6 _A FIRST CHAPTER 
Among the many changes that have been brought about in the pro- 
cess of evolution, is the matter of Protective Coloration—the resem- 
blance of animals to their surroundings, or, in some instances, to one 
another, by which they are enabled to escape their enemies. Birds, like 
snipe, meadow larks, and quail, and mammals, such as the common gray 
rabbit, so harmonize with the dried grass, leaves, and brush amid which 
they live that it is a difficult matter to see them when at rest. Desert- 
haunting animals, many mice, or on a large scale, some of the African 
antelopes, also blend with their surroundings, and so do the spotted 
young of many shore birds that are brought up on pebbly beaches. On 
the other hand parrots and fruit pigeons are largely green, and thus 
elude observation among the trecs in which they live. Then there are 
some very interesting cases of animals that are doubly protected, 
changing their raiment with the season, harmonizing with leaves and 
grass ia summer and with the snows of winter. Such are the weasels, 
hares, and ptarmigans, and it is a curious fact that those which have 
an extensive north and south range, reaching regions where there is little 
or no snowfall, do not turn white in their southern homes. The white 
color of northern animals may not be entirely for their protection, but 
for their warmth as well, since white does not give out heat so rapidly 
as dark colors. 
A most remarkable mode of protection exists In some marine animals 
which are almost as transparent as glass, the very blood being trans- 
formed to a colorless fluid, so that they can scarcely be distinguished 
from the water in which they dwell. 
Still another method of protective coloration is shown by many 
edible species of animals that bear a strong resemblance in form and color 
to those that are presumably disagreeable on account of peculiarities in 
taste or odor. The term presumably disagreeable is used: for it by no 
means follows that hecause a given flavor is offensive to us, it is equally 
unpleasant to birds and other animals. We know from the few careful 
experiments which have been made, that insects repugnant to us are 
eaten by various animals. Also it is very evident that although the 
vast majority of animals are good to eat they nevertheless are not eaten 
out of existence. 
In some cases colors that at first sight seem conspicuous are really 
protective, as are the stripes of the tiger and the spots of the leopard 
and jaguar, which so suggest patches of light and shade that the animals 
crouch unseen in the jungle. In these particular instances color is | 
not necessary for protection, but.is of service while the animals are stalk- 
ing their prey. 

