Sea otters hold hands while sleeping so they don’t drift away from each other.
104
Sharks, like other fish, have their reproductive organs in their chests.
248
The North Atlantic gets 2.5 centimetres (1in) wider every year.
119
The Caspian Sea is also classed as the world's largest lake.
52
More than a dozen men have stood on the surface of the moon, but only three have been to Challenger Deep in the Marianas Trench, the deepest known spot in the ocean.
17
NYC's Metropolitan Transit Authority (MTA) dumps old subway cars into the ocean to serve as artificial reef.
8
Two dogs were among the Titanic survivors.
262
It's impossible to sink in the Dead Sea without equipment!
72