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Coral Reefs - Cities Under the Sea

As the most diverse ecosystem on earth, coral reefs possess an incredible array of interesting and bizarre creatures. The stories of their lives and relationships surpass the most creative science fiction and the ways in which communities organize themselves provide valuable lessons for those of us who search for sustainability.

The excerpts below offer a taste of the wonders of the reef and their relevance to humanity.

Product Details

  • Hardcover: 177 pages ; Dimensions (in inches): 0.75 x 10.25 x 10.50
  • Publisher: Darwin Pr; (October 2002)
  • ISBN: 087850138X

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Forward ....................................... 7
by Jean Michel Cousteau

Preface ........................................ 11

Acknowledgments ........................ 15

Introduction ................................. 16
Introduction [view]

Chapter One ................................. 21
Power Plants and Farms [view]

Chapter Two ................................. 33
Waste Managemnt and Recycling [view]

Chapter Three ............................... 43
Construction and Public Housing [view]

Chapter Four ................................. 69
PUblic Health [view]

Chapter Five ................................. 83
Conflict and Cooperation [view]

Chapter Six ................................... 103
Advertising [view]

Chapter Seven .............................. 117
Personal Lives [view]

Chapter Eight ............................... 135
Social Security [view]

Glossary ....................................... 157

Refrences ..................................... 163

List of Illustrations ......................... 169

Index ............................................ 173



The focus of this book is how a coral reef functions-the jobs of individual residents and how they collectively create a sustainable community. We will explore how corals construct the structure of this city under the sea..Coral reefs are, in many ways, like cities even though there are certainly many differences at many different levels of organization. By viewing coral reefs in the context of a city we can more easily see how they operate in ways that neither undermine their own survival nor that of others elsewhere; in other words, how the variety of species collectively enhances the survival of the entire community.

In the following pages we shall explore life in the coral city ... Ours will be an adventure of discovery. The subject matter is serious, but we will not take it so seriously that it won't be fun. When you finish I hope you will have a much better idea about how a coral reef functions and, based on this knowledge, how we might live a bit more gently on our planet.

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Chapter One: Power Plants and Farms

The coral city runs exclusively on solar energy. This is possible because almost all the surfaces of the coral reef are covered with solar collectors-various species of plants called algae. Some take the form of underwater farms and gardens; some are thin encrustations growing over the reef foundation; and others are the algae living inside corals. In fact, the form of many coral colonies is specially designed to promote efficient energy collection by algae..

...The high rates of productivity and efficiency of coral reefs are, in part, due to the architectural wisdom of corals themselves. Since sunlight comes down from above, solar collectors must be positioned on the top of the colony to receive it. To provide the greatest surface area for the absorption of sunlight, many corals flare into shapes resembling tabletops, arms reaching toward the sun, or leaves on a tree.

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Chapter Two: Power Plants and Farms

In the coral city there is no waste. The byproduct of every organism is a resource for another. This is seen in the relationship between corals and the algae that live inside the coral polyps.

Parrotfish: The Lawnmowers of the Reef Consider again the parrotfish that serve as lawnmowers by keeping algae from dominating the surface of the reef.. In the process of their grazing on algae or corals, the parrotfish may break off pieces of the calcium carbonate.

Ground up in the throat by molar-like pharyngeal teeth, this calcium carbonate is pulverized so that the organic matter can be digested. The inedible material then passes through the gut and is released as sand. In fact, a single two-foot parrotfish can produce a few hundred pounds of sand in one year. So, as you stroll along a pristine beach with "clean" white sand beneath your feet, remember where some of it came from and who to thank for it.

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Chapter Three: Construction and Public Housing

The Atoll. Although atolls are much less common than other reef forms, the story of their formation reflects the fascinating dynamics of how coral reefs grow. An atoll is a ring of coral reefs surrounding a large lagoon. When Charles Darwin was exploring the South Pacific in the mid-1830s, he noticed what seemed to be a gradual transition from recent volcanic islands with reefs close to shore, to islands where a ring of coral encircled an open lagoon, and finally to a ring of reefs surrounding a lagoon with no island at all. He speculated that the volcanic islands were the foundation on which corals grew and that through geologic time the islands sank, or subsided, until the island was totally submerged, leaving only a ring of coral. His theory remained just a theory until the 1960s when an accident of history moved scientific knowledge forward and proved him correct.. In other words, these drillings showed that on top of a large volcanic mountain, corals had created a huge limestone cap more than 4,600 feet high and that the top of this mountain had once been at the sea surface and subsequently subsided to the depth at which the coral-basalt interface was discovered. But the fact that the reef of Eniwetok is more than 20 miles in diameter suggests that height is much less noteworthy than the volume of this structure. The coral cap built from the calcareous remnants of the successive reefs has become a limestone structure of tremendous proportions. Eniwetok turns out to be more than ten times higher and at least 70,000 times larger by volume than the largest of the three pyramids (composed of the remains of onecelled planktonic animals called foraminifera) at Giza, near Cairo, Egypt ! A truly impressive structure created by "primitive" coral polyps."

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Chapter Four: Public Health

JUST ABOUT ALL living things are seen as a meal by some other life form. Not all predators, though, eat all their prey; some just nibble. This limited predation strategy insures the availability of future meals. ....

