Welcome to the Dolphin's Underwater World

IMAGINE for a moment that you're a dolphin. Think of yourself swimming with your eyes open to the sea. The water is your environment.

In early morning, a pod of dolphins moves swiftly through gold-tinted waters, their curving fins gilded by the rising sun. You are swimming with your pod, the large extended family of dolphins with whom you will share your life. There are different size pods, some small, some very large. Soon, your pod will be larger.

Rising and diving, rising and diving, the dolphins swim in a pattern across the sea: females together at the center, with new mothers and calves at the very heart of the pod. Young males swim near the outside, while the older males guard the edges, forming a wall of strength against sharks or orcas (killer whales), whatever is perceived as a threat.

You swim effortlessly, easily, in the cold water that foams over and under you, lifting you, so that you're weightless. Your skin is as soft as satin, firm and elastic to the touch. You shed your skin every two hours. The shedding is not visible, but if people were to touch you, they would feel a residue as fine as baby powder on their fingertips.

Suddenly, two female dolphins swim away from the others. A message passes through the pod. You taste it in the water. Slowing their movements, the dolphins in the pod begin swimming in wide circles, keeping the two females in sight.

Something exciting is about to happen: A dolphin calf is about to be born! While the mother dolphin is giving birth, the other female acts as midwife, watching in case there is trouble. The birth will take from 30 minutes to two hours, and the pod will remain close to protect the mother and baby.

The baby is born! He arrives flukes first to keep him from drowning. Quickly his mother pushes him up, up, up to the water's silvery surface and out into the fresh, clean air. He takes his first breath of life.

Dolphins are mammals, warm-blooded and needing oxygen from the air. The crescent-shaped hole at the top of his head is called a blowhole. It opens to let air in and closes to keep water out. Air passes from the blowhole through a channel and into the lungs.

In minutes, the baby swims alongside his mother as they rejoin the pod. Perfectly adapted to the sea, he is born knowing how to swim. Over the 60 million years since the dolphin was a land mammal, he has redesigned himself. What used to be hands have become flippers, each flipper containing the skeleton of a five-fingered hand. His ear is a tiny slit behind his eye, yet his sense of hearing does what man's combined senses of hearing, touch, sight, and taste do. He is perfectly adapted to his environment.

Within a week, when his tail and flukes have hardened, the new dolphin will be able to swim at 15 knots, or about 22 m.p.h., keeping up with the pod. He weighs about 25 pounds, and his head is too big for his body, but that will change as he grows. While he was born knowing how to swim, he has to be taught to move swiftly and smoothly. Now, each time he draws a breath, he pops out of the water like a cork. For his first six months, he'll live on his mother's milk. Then he'll learn to eat fish and to catch them.

The watery world is not a silent one. It is a world of sounds. Because his eyesight is not good under water, the dolphin uses his hearing to ``see'' by first making clicking noises and then using the echoes that return to locate obstacles in the sea. He can hear the ``snap'' of clams as they close, and the soft whisper of seaweed. He hears the thumping of ships' engines as they pass overhead, and the thin whistling of shrimps. Sometimes he hears the songs of the great whales as they pass in the deep pastures of the sea.

There are 47 species of dolphins in the world. The most familiar to us is the bottle-nosed dolphin (Tursiops truncatus) found in warm, shallow waters off the coast of the United States. Nature graced him with the dolphin ``smile,'' but what he doesn't have is what is needed to record history - a retractable thumb. He can't write, so he can't record the past - but he is very intelligent. The dolphin has no vocal chords, so the sounds he makes are unlike human speech. Yet he can imitate human speech patterns, echoing back what is said to him but in his own language.

But the universal language, the communication, is there, behind the dolphin's eyes. He speaks to us with joy. You look into a dolphin's eyes and you see, looking back at you, someone. Imagine wanting to talk to someone but you can't because you don't speak the same language. Still you try, with gestures and movement, with smiles and body language. The important thing is wanting to communicate.

Imagine you're a dolphin.

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