alone
animal
ape
bar
bars
behind
cage
caged
captivity
captured
cell
child
chimpanzee
closeup
concept
creature
depression
disaster
environment
environmental
exhibit
face
fence
gorilla
hold
idea
iron
jail
laboratory
locked
lonely
mammal
metal
monkey
natural
nature
portrait
primate
prison
sad
sentence
small
species
stress
suffer
tame
urban
wild
wildlife
zoo