Amazing facts about a dolphin.


A amazing of photo of a dolphin underwater.

The famous Delphic oracle was named after a dolphin (Greek, delphis), the form of which Apollo was said to have taken.

For a while dolphins were even associated with royalty, the crown prince of France being known as the dauphin (dolphin).

Stories about the dolphin’s playfulness and its willingness to save drowning humans have doubtless prompted a great deal of interest in this animal.

Some American aviators, who were shot down in the Pacific, however, were not very pleased with the help some dolphins gave them.

To their dismay, the dolphin rescuers pushed their life raft toward a Japanese-held island.

Nevertheless, until quite recently comparatively little was known about these amazing aquatic animals.

So we might take a closer look at them and see what we can learn.

Appearance


A dolphin jumping out of water.

Though outwardly resembling fish, dolphins are mammals.

They nurse their young, breathe air and maintain a constant body temperature very similar to that of humans.

Surprised?
.
Without a doubt, these animals are not quite what they appear to be!

A close look at the dolphin reveals some interesting differences between it and fish.

Search as you may, you will look in vain for gills.

But if you are observant, you will spot a small hole high on the dolphin’s back, just behind the head.

This is the animal’s single nostril; it does not use the prominent bill for breathing.

The holes just behind the eyes open up to a pair of ears so sensitive that they have been described as of a perfection unequaled in the animal kingdom.

Do you notice something different about the tail?

That’s right, it is horizontal rather than vertical, as in the case of fish.

Family life


A family of dolphins swimming together.

In every sense, the dolphin family is a large one, including such giant cousins as the 31-foot (9.5-meter) killer whale.

Why, even the smaller bottlenose dolphin can measure 10 to 13 feet (3 to 4 meters) in length and can weigh close to 900 pounds (409 kilos)!

Family relations are not exactly ideal.

The killer whale, for example, is likely to regard other relatives as a tasty snack!

Still, in their separate groups, members of the dolphin family enjoy fine community living, with large adults assuming the dominant role.

In the watery world of the dolphin, such family living has many advantages.

For instance, when a baby is born, it must surface rapidly to get its first breath.

Since the “baby” is a third of its mother’s length, it is a good thing that dolphin midwives are present to lend a flipper.

Yes, even “grandma” can get into the act.

But postnatal care does not end there.

At birth, both the mother and the new baby are surrounded by other members of the community.

They guard against any predatory sharks that might be attracted by the scent of blood.

If a shark should put in an appearance, he has a better chance of living to an old age if he quickly swims away without bothering anybody.

In a matter of minutes, sentinel dolphins can kill a shark by using their heads to butt the unwelcome intruder in the liver.

Each baby dolphin also has a “sitter.”

Along with the mother, this “sitter” assures that the baby will receive constant care and supervision.

Such care may include discipline when obedience is anything but instantaneous.

Dolphin mothers have been known to deal with a rambunctious youngster by taking it between their jaws and then either submerging it or holding it out of the water for about 30 seconds.

Usually one such “spanking” is sufficient to restore calm!

A wonderful swimmer


A dolphin swimming across the ocean.

Something that has long intrigued researchers is the speed with which dolphins can swim.

Calculations made as far back as 1938 indicated that the dolphin’s shape should permit speeds of up to only 12 miles (19 kilometers) per hour.

But these creatures are known to swim in excess of three times that speed!

How is such rapid movement, seemingly in defiance of hydrodynamic laws, possible?

Is it largely a matter of strength?

According to some reports, dolphins are six times as strong as a man, pound for pound.

But strength alone does not seem to be the prime factor in the dolphin’s swimming speed.

The key lies in the creature’s ability to pass through the water so smoothly that very little drag results.

This is attributable, not only to the manner of swimming, which eliminates any wake, but also to the dolphin’s remarkable skin.

Resting on a multitude of small, elastic supports, the skin acts as a shock absorber.

Also, a process known as “auto-obliteration” reduces surface friction.

When scraped or cut, the skin produces a grease that flows into the wound, restoring the animal’s streamlined surface and preventing further hemorrhaging.

One theory based on the dolphin’s rapid replacement of surface skin cells is that, when in a hurry, this creature “jumps out of its skin”—not literally, but by shedding skin cells to reduce the effect of drag!

As sea animals, dolphins must often plunge to great depths to catch their food.

They may spend more than five minutes at depths of 200 meters (656 feet) and then return rapidly to the surface to breathe.

For humans, a like feat is impossible.

This is not only because of the immense pressure encountered at such depths, but also because of the danger of getting the bends, often a fatal ailment caused by ambient pressure forcing nitrogen gas into a diver’s blood, making it “boil” if he surfaces too quickly.

What makes the humanly impossible possible for the dolphin?

There are several factors.

When diving, the dolphin’s heartbeat may slow down by as much as 50 percent, with only the brain, heart and other vital organs being supplied with oxygen.

This, in turn, lessens the need for air.

What is particularly interesting is that the dolphin can voluntarily empty its lungs of 90 percent of their contents, something impossible for humans.

Any remaining nitrogen is then absorbed by an emulsion produced in the lungs and is eliminated harmlessly when the animal surfaces to breathe.

As far as the crushing pressure is concerned, the dolphin’s rib cage is extremely elastic and, therefore, can be compressed in the depths without damage.

While humans cannot depend on seawater to support their body’s need for fluids, dolphins can.

Why is this?

Seawater contains 35 grams of salt per liter.

This is too much salt for human kidneys to handle; they are capable of removing only 22 grams.

Therefore, in the case of humans, drinking seawater just serves to increase thirst and hastens death by dehydration.

But dolphins experience no such difficulty.

Their kidneys, designed for an ocean environment, remove so much of the salt that they can drink seawater with impunity.

Another remarkable feature of the dolphin is its ability to stay warm in icy waters that, in only minutes, would kill even strong men.

Why is this?

The dolphin has the capacity to remain almost constantly in motion, even when resting.

Lolling near the surface and apparently sleeping, this animal will occasionally propel its head out of the water with a powerful tail stroke.

The action not only permits breathing, but also helps to generate needed heat.

However, this valuable heat would be dissipated rapidly were it not for two other built-in properties—a three-quarter-inch (2-centimeter) layer of insulating fat and the ability of the dolphin to restrict blood flow to the skin surface.

Then there is the astounding way in which the dolphin, despite its size and great speed, can avoid striking underwater obstacles.

This is partially attributed to the dolphin’s good eyesight.

However, keen vision cannot explain its skill in navigating and finding food at great depths in murky water.

There is evidence that the dolphin’s built-in sonar or echolocating system also helps the mammal to avoid obstacles.

By emitting a series of high-frequency whistles or clicks and then analyzing the echoes produced as the signals bounce off something, the dolphin can determine both the distance from and the nature of the object responsible for the echoes.

Since this animal does not have an olfactory organ and therefore cannot locate food by smell, its sonar system is vital for life.

Even when temporarily blinded during experiments, dolphins can infallibly differentiate between two varieties of fish of the same size and capture the one they prefer to eat.

So finely attuned is the dolphin’s ability to analyze returning signals that it can tell the difference between metal objects having identical dimensions but different density.

All of this with its eyes closed!

During experiments such as those just mentioned, researchers have been amazed by the dolphin’s ability to learn prompt obedience to human commands.

This explains why dolphins easily bond with human's

It our hope this bond will last an eternity