288 
DARWINISM 
CHAP. 
beak towards the female, and chuckles with delight,” while he 
has never seen the more plain coloured thrush demonstrative 
to the female. The linnet distends his rosy breast, and 
slightly expands his brown wings and tail; while the various 
gay coloured Australian finches adopt such attitudes and 
postures as, in every case, to show oil' their variously coloured 
plumage to the best advantage. 1 
A Theory of Animal Coloration. 
Having rejected Mr. Darwin’s theory of female choice as 
incompetent to account for the brilliant colours and markings 
of the higher animals, the preponderance of these colours and 
markings in the male sex, and their display during periods 
of activity or excitement, I may be asked what explanation 
I have to offer as a preferable substitute. In my Tropical 
Nature I have already indicated such a theory, which I will 
now briefly explain, supporting it by some additional facts 
and arguments, which appear to me to have great weight, and 
for which I am mainly indebted to a most interesting and 
suggestive posthumous work by Mr. Alfred Tylor. 2 
The fundamental or ground colours of animals are, as has 
been shown in preceding chapters, very largely protective, 
and it is not improbable that the primitive colours of all 
animals were so. During the long course of animal develop¬ 
ment other modes of protection than concealment by harmony 
of colour arose, and thenceforth the normal development of 
colour due to the complex chemical and structural changes 
ever going on in the organism, had full play; and the colours 
thus produced were again and again modified by natural selection 
for purposes of warning, recognition, mimicry, or special pro¬ 
tection, as has been already fully explained in the preceding 
chapters. 
Mr. Tylor has, however, called attention to an important 
principle which underlies the various patterns or ornamental 
markings of animals — namely, that diversified coloration 
follows the chief lines of structure, and changes at points, such 
as the joints, where function changes. He says, “ If we 
take highly decorated species — that is, animals marked by 
1 Descent of Man, pp. 401, 402. 
2 Coloration in Animals and Plants, London, 1880. 
