@dogfacts

During the Renaissance, detailed portraits of the dog as a symbol of fidelity and loyalty appeared in mythological, allegorical, and religious art throughout Europe, including works by Leonardo da Vinci, Diego Velázquez, Jan van Eyck, and Albrecht Durer.

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A dog's nose is the equivalent of a human's fingerprints, as no two dogs have the same nose print.

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A German Shepherd guide dog led her blind companion the entire 2,100 mile Appalachian Trail.

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Dogs were first domesticated by cavemen.

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There are about 400 million dogs in the world.

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Dogs can get jealous when their humans display affection toward someone or something else.

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Chocolate contains a substance known as theobromine (similar to caffeine) which can kill dogs or, at the very least, make them violently ill.

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It costs approximately $10,000 to train a federally certified search and rescue dog.

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The wetness of a dog's nose is essential for determining what direction a smell is coming from.

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Dogs have a third eyelid called a nictitating membrane, which helps to protect their eyes and keep them moist.

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Dogs can be trained to detect cancer and other diseases in humans.

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A dog's sense of smell is about 10,000 times stronger than a human's.

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It is much easier for dogs to learn spoken commands if they are given in conjunction with hand signals or gestures.

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A German Shepherd guide dog led her blind companion the entire 2,100 mile Appalachian Trail.

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National Geographic's Dr. Brady Barr measured a dog's average bite force at 320 pounds of pressure per square inch.

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