environmental
alone
animal
annoyed
ape
bar
bars
behind
brown
cage
caged
captive
captivity
captured
chimpanzee
concept
environment
exhibit
face
fauna
fence
gorilla
hairy
help
herbivore
in
iron
jail
laboratory
locked
lonely
male
mammal
monkey
natural
nature
portrait
primate
prison
sad
sadness
sentence
small
stress
suffer
tropical
urban
wild
wildlife
zoo