Sea Monsters

GIANT squid, albino killer whales, sea serpents and Loch Ness-like creatures have occupied Earth’s oceans, rivers and lakes for the past 600 million years.
And while most ‘monsters’ on land have been found, much of the deep ocean remains unexplored.
Most accounts of sea monsters were no more than exaggerated explanations, the imaginations of ship crews faced with the unknown. Old wives tales.
But many were real, misinterpreted until modern science could explain their existence.
The emergence in the early 1800s of palaeontology (the study of fossils) confirmed the ancient seas were filled with monstrous creatures.
After the Cambrian explosion of life forms in the oceans about 570 million years ago, most major groups of marine animals emerged such as clams, snails and fish. And so did marine monsters such as extinct eurypterids or sea scorpions which lived 450myo in North America and Europe, and what is now Kalbarri. The first versions were just tens of centimetres in length.
By 420myo, the scary arthropods (invertebrates with exoskeletons, crabs, prawns and barnacles) grew up to 2m in length and could live both on land and in the sea.
About 360myo, placoderms or armour-plated fish, appeared, growing up to 6m-8m long, having lived and died in the world-famous Gogo fossil fish site in the Kimberley.