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
In 2011, archaeologists discovered the skeletal remains of a Roman couple who have been holding hands for 1,500 years.
81
A newborn Chinese water deer is so small, it can (almost) be held in the palm of a hand.
13