The Cambrian sea was a very strange and alien place ... Watch First Animals on The Nature of Things.

In short, it's an amazing place. Here's a list of some of the most mind-boggling things we've already found in the depths of the sea.

In 1863, a Russian paleontologist and mining engineer made his way through the Eocene strata of the Caucasus to the shores of the Caspian Sea ... of ghost islands and strange fireballs over ...