When a male gentoo penguin "falls in love" with a female penguin, he searches the entire beach to find the perfect pebble to present to her.
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The Savannah is the largest domestic cat breed. It resembles a small leopard and behaves like a dog. They can grow up to 40 lbs, have an eight foot vertical jump, and can be trained to walk on a leash and play fetch.
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Kissing releases masses of oxytocin, a "love potion" that helps couples bond and feel more attracted to each other.
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Sergeant Stubby was the only war dog to be promoted to sergeant through combat in WWI. He saved his regiment from surprise mustard gas attacks, found and comforted the wounded, and even once caught a German spy by the seat of his pants, holding him there until American Soldiers found him.
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