THE COLORATION OF LARGE ANIMALS II 
potamuses, it is fairly safe to assert that among the 
medium-sized and larger mammals the primitive type of 
coloration took the form of either striping or spotting. 
This is demonstrated by the many known instances there 
are of the young being striped or spotted, while the adults 
are more or less uniformly coloured. As_ well-known 
examples of this kind we may cite tapirs, wild swine, many 
kinds of deer, lions, and pumas. In many cases the sub- 
stitution of a uniform dull livery for a spotted or striped 
coat has evidently been in adaptation to an existence in 
open or desert country. Instances of this kind are afforded 
by the lion and the Cape eland, the latter of which has lost 
the stripes characteristic of its more northern representa- 
tive and of the kindred antelopes such as the kudus and 
bushbucks. 
The fact that the young of certain animals haunting 
more or less arid districts, such as the lion, still retain 
their spots, while others, like the eland, differ from their 
relatives inhabiting more wooded country only by the loss 
of their stripes, indicates that in these cases, at any rate, 
the acquisition of a uniformly coloured tawny coat is a 
comparatively recent event, Possibly an explanation of 
this may be afforded by the history of deserts and semi- 
deserts themselves. In contradistinction to the old idea 
that they are ancient upraised sea-beds, it is now well 
known that all desert areas have been formed very slowly 
by the gradual decomposition of the rocks in countries 
where there is no rain to wash away the débris. And it 
seems by no means improbable—owing to the enormous 
lapse of time necessary for their formation, coupled, perhaps, 
with a greater rainfall over most parts of the world in 
earlier epochs—that such tracts never existed until late 
in the earth’s history. 
