The Basenji dog is the only dog that is not able to bark.
4
A cat rubs against people not only to be affectionate but also to mark out its territory with scent glands around its face. The tail area and paws also carry the cat's scent.
293
Cats are one of the only animals to domesticate themselves and approach humans on their own terms.
20
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 reindeer is the only mammal that can see UV light.
17
Alligators can live up to 100 years.
337
Two dogs were among the Titanic survivors.
262