By Doug Pemberton

We pride ourselves on being one of the few animals on earth that can manipulate the raw materials around us in order to build a world that meets our needs and desires. Over the centuries our creativity, intelligence, insecurity and ego have resulted in the creation of some very impressive structures. We have built huge walls and fortresses to keep out our enemies, gigantic buildings to house ourselves and our gods, bridges and tunnels that have united countries, and monstrous dams that have forever altered the landscape. Not many species can match our accomplishments.

But 50 million years ago, long before man appeared and slapped together his first, crude, mud hut, blind, brainless, architects with no hands, and no blueprint to guide them, were busy creating some of the biggest, most intricate and impressive structures on earth. Human endeavours sometimes pale in comparison to the achievements of the tiny and fragile corals.

Diving the coral reefs of the world is a magical mystery tour through some of nature's finest work. Hundreds of species of corals, each with their distinctive size and shape, work in harmony to produce a landscape of huge castles, giant mushrooms, organ pipes or fields of tangled antlers.

But the animal responsible for all this beauty is really quite unimpressive at first glance. Little more than a hollow bag of jelly, they resemble their relative, the anemone, and are usually no more than 1/8 to 1/2 inch in size. Most are colonial but a few are solitary. A slit-shaped mouth at the top is rimmed by tentacles which contain stinging nematocysts. Hard corals may have six, twelve, or as many as 24 tentacles, where the soft corals usually have eight. The polyp lives and hides in a cuplike cavity in the coral called a calyx. During the day, many coral polyps withdraw into their limestone calices giving the coral a lifeless appearance, but when in bloom, they turn stone into a lush carpet of life and colour.

Corals have a varied diet that ranges from plankton to fecal pellets deposited by passing fish. In some corals, such as the bushy soft corals and fanlike gorgonians, the vertical structure of the colony allows the polyps to be filter feeders and strain out plankton and other drifting organisms from the water column. In many hard corals the tentacles may also be used occasionally for capturing prey or to manoeuvre a nice juicy fecal pellet into their mouths, but most of the reef building corals have a built-in food factory. Embedded within the body wall of the polyp are millions of microscopic, photosynthetic organisms, known as zooxanthellae. They live symbiotically, provide food and fuel and eagerly absorb many of the waste products of the polyp. But the relationship goes much further than just feeding. Without the zooxanthellae, the corals would not build reefs. It is the zooxanthellae that contains necessary chemicals for the adequate production of calcium carbonate. They are also responsible for providing much of the colour in some corals.

On one hand the corals are very fragile. The living layer of hard corals may only be 1/8 to 1/2 inch thick and a carelessly placed hand can obliterate a lifetime of work. But on the other hand they are incredibly resilient. In 1946, 42,000 men and 200 ships arrived on tiny Bikini atoll. The whole area was dusted with DDT, raw sewage along with chemical wastes from the ships and storage facilities was pumped into the waters. And as a final insult, two thermonuclear bombs were detonated. Several other lagoons suffered a similar or worse fate, but today coral can be found in these places, still continuing their age-old mission.

The sole purpose of many corals seems to be the secretion of calcium carbonate which results in the building of the reef but some corals seem to be there for an entirely different purpose. Large, bushy soft corals in dazzling shades of red, purple, orange or yellow add a vibrant splash of colour to many reefs. And huge lacy gorgonians or coral fans, with a span of ten feet or more, and in a variety of colours, seem to have no other purpose than to make us go "WOW".

Soft coral polyps sprout from a soft framework embedded with calcium carbonate spicules, giving the colony some rigidity while gorgonians, or fan corals, have polyps embedded in a soft layer of tissue that surrounds an internal woody stalk that contains gorgonin, a protein that resembles keratin, an ingredient in the formation of fingernails, hair and hooves.

Corals are usually associated with warmer waters and indeed, none of the reef-building corals occur outside tropical waters. But corals are found in all oceans and Canada's coasts are no exception. Corals are even found in the most unlikely of places. The Arctic is usually thought of in terms of ice, snow and wind. But beneath its freezing waters, bushes of the pink soft coral (Gersemia rubiformis) are found in abundance. The same coral is also found in the waters off the Atlantic and Pacific coasts of Canada.

Along the Pacific coast, small solitary cup corals are also a common sight. Encased in a stony skeleton that can be up to 3/4 of an inch across, lives a bright orange or yellow polyp. Gorgonian corals are also found in BC waters. For those with the training and equipment to plunge beyond recreational limits, a real treat awaits. In some areas of BC, a rare form of red gorgonian coral can be found. These fans can be a few feet in diameter and are an impressive sight. Smaller species of gorgonians can be found in shallower depths.

The corals are an amazing animal, incredible sculptors and architects and able to live under and withstand the harshest of conditions. And unlike human architects and builders who finish a project and move on, the coral reefs are a work in progress with hopefully no end in sight. Their presence and abilities are humbling and inspirational.