Kissing releases masses of oxytocin, a "love potion" that helps couples bond and feel more attracted to each other.
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When cats are happy, they may squeeze their eyes shut.
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Meysi is one of the world's smallest dogs, measuring in at just 7cm tall, 12cm long, and weighing a meagre 250 grams (only slightly heavier than a hamster!)
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A newborn Chinese water deer is so small, it can (almost) be held in the palm of a hand.
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