Boredom can lead to madness in parrots.

When caged by themselves and neglected for long periods of time, these intelligent, sociable birds can easily become mentally ill. Many inflict wounds upon themselves, develop strange tics, and rip out their own feathers. The birds need constant interaction, affection, and mental stimulation; some bird authorities have determined that some parrot breeds have the mental abilities of a 5-year-old human child. Should a neglected parrot go mad, there is little that can be done to restore it to normalcy. In England, there are "mental institutions" for such unfortunate creatures.

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