In 565 AD, a monkMonks are groups of religious men who live together and withdraw from the rest of the world. named Saint Columba, travelling through Scotland, came across a group of locals burying a man by the River Ness.¹ The man, they explained, had been swimming in the river when he was attacked by a giant beast.

Columba ended up driving off the creature, but it would not stay below the surface for long. Supposed sightings of the Loch Ness Monster would continue for centuries, and although many turned out to be hoaxesA plan to deceive or trick people., our thirst to find the beast has not abated.

This month, the Loch NessA long and narrow lake in Scotland. It is famous for the Loch Ness Monster, a huge creature that some believe lives in the lake. Centre will hold the biggest hunt for the monster in more than 50 years, calling volunteers from around the world.

The monster has never been proved to exist. But believers point out Loch Ness is the biggest body of water in the UK, 36km long and more than 130m deep.² There is no way of knowing what might be in there.

And today we have the advantage of modern technology. Airborne drones will use thermal imaging to scan the water, and a hydrophoneA microphone which records sounds underwater. will pick up sounds across the lake.

Whether or not Nessie really is out there, it is clear she still has a pull on our imaginations. So why are we so obsessed with monsters?

The word "monster" probably derives from the Latin word "monere", meaning "to warn". So the appearance of certain monsters was historically considered a portentA sign that something is about to happen, especially a bad thing. .

That meant monsters could be used to hold those in power to a good standard of behaviour. For example, in Chinese mythology, an animal called the qilinA hooved creature from Chinese mythology. was thought to appear only if the ruling emperor was truly benevolentWell-meaning and kind..

We have also used monsters to make sense of the world. In the ancient world, the water between Sicily and Italy was very dangerous, and many ships were wrecked there.

The Greeks invented two monsters, Scylla and Charibdis, to explain these hazards. Scylla was a huge beast with many heads that would pick sailors off from the decks of ships, and Charibdis created perilousDangerous. whirlpools by sucking in and spewing out huge quantities of water.

Monsters can also be metaphors for channelling our anxieties. For example, when European sailors first encountered the dodoFirst documented in 1599 on the island of Mauritius in the Indian Ocean. It was a relative of the pigeon, but with no natural predators, they evolved into giants and lost the ability to fly., they spread wild tales about the bird.

The dodo was portrayed as a gluttonousVery greedy. In Christianity, it has traditionally been considered a sin. monster that ate everything it found. It was said to be large enough that a single one could feed 25 men.

Historians now think these stories about the dodo served as a way of expressing people's concerns about imperialismThe practice of growing a country's power through colonisation or force. . Just like the dodo, they feared, European powers were consuming everything that stood in their way.

And monsters can help us think about what it means to be human. In Mary ShelleyShe wrote Frankenstein as part of a contest to write a ghost story. Lord Byron and her husband Percy Bysshe Shelley competed against her.'s Frankenstein, the monster created by the title character becomes a cultivatedRefined and educated. and sensitive person. However, because of his terrifying appearance, others will not accept him.

The monster, increasingly alienatedFeeling isolated or no longer supported. and embittered, finally embraces his monstrous side by murdering his creator's fiancee. The story shows how prejudiceAn idea about something, especially a group of people, that is not based on reality. can become a self-fulfilling prophecySomething that happens because enough people are persuaded that it will.: if people are treated like monsters, they become them.

Yes: Monsters point out problems and help us vent the worries about our lives. They tell us when times are good and when they are not so good, and they make life more exciting.

No: Monsters might have done all of this once, but now we have more rational ways of doing them. Hunting for monsters is just a way for bored rich people to waste money.

Or... Monsters probably do keep us sane, but for the wrong reasons. We dream of monsters because our actual lives seem too humdrum and uneventful. We hunt for them because we can no longer find joy in what actually exists.