Corals

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Corals

Paradise – Lost?

At last we came among the Coral Islands of the Pacific, and I shall never forget the delight with which I gazed, when we chanced to pass one, at the pure, white, dazzling shores, and the verdant palm-trees, which looked bright and beautiful in the sunshine. And often did we three long to be landed on one, imagining that we should certainly find perfect happiness there!

R.M. Ballantyne’s children’s classic The Coral Island perfectly captures the magical quality of coral reefs – natural phenomena evocatively described by American oceanographer Sylvia Earle as ‘a jewelled belt around the middle of the planet’. For those of us who happen to live on a wet, windy and decidedly untropical archipelago off the north-west coast of Europe, coral reefs really do evoke an image of paradise, even though slow-growing corals can and do occur in cooler waters off Britain and north-west Europe.

Few natural phenomena are quite as beautiful, or extraordinary, as a coral reef. Even the name evokes bright blue seas and warm tropical breezes, and remote atolls in vast oceans. And then diving beneath the surface of the sea, you enter a new and silent world, shimmering with shards of sunlight.

It’s like floating over a forest canopy, with branching trees and open clearings; but here, instead of birds, tight shoals of fish swim through the foliage, flashing alternately light and dark as they twist and turn to evade predators. Ken Johnson, Coral Researcher at the Natural History Museum, is still mesmerised every time he swims over one: ‘Coral reefs make me feel very happy: they’re beautiful places, you’re underwater, you’re flying over the reefs – complex, three-dimensional structures with all this diversity of life beneath you.’

Many corals look like trees, their branches reaching towards the sky through a layer of clear blue water. But they are double-edged beauties, for the very nature of corals is ambiguous. They look like plants, but are actually animals. They appear to be individuals, but live in colonies, made up of thousands of individual creatures that can only function as part of a greater whole. Those colourful fish patrolling round the reef may be beautiful, but many are also poisonous, while sharks lurk in the shadows, waiting for their chance to grab a passing meal.

Once there were coral reefs throughout the warmer parts of the Mediterranean. Coral (especially red) was highly sought after. A Greek myth explained how Perseus had used the severed head of Medusa (the Gorgon with snakes for hair, whose gaze turned people to stone) to slay a sea monster. An unexpected side effect was that her head turned the surrounding plants and seaweed into coral. The Roman poet Ovid took up the story in his Metamorphoses:

The fresh plants, still living inside, and absorbent, respond to the influence of the Gorgon’s head, and harden at its touch, acquiring a new rigidity in branches and fronds. And the ocean nymphs try out this wonder on more plants, and are delighted that the same thing happens at its touch, and repeat it by scattering the seeds from the plants through the waves. Even now corals have the same nature, hardening at a touch of air, and what was alive, under the water, above water is turned to stone.

The official name for coral still echoes this today: ‘Gorgeia’, meaning ‘of the Gorgon’. Over the centuries coral reefs have inspired authors and artists, naturalists and scientists, poets and filmmakers – everyone from Charles Darwin to David Attenborough – and they have been celebrated in works ranging from Robinson Crusoe and The Coral Island to Finding Nemo. So what exactly are corals? And what does our obsession about them tell us about our concept of paradise – and its opposite – a heaven or hell here on earth?

Corals are part of the largest group of animals on the planet: invertebrates. They belong in the group Cnidaria, which comprises more than 10,000 marine or freshwater creatures, characterised by their jelly-like structure; within this they are in the class Anthozoa (deriving from the Greek meaning ‘flower animals’), which includes sea anemones as well as corals.

The vast majority of corals consist of colonies of many genetically identical polyps, each only a few millimetres in diameter and several centimetres long, but collectively making up some of the largest superorganisms on the planet. Each of these tiny creatures consists of a set of tentacles around a single opening (used both for feeding and excretion), with a hard exoskeleton beneath. Over aeons of time, these hard structures have combined to form what appears to be a single assemblage, creating a coral reef.

Given their static lifestyle, corals must feed on whatever comes close enough: some stinging small fish and plankton with their tentacles. However, most corals get their energy from microscopically tiny, single-celled organisms known as dinoflagellates, which actually live inside the tissues of each individual polyp. To survive, most must live near the surface in shallow seas, usually within 60 metres of the surface, so that they are able to take advantage of sunlight.

