Dolphins have names for one another.
18
There's a young hippo and a 130+ year old tortoise in a Kenyan wildlife preserve who are best friends and they even sleep and play together.
40
Sandy, an African Penguin, has been in 'love' with her keeper at the Nuremburg zoo since 1996.
34
Kissing releases masses of oxytocin, a "love potion" that helps couples bond and feel more attracted to each other.
13