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
Raj from the Big Bang Theory is married to Miss India.
11
Kissing releases masses of oxytocin, a "love potion" that helps couples bond and feel more attracted to each other.
13
In 2011, archaeologists discovered the skeletal remains of a Roman couple who have been holding hands for 1,500 years.
81