Corals may be individual creatures, but they also function at two much larger scales: as treelike colonies, and as entire coral reefs. These can be vast: Australia’s Great Barrier Reef – the largest in the world – comprises almost 3,000 separate sections, and stretches for more than 2,300 kilometres over more than one-third of a million square kilometres – an area almost as large as Germany. The Great Barrier Reef could arguably be considered the world’s biggest living entity, and can even be seen from outer space.

Coral reefs are the most diverse ecosystems in the sea, with more than 25 per cent of all oceanic species living there. They are full of colour and movement, not just because of the corals but also from all the other creatures that make their home there. Yet as Erica Hendy, lecturer in the School of Biological Sciences at Bristol University, points out, the reefs themselves are mostly dead: ‘Coral reefs are made up of skeletons of corals and calcareous algae – organisms that are forming limestone – that are now dead and have been washed ashore to form islands.’

And as she goes on to explain, this means that we may not quite realise what we are looking at when we gaze at a coral reef:

What we are actually looking at is a veneer: the living part might be just a few millimetres, whereas the skeleton can be metres and metres thick. It’s just the very thin layer of tissue on the top that’s living – the rest is the skeleton, laid down incredibly gradually at a rate of just a few millimetres a year, and over time taking over more and more real estate on the reef.

Many human analogies have been used to describe a coral reef: they have frequently been described as underwater cathedrals and gardens, for example. But Ken Johnson sees them more as a kind of farm: ‘Reef-building corals are special because they are an animal, but inside their bodies are small single-celled algae. So corals are farmers, growing their crops inside their bodies.’

The algae are plants, so they use sunlight to photosynthesise, creating food for the coral. In return the coral makes waste products that fertilise the algae. Much of the colour we admire when we look at reefs comes not from the corals but actually from the algae within. But what appears to be a city of colour and light is, in reality, a ferocious, competitive warzone, where it’s every polyp for itself, as Erica Hendy notes:

A reef is also a wall of mouths, with coral tentacles ready to capture any small creature that lands on them. Corals can also release mucus, like a kind of fishing-net, enabling them to capture even smaller particles such as bacteria to feed on. But what’s really striking is there is a constant warfare going on, as they try to take over their neighbours by extruding their stomachs and digesting them alive. So when we look at this beautiful reef, what we’re actually looking at is a battlefield.

And the warzone extends beyond the edge of the reef as corals themselves are also fighting against a variety of enemies: UV radiation produced by the tropical sun, a range of marine predators, and longer-term issues such as pollution and global climate change. The Victorians were particularly fascinated by coral. James Gates Percival tried to capture their beauty in his poem ‘The Coral Grove’:

Deep in the wave is a coral grove,

Where the purple mullet, and gold-fish rove,

Where the sea-flower spreads its leaves of blue,

That never are wet with falling dew,

But in bright and changeful beauty shine,

Far down in the green and glassy brine …

The industrious nature of corals appealed to a society obsessed with progress. They marvelled especially at the way so many organisms came together to build a coherent, functioning ecosystem; one on which they could perhaps model their own rapidly growing empire. Ralph Pite is Professor of English Literature at the University of Bristol: ‘The way in which coral reefs grew could be seen as an emblem of a perfect, harmonious society, in which every tiny polyp contributed to the greater good, and the reef gradually developed from the toil of each individual polyp; just as the British Empire developed out of the toil of individual workers.’

This connection was often made explicit, as in this 1827 poem by James Montgomery, ‘Pelican Island’:

Millions and millions thus, from age to age,

With simplest skill, and toil unweariable,

No moment and no movement unimproved,

Laid line on line, on terrace terrace spread,

To swell the heightening, brightening, gradual mound,

By marvellous structure climbing towards the day …

Each wrought alone, yet all together wrought,

Unconscious, not unworthy, instruments

By which a hand invisible was rearing

A new creation, in the secret deep.

And once religion got involved, the comparison of the nature of coral reefs with our human life went still further – the reef was viewed as a physical and material analogy for our own ability to escape from sin. This was because at low tide, when the sea has retreated, the reef looks just like any other rocky place; but as soon as high tide covers the coral again with water, life immediately returns. As Ralph Pite describes: ‘All the coral creatures start to feed, and the flowers grow; and this sense that beneath what appeared to be dead were living creatures was taken as an allegory for the presence within us of a living soul; that even in people “locked within sin”, as Montgomery would have called it, there was the potential for life.’

