Kissing releases masses of oxytocin, a "love potion" that helps couples bond and feel more attracted to each other.
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Dolphins have names for one another.
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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.
25
Some British police cars carry a teddy bear to console children after an accident.
46
When dragonflies mate, their tails form a love heart.
22
A zoo in China gave a gay penguin couple the opportunity to raise a chick.
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