When you fall in love, that 'high' feeling is caused by a flood of dopamine that is similar to that of cocaine.
44
A man's beard grows fastest when he anticipates sex.
239
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
The single biggest predictor of love is proximity.
30
Kissing releases masses of oxytocin, a "love potion" that helps couples bond and feel more attracted to each other.
13
Couples' personalities converge over time to make partners more and more similar.
235
Every year around 1 billion Valentine cards are sent. After Christmas it's a single largest seasonal card-sending occasion.
14
In 2011, archaeologists discovered the skeletal remains of a Roman couple who have been holding hands for 1,500 years.
81