Reef Doctors
Coral-city residents are also vulnerable to predators, parasites, and diseases. Just as people get sick and go to a doctor for help, so do fish. ... These reef doctors are often called "cleaners"-shrimp and fish that "clean" their hosts of external parasites. Patients often must wait some time to be treated as there is great demand for health care, just as with our own doctors. Fish often line up, waiting their turn to be cleaned, and some reef doctors may see as many as 2,300 patients in one day. So much for bedside manners.

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Chapter Five: Conflict and Cooperation

Imagine you are walking through the inner city. You are alone, not particularly big, and not particularly tough. But you feel "ten feet tall and bullet-proof " with a can of mace in each hand. Or maybe you have a pit bull lashed to each arm. With such protection you're ready for almost anything or at least you're prepared to ward off an attack with these deterrents and, if nothing else, to buy a little time to flee from danger.

The boxer crab in the Indo-Pacific uses a similar strategy. These crabs hold an anemone in each pincer. When molested they thrust out their anemones just as a boxer puts up his fists. Tentacles of the anemones contain stinging capsules, so an adversary is met with the crab's bodyguards, a "fistfull" of anemones, each armed with chemical defenses.

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Chapter Six: Advertising

AS THE PACE OF LIFE in cities increases, communication often becomes reduced to condensed, highly visible messages. This is especially true in advertising, where simple visual symbols are designed to catch the eye and convey a clear and unmistakable message.

Danger-Watch Out!
Traffic signals, stop signs, poisons, and hazardous materials are all denoted with an easily recognizable symbol. Similar warning signs exist in the coral city. Many animals having venomous spines, poisons, or distasteful chemicals are brightly colored, often red or yellow. Such warnings, obviously, protect the animal but also protect predators from making a life-threatening mistake by preying on something that could be lethal.

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Chapter Seven: Personal Lives

WHETHER IT BE THE coral city or in a human city, there is no best way to earn a living. In both realms we see anincredible variety of strategies for survival and related adaptations. Beyond the basics of "eat and don't get eaten," there are endless variations on personal lifestyles-how to dress, attract a mate, commit to a relationship, raise a family, and so on.

Sex Lives
In most species of parrotfish, the young hatch from their eggs either as males or as females. But in some species, females can change gender to become males. These sex-changed individuals are called terminal-phase males or super-males. Supermales may look completely different from either females or individuals that began as males, called initial-phase males. Among the most dramatic examples of super-males is the stoplight parrotfis. Being able to change sex gives the species the ability to adjustmale-to-female ratios to maximize each individual's production of young. Since eggs are expensive and sperm is cheap, it is easier for a few males to fertilize a greater number of females. Consequently, it is safer to produce more females, and if a shortage of males occurs, some of the females change sex to fill in as needed.

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Chapter Eight: Social Security

What would life be like in a city based on the model of a coral reef ? First of all, it would be a place full of living things. All streets, sidewalks, and open spaces would be decorated with plants, but the natural decor would actually be edible and functional, as the plants would be producing fruits, vegetables, and useful materials such as wood, fibers, and medicines. In addition to products, trees and other vegetation provide other important functions such as taking up CO 2 and air pollutants, producing oxygen, and providing air conditioning through shade. In some areas community gardens would be maintained and protected by local residents. The buildings would be roofed with solar panels to provide energy and hot water for the community. All waste from the building's kitchens and toilets would be used to fertilize roof-top gardens or the edible landscaping. Lest all of those plants get out of hand, herbivores would act as natural lawnmowers controlling growth and converting plant production into animal resources of meat, fur, leather, milk, eggs, and so on.

Finally, perhaps the most important lesson to be learned from nature is that cooperation is essential in achieving sustainability. One very pragmatic reason is the realization of the interconnectedness of all species and even species and the environment-the premise that everything is connected. Any species, including Homo sapiens, that undermines the ecological integrity of the ecosystem undermines the security of its own future. In the human domain, pollution and over-exploitation of resources obviously undermine the quality of life for everyone, including generations to come. Whether it be at the invertebrate level on coral reefs, in the sophisticated social systems in dolphin societies, or in our major cities, all organisms are mutually dependent on one another through the roles they play in maintaining ecological integrity.

We should not let our fascination with individual members of the coral community and the details of their personal stories prevent us from an appreciation of the whole. An important message of this book is that everything is connected, and, as such, everything has a value in promoting the fantastic complexity that keeps the entire community functioning. This is relevant to coral reefs, human communities, and the planet. It means that our influence on the planet, particularly in the domain of habitat, biological species, and genetic diversity, is undermining the habitability of the planet for ourselves. Three and one-half billion years of evolutionary experimentation and design for survival have created a living system more wonderful, creative, beautiful, and inspirational than any human could have ever imagined. Whether one considers a rainforest or a coral reef or the entire planet, these living communities defy the "laws of entropy," running, adapting, and restoring themselves all by themselves, taking random units of non-living raw materials and converting them into magnificent living things. What a treasure to be cherished and protected.

My hope in exploring these great structures and fascinating ecosystems, the coral cities, is to convey some knowledge that will help us feel more connected to the reef and all other living creatures on this life-supporting oasis in space. It might even encourage some of us to help redesign our communities and the ways we live. Whether it be a human community, the coral reef, or the planet, biological diversity is social security. Protecting it is protecting ourselves.

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