But it was undeniable that coral reefs had a darker side too. Their jagged, sharp rocks lurking unseen under the water were notorious for tearing wooden hulls to shreds. Coral reefs were the scene of many shipwrecks and responsible for the deaths of thousands of sailors, who drowned amid the warm seas. The familiar image of coral islands as an earthly paradise competed all the time with a sense of their menacing danger.

Charles Darwin first encountered corals when on the Beagle, one of whose tasks was to map coral reefs, because they presented such a threat to shipping. He’d been intrigued by them long before he saw one for himself.

When the Beagle set out in 1831, the formation of coral atolls was a scientific puzzle. In 1824 and 1825 French naturalists Quoy and Gaimard had observed that the coral organisms lived at relatively shallow depths, but the islands appeared in deep oceans. Darwin set out to test their theory that the atolls formed on the top of dormant volcanoes. He couldn’t actually see the reefs underwater, but he still managed to work out how they formed, hopping from top to top with the aid of a ‘leaping stick’.

Such formations surely rank high amongst the wonderful objects of this world. It is not a wonder which at first strikes the eye of the body, but rather after reflection, the eye of reason. We feel surprised when travellers relate accounts of the vast piles & extent of some ancient ruins; but how insignificant are the greatest of these, when compared to the matter here accumulated by various small animals. Throughout the whole group of Islands, every single atom, even from the most minute particle to large fragments of rocks, bear the stamp of once having been subjected to the power of organic arrangement. [Charles Darwin, Diary from the Voyage of the Beagle, 12 April 1836]

Darwin became so fascinated with them that they formed the subject of his first book, The Structure and Distribution of Coral Reefs, published six years after the voyage, in 1842. He proposed a new – at the time, revolutionary – theory for their origin, suggesting that the different types of reefs and atolls were shaped by the movements of the earth’s crust, way beneath the oceans’ surface. Darwin went on to win the Royal Society’s coveted Royal Medal for his work, and more than 180 years after he first conceived his speculative theory – before he had even seen a coral reef for himself – he has now been proven right.

In 1857 the Scottish children’s author R.M. Ballantyne wrote The Coral Island: A Tale of the Pacific Ocean. His heroes are three boys, who like Robinson Crusoe are marooned on a desert island – in this case a coral reef – after a shipwreck. Brave and resourceful, they thoroughly enjoy their experience. As one of the characters, Peterkin, says, ‘There was indeed no note of discord whatever in that symphony we played together on that sweet coral island.’ The book was an instant success, appealing to boys eager for colour and adventure amid the regulations and dullness of Victorian schools.

The Coral Island is far more than a Boys’ Own adventure story. It deliberately touches on a wide range of themes that, although they might have passed over the heads of many of its readers, would have appealed to their parents and teachers. These include British imperialism, the civilising influence of Christianity, and the importance of strong leadership. Ballantyne was a deeply religious man who felt he had a duty to educate Victorian youth in the ‘codes of honour, decency and religiosity’. The novel’s setting – on an untouched, pristine coral island – was no accident; it served as a metaphor for the paradise from which all mankind had fallen. According to the literary critic Frank Kermode, the novel is ‘a document in the history of ideas’, taking Darwin’s original theory and shaping it to the Victorian ideology of the superiority of white, western civilisation over the savages. As Ballantyne himself described it: ‘Britons at the top of the tree, savages and pigs at the bottom.’

And as such, The Coral Island was ripe for subversion. William Golding’s Lord of the Flies, published in 1954, took a much more Darwinian approach to the idea of the desert island and twisted Ballantyne’s paradise into a horrific dystopia, in which evil triumphs over good.

From his experience as a teacher, Golding was convinced that the idyllic events of The Coral Island could never exist in real life. So he wrote a novel that explored the darker side of human nature starting from the same basis of boys stranded on a desert island, away from all civilising influences. Things start going wrong immediately. Golding deliberately inverts Ballantyne’s moral code; even the book’s title is a literal translation of the name Beelzebub, another name for the devil. On this coral island, paradise has turned into hell. When the naval officer who comes to the rescue of the survivors at the end of the novel congratulates the boys on a ‘Jolly good show. Like the Coral Island’, what Golding was slyly suggesting was how badly we could misread evidence if we’d already decided on the story we wanted to hear. As Darwin pointed out in his monograph on coral reefs, while coral is beautiful, it remains a living organism, amorally determined to survive at all costs: ‘In an old-standing reef, the corals, which are so different in kind on different parts of it, are probably all adapted to the stations they occupy, and hold their places, like other organic beings, by a struggle one with another, and with external nature.’

