Koko the gorilla responds to a sad moment in her favorite film.
The parrot with the moving last words.
The fact that cows have best friends and get stressed when they are separated.
The two guide dogs who led their owners down 70 floors in the World Trade Center before the towers collapsed on September 11.
The Jack Russell Terrier who gave his life to rescue five children from wild dogs.
The beluga whale who saved a free diver who had cramped up 20 feet below the surface.
The cat who can sense when someone is about to die.
The Staffordshire bull terrier who protected her owner from a machete gang.
The gorilla who remembered his old friend.
The recent discovery that fish use tools to perform tasks.
The German Shepherd who has become a seeing eye dog for a blind spaniel.
The abused circus elephants who were reunited at an elephant sanctuary after 25 years apart.
The amazing story of Christian the lion.
The chimps who grieved for their dead friend.
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