'X' became symbolic for a kiss because in the middle ages when alot of people were illiterate and they used to sign documents with an X and then kiss it for sincerity.
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Couples' personalities converge over time to make partners more and more similar.
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You burn 26 calories in a one minute kiss.
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If you mouth the word "colorful" to someone, it looks like you are saying "I love you".
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When someone looks at a new love, the neural circuits that are usually associated with social judgment are suppressed.
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When dragonflies mate, their tails form a love heart.
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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
In 2012, a Chinese man named Xiao Fan had a dress made out of 9,999 red roses for his girlfriend and then proposed - 9 in China means forever
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