Colourful and Deadly – The Cone Shell.

A weekly feature named ‘The Hunter’s High Road.’ Each Tuesday check back to see an animal that represents the apex of predatory evolution. Carnivores come in a range of shapes and sizes, using a variety of tricks to catch their prey. Some are powerful, some are beautiful. All are deadly.

Conus-geographicus

This week I’m covering the Cone Shell, an ocean dwelling snail that has a sting venomous enough to be fatal to humans. With over 800 species they are found in warm and tropical waters, reaching great diversity in the Western Indo Pacific region. The snails lives on coral reefs and sand. When living in sand they bury themselves with only the siphon protruding on the surface.

What makes the Cone Shell an efficient predator is the method of hunting. Each snail is equipped with a poisonous harpoon used to skewer and paralyse prey. The harpoon is a modified tooth that forms inside the mouth in a structure called the radula. The tooth is barbed and hollow, attached to the tip of the radula. When a snail detects prey it extends a flexible tube called a proboscis. The harpoon tooth is fired via a powerful muscle contraction and the prey is paralysed instantly.

All Cone Shells come armed with a battery of harpoons which can be fired from every direction, even backwards. Their diets consist of worms, small fish and molluscs. They aren’t above resorting to cannibalism if necessary. The larger species grow up to 23 cm. Cone Shells are often brightly coloured, making the shells suitable for decoration.

Smaller species of Cone Shells aren’t known to be dangerous, with a sting to humans being the equivalent of a wasp. The larger species can be risky to humans as their harpoon is capable of puncturing skin through gloves and wetsuits. Symptoms of the sting include intense pain, numbness, swelling, vision alteration and breathing problems that prove fatal.

Cone Shell venom has been used in a variety of pharmaceutical advances because of the speed and precision of the various components. Ziconotide, the first pain killer derived from Cone Shell venom was approved in 2004 by the US Food and Drug Administration. Another example is the venom of the magician cone being a 1000 times more powerful than morphine as a non-addictive pain reliever.

Cone Shells are proof that predators come in all forms. Size and power aren’t everything. Even the smallest animal is deadly when perfectly adapted to its environment and comes with a sinister specialisation.

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