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
One litter of kittens can be produced by more than one father.
57
Kissing releases masses of oxytocin, a "love potion" that helps couples bond and feel more attracted to each other.
13
A newborn Chinese water deer is so small, it can (almost) be held in the palm of a hand.
13