Question: What animal is over 30 feet long, has a big head, enormous eyes, a mane like a lion, a long neck, a body like a snake and lots of arms like an octopus?
Answer: Nobody knows.
But sailors have been telling stories about giant creatures of the sea for hundreds of years. The monsters that sailors and fishermen describe are all slightly different but it's often an animal like a giant snake, at least 30 feet long, with an enormous head and neck. It sometimes actually attacks the ship. Some of these sea monsters turned out to be big pieces of seaweed or wood, but other stories are not so easy to explain. So what can these monsters be?
They could be sharks
There is an unusual type of shark that is shaped like an eel. It has a frill around its neck, which could look like a lion's mane. But the biggest one ever caught was only 25 feet long. Another type of shark, the 'basking shark', can grow to about 40 feet in length. In the 1970s a Japanese fishing boat caught an enormous dead 'monster' with a long neck. Scientists tested some small pieces of the animal and discovered that it was a basking shark. When these sharks die, parts of them rot very quickly, which gives them a very strange shape. But this doesn't explain stories about living, moving sea monsters.
They could be just very big snakes
The biggest snake in the world is the anaconda. One was found in the 1940s that measured 35 feet, but there are no photographs to prove it. South American Indians tell stories of even bigger ones. The problem with this theory is that the anaconda is native to South America and can't survive in cold water.
They could be giant squid
This is an interesting theory. Scientists all accept that giant squid really exists but we don't see them very often because they live in deep, cold water. They can be up to 50 feet in length and have the biggest eyes in the animal kingdom – over one foot in diameter. (There are reports of much bigger ones too.) They have a strong mouth like a bird's beak that can cut through steel cables, and five pairs of arms, or tentacles. One pair is longer and thinner than the others and is used to catch food. People have seen giant squid attacking whales for food. In the 1960s some Russian sailors reported watching a fight between a whale and a giant squid. Both animals died; the whale was found dead with the squid's arms wrapped around its neck, and the squid's head was found in the whale's stomach. There are also reports of giant squid attacking ships, maybe thinking that they were whales. So the giant sea snakes wrapped around ships could actually be one or two arms of a giant squid.
They could be giant octopuses
Giant octopuses also exist – there are varieties of octopus with bodies as much as 23 feet around. But there are also stories about an unknown variety that grows much, much bigger. An enormous animal was found dead and rotting on a beach in Florida in the 1890s. Parts of it seemed to be huge arms over 30 feet long. Scientists tested a small part of the body but couldn't agree whether it was a whale or an octopus. Like the giant squid, the giant octopus has a strong mouth like the giant squid but it has only eight arms. It lives at the bottom of the sea and uses its arms to move around over the rocks. This explains why we don't see giant octopuses very often.
Giant octopuses could be ancient sea animals that have survived from the time of the dinosaurs. We know that strange animals lived in the sea during pre-historic times, and many of them were very big indeed. They didn't look like fish and they had to come up to the surface of the water to breathe air. Perhaps, when the dinosaurs died out, these sea creatures survived and have lived in the oceans ever since. Is that possible?
Well, maybe it is. In 1938 a strange fish was caught in the Indian Ocean. Scientists eventually identified it as a coelacanth (pronounced 'seel-a-kanth'), which everyone thought had died out over 70 million years ago. And another type of coelacanth was found in the 1990s in South East Asia.
So, do any of these explanations convince you? Or do you think that deep down at the bottom of the sea, where we have never explored, there are strange creatures that are still completely unknown to science?