Meanwhile, coral reefs have, like other natural phenomena, long been used and abused by advancing human civilisations. During the Spanish conquest of Central America in the late sixteenth and early seventeenth centuries, the Spanish built fortifications to defend themselves against what they regarded as ‘English pirates’ (the English preferred to refer to themselves as ‘privateers’). They did so by taking advantage of an abundant local resource: the coral reefs lying just offshore.

Known as ‘sea stones’, this hard, durable material proved ideal for construction, which continued for a further 200 years. One settlement in Panama, Portobelo, has been estimated to have used almost 13,000 cubic metres of coral, while the total amount of coral mined during the period has been estimated at more than 70,000 cubic metres. But along with the environmental damage, there was a human cost too, as Erica Hendy explains: ‘When they wanted to build the customs house at Portobelo slaves were sent out in canoes to the local reefs. Can you imagine grabbing these really sharp coral boulders the size of large crates out of the reef? Just as they can destroy a ship, they destroy your skin – it must have been a hellish job.’ The destruction of the reefs continued well into the twentieth century: during the construction of the Panama Canal, which opened in 1914, and during the 1960s, when roughly 5 million cubic metres of coral reefs were dredged to provide infill material for the construction of an oil refinery.

Over the centuries, coral reefs have been exploited for human gain in many other ways. Early coastal and marine civilisations benefited hugely from the abundance of fish around reefs, while collecting corals to make into jewellery also has a long pedigree. While these activities were only carried out on a small scale, they were sustainable; but even as early as Roman times there was a profitable trade in coral. Pliny the Elder observed that the Gauls were known to use it to decorate their helmets and weapons, while superstition led to Romans putting coral necklaces around children’s necks to keep them safe from danger; coral was also used as a cure for various diseases.

Coral continued to be harvested throughout the Middle Ages and afterwards, but it was only when big business became involved during the twentieth century that the damage to many reefs accelerated, in many cases becoming irreversible. One particular group, the red corals, have now become very scarce because of over-harvesting for jewellery, especially along the coastlines of Italy and other Mediterranean countries.

On a more positive note, chemicals extracted from corals are used in medicine, both traditional and modern forms; reefs have been described as ‘the medicine cabinets of the twenty-first century’. Compounds found in coral – which the corals themselves use as defences against predators – have been used to develop treatments for cancer, arthritis, heart disease and Alzheimer’s disease, among many others. Corals are even bred in captivity, either simply for pleasure, or as part of reef restoration programmes, in which specially grown corals can be used to repair damaged areas, or to ‘replant’ areas where the existing reef has been destroyed.

Perhaps the most fascinating tale of corals is that of Bikini Atoll, a group of twenty-three tiny islands covering an area of just 8.8 square kilometres in the Marshall Islands, roughly 2,000 kilometres north-east of Papua New Guinea, in the western Pacific Ocean. Bikini was catapulted into public attention in 1946 when the United States government chose this as the site to test its nuclear weapons.

The project, known as Operation Crossroads, aimed to test the effects of a nuclear explosion on ships and also on a range of animals placed within the blast zone, including guinea-pigs, mice and rats. Unfortunately the US authorities appeared to have ignored the fact that human beings also lived and worked on and around the reefs: so when the first blast went off, soon after dawn on 1 March, a boatload of Japanese tuna fishermen (whose craft was, ironically, named the Lucky Dragon) were within range of the explosion. Not sure what to do, the crew continued fishing for several hours afterwards, but by 10 a.m. extremely radioactive particles of coral dust were falling from the sky on to the deck of their boat.

They set off back to their home port, but on the way they began to suffer the effects of the nuclear fallout, including nausea, bleeding gums and headaches. They were immediately admitted to hospital, where the doctors – some of whom had treated survivors from Hiroshima and Nagasaki just a year earlier – diagnosed them as suffering from acute radiation poisoning. However the US authorities denied this. Less than a decade later, the Lucky Dragon’s radio operator, Aikichi Kuboyama, was dead at the age of just forty.

During the following twelve years, as the Cold War got into its swing, twenty-three nuclear bombs were detonated at the test site: some in the air, others on the ground or beneath the sea.

