Wednesday 27 October 2010

Triton

Triton is the name given to the Greek god who is the son of Poseidon and Amphitrite, god and goddess of the sea. Triton is the messenger of the ocean and blows on a conch shell to calm or anger the waves. It's also the name given to a snail. A gigantic marine snail, that is. One particular species, the aptly named giant triton, can see its shell reach more than half a metre in length, some 20 inches. For millennia, people have gathered these shells, drilled a whole in the top and blown it like a trumpet, just like the gods themselves. Although without the godlike control over the sea.

They are a kind of gastropod, a class which includes the other slugs and snails on land and in water. Gastropods are in turn part of the incredibly diverse mollusc phylum, which includes everything from oysters and clams to squid and octopus.

The thing about tritons, something which won't necessarily jump out at you when you think 'slugs and snails', is that they are vicious, merciless predators. Very slow of course, so I guess they have to be pretty merciless to get a chance to eat anything. Who could such slow creature possibly be such a ferocious carnivore with? One answer is obvious, other slugs and snails in the sea. The other, is starfish. 

The triton sniffs out prey using chemosensory organs and moves towards it using its one, big, muscular foot. Gastropod is Greek for "stomach foot" by the way, because they thought it was crawling on its belly. Pff. It's sliding on one big foot of course, ain't that obvious? Anyway, some starfish, by means unknown, can sense the approaching killer snail, and so begins a chase. Yeh, a chase. With the starfish running for its life on thousands of tiny tube feet. As it turns out, one foot slow, thousands of feet slower, and tritons usually catch their mark.

Grabbing hold with the same big foot, it's here that things take a turn for the gory. Molluscs have a tough mouth organ called a radula. It's a bit like a tongue, but it's covered in tiny teeth made of chitin, the same stuff as insect exoskeletons. The triton uses this to cut into the starfish like a buzz-saw, and don't forget that starfish have a weird skeleton made up of calcerous plates held together by everything else that makes up a starfish.


With this done, the triton then uses its saliva to paralyse the starfish so it can tuck in at a leisurely pace, starting with the choicest bits. Some large starfish can get away by losing an arm which will grow back later. Some smaller prey will get eaten whole by the triton, which will spit out the useless defenses, like shells and spikes, later.

Indeed, the triton is one of very few creatures which renders the poisonous spikes of the Crown of Thorns starfish useless. A really big one can eat three of these multi-armed monsters a month. During this same time, each starfish could eat half a square metre of colourful coral, leaving behind grey, algae covered skeletons.

So when millions of tritons are collected, killed and their lovely shells sold on, we don't have godlike control of the sea, just unintended consequences. Less beautiful, lively coral reefs, and more dead, grey ones. The problem is even compounded by the way they breed.

While most gastropods are hermaphrodite, capable of fertilising each other's eggs with each other's sperm, tritons aren't. They have a male female divide and the biggest females lay the most eggs, and are, unfortunately, the most attractive to us humans. Many observers say that big tritons are getting increasingly rare. Even big triton shells are getting rare in the shops, often meaning that smaller one's are simply getting more expensive. Without big hungry tritons roaming the world's warm waters, the crown of thorns can experience population explosions and destroy vast tracts of coral, leaving them eerily vacant for years to come.

There's a simple choice here, and I think the answer is that Life is far more beautiful than its mortal coiled shell.

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