 
favoured by selection, and therefore all struggles of one part of an 
organism with another will be reduced to a minimum. 
It is clear that there must be some underlying criterion which 
determines whether any given organism shall be selected or not, and 
that criterion must be the net result of its adaptability to its environ- 
ment. One organism may conceivably survive, by its possession of 
a large number of small favourable variations, while another may 
survive in virtue of a single valuable one, but in each case it would be 
* From J. L. Tayler, “The Scope of Natural Selection,” Natural Science, 1899. 