Since then the islands – which also, incidentally, gave their name to the two-piece swimsuit, rather tastelessly described by its creator Louis Réard as being ‘like the bomb … small and devastating’ – have remained uninhabited, as even after almost six decades the levels of radiation remain too high to be safe for permanent residents. However, scientists (and well-heeled scuba divers prepared to bring all their food with them and pay thousands of dollars for the privilege) are still able to visit the atoll where, despite the destruction caused by the bombs, corals are now flourishing in the mile-wide crater left by the biggest device. Ironically the reason the corals and sea life are doing so well is as a direct result of the lack of human interference here. UNESCO has now named Bikini a world heritage site:

Bikini Atoll has conserved direct tangible evidence that is highly significant in conveying the power of the nuclear tests, i.e. the sunken ships sent to the bottom of the lagoon by the tests in 1946 and the gigantic Bravo crater. Equivalent to 7,000 times the force of the Hiroshima bomb, the tests had major consequences on the geology and natural environment of Bikini Atoll and on the health of those who were exposed to radiation. Through its history, the atoll symbolises the dawn of the nuclear age, despite its paradoxical image of peace and of earthly paradise.

Elsewhere in the world’s oceans, corals have not been enjoying such protection. Although some have demonstrated an ability to ‘shift’ to deeper or cooler waters, many corals are unable to do so. As a result, roughly 10 per cent of the world’s coral reefs are now beyond saving, with many others – including large parts of the Great Barrier Reef – under threat. Sea temperature rises of just one to two degrees Celsius are enough to cause permanent destruction; so with some projections suggesting temperature rises of as much as four degrees by the end of this century, the future for the world’s coral reefs is looking bleak. In the worst affected region, South East Asia, four out of five reefs are now endangered, while globally it has been estimated that more than half the world’s coral reefs could be destroyed by 2030.

People are at least now far more aware of the beauty and fragility of coral reefs than they used to be, and this is thanks in no small part to a film. Finding Nemo, which first appeared in 2003, is an animation that tells the story of a young clownfish who, in an attempt to gain independence from his over-protective father, ends up leaving the safety of his home reef and gets lost in the vastness of the world’s oceans. Ralph Pite suggests that the success of Finding Nemo is because of the way it restores our original, primal view of coral reefs as an earthly paradise:

One of the striking things is that it goes back to the idea of the paradisal that we find in nineteenth-century accounts of coral reefs. There are moments in the film where the coral reef provides a kind of illuminated and sacrosanct space of safety and security. This is absolutely contiguous with the way authors such as R.M. Ballantyne wanted to portray coral islands.

Despite its good intentions, the film has had a mixed influence on the fate of coral reefs and the creatures that live there. On a positive note, it has raised awareness of the plight of this unique habitat. But another side effect of the film’s popularity led to a huge increase in demand for clownfish as pets.

This had two major environmental impacts. First, these dazzling orange fish with their black and white stripes were removed in vast numbers from their native reefs, with unscrupulous traders sometimes using cyanide to stun and capture them, causing the deaths of many other species left behind. Then, as a response to concern aired in the media, some aquarium owners decided to release their clownfish back into the wild. Unfortunately, they did so in entirely the wrong place, and as a result clownfish have now become a problematic invader, especially in Florida and California, where they can spread diseases and compete for food with native species.

Such is the tangled web we humans weave when we interact with the natural world. But the last word goes to Ralph Pite, who sees in corals and coral reefs something fundamental to our human need for a paradise here on earth:

So much of nature now is portrayed as a place of predation and cruelty and violence, with species warring with one another. This creates in us a sense of worry and danger, and the coral reef provides us with some counterweight to that. The science doesn’t bear that out – it suggests that there, as elsewhere, there is competition, predation and scarcity of resources – but what we see is something that fills us with that sense of reassurance that nature is full of beauty and comfort.

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Mammoth

Noun

1.

A large extinct elephant of the Pleistocene epoch, typically hairy with a sloping back and long curved tusks.

Adjective

2.

Huge.

‘A mammoth corporation’

Synonyms: huge, enormous, gigantic, giant, colossal, massive, vast, immense, mighty, stupendous, monumental, Herculean, epic, prodigious, mountainous, monstrous, titanic, towering, elephantine, king-sized, king-size, gargantuan, Brobdingnagian, mega, monster, whopping great, thumping, thumping great, humongous, jumbo, bumper, astronomical, astronomic, whacking, whacking great, ginormous.

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