8 FOREWORD 
animals in the wild ; but not being coddled by the normal 
members of the species, they have a poorer chance than 
has the subnormal human of surviving and of transmit- 
ting their peculiarities. 
Fear, ennui, loneliness and nostalgia, by affecting the 
minds of captive animals, react on their physical condi- 
tion. Some animals have the fear of man bred in them. 
The young often show it from time of birth. This is 
especially common in animals that have survived for gen- 
erations in proximity to man. It is one reason for their 
survival. The mother and father may have become tame 
and gentle in capti\dty and yet the young one may be a 
wild thing from birth. Such fear is sometimes uncontrol- 
lable, an apparently slight cause making the animal dash 
itself against the fence of the enclosure. It is not mere 
speculation to discuss the physical effects of the emotions 
on the animal body. It has been shown that fear, anger, 
and grief bring about distinct measurable physical 
changes. Dr. Corson-AVhite has found that the red cor- 
puscles are increased by over two million per cubic 
centimetre in the blood of a cat frightened by a dog bark- 
ing at it. The amount of blood sugar is also increased. 
Such observations are suggestive in a consideration 
of the changes that may occur in a captive animal sub- 
jected to acute and chronic fear. 
The monotony of a captive animal 's life is broken only 
by feeding, the sight and sounds of others in the same 
building or nearby, and by visitors. Many animals show 
their appreciation and pleasure when visitors approach, 
and some of the more intelligent animals, bears and 
monkeys and some birds, *' show off " apparently to keep 
the visitors there. When there is nothing doing, some 
stand swaying their heads, like a weaving horse, or pacing 
the cage, inanely tagging at each turn the side of the cage 
with the head or other part of the body — often so persist- 
ently that a sore is produced. Nearly all animals are 
social and suffer from loneliness when kept by themselves. 
