Jellyfish as a species are actually older than dinosaurs and sharks.
383
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
Sharks, like other fish, have their reproductive organs in their chests.
248
Tidal forces between the Earth and Moon are slowing the Earth down and pushing the Moon further away.
46
Two dogs were among the Titanic survivors.
262
Water is actually naturally blue.
48
There was once an undersea post office in the Bahamas.
241