'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.
255
The left ear is more responsive to words of love and emotion whispered into it than the right.
44
People are more likely to tilt their heads to the right when kissing instead of the left (65 percent of people go to the right!)
278
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 2011, archaeologists discovered the skeletal remains of a Roman couple who have been holding hands for 1,500 years.
81
In Finland, Valentine's Day is called "Ystävänpäivä" which translates into "Friend's day".
4
When someone looks at a new love, the neural circuits that are usually associated with social judgment are suppressed.
130
Couples' personalities converge over time to make partners more and more similar.
235