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Nineteen centuries ago, Plutarch, a Greek moralist and biographer made this statement: “to the dolphin alone, beyond all other, nature has granted what the best philosophers seek: friendship for no advantage”.

In our own times Barbara Tufty made the comment “he also exhibits a friendly willingness to cooperate with other earth creatures — a rare attribute which another animal, Homo Sapiens, has not yet learned to do with any consistency”.2 Apparently there is something quite impressive about Dolphins. Not only now, when we are learning so much more about them, but even in the year 62 AD!

Outside of his striking friendliness, the Dolphin seems to have been blessed with a well developed sense of humor. Dolphins have been known to silently maneuver behind an unsuspecting pelican and snatch its tail feathers — usually leaving the bird minus a few. Other pranks include grabbing unsuspecting fish by the tail, pulling them backward a few feet as well as bothering slow turtles by rolling them over and over. Once a dolphin was seen placing a piece of squid near a grouper’s rock cranny. When the fish came out, the dolphin promptly snatched the bait away, leaving the puzzled fish behind.

Other pranks include grabbing unsuspecting fish by the tail, pulling them backward a few feet as well as bothering slow turtles by rolling them over and over. Once a dolphin was seen placing a piece of squid near a grouper’s rock cranny. When the fish came out, the dolphin promptly snatched the bait away, leaving the puzzled fish behind.

Do dolphins talk? Maybe. The above, the next two incidents, and the others scattered throughout this paper will probably lead you to the conclusion that they at least communicate with each other.

Jumping and playing

Dolphins occasionally leap above the water surface, sometimes performing acrobatic figures (e.g. the Spinner Dolphin).

Scientists are not always quite certain about the purpose of this behaviour and the reason for it may vary; it could be to locate schools of fish by looking at above-water signs like feeding birds, they could be communicating to other dolphins to join a hunt, attempting to dislodge parasites, or simply doing it for fun.

Play is a fairly important part of dolphins’ lives, and they can be observed playing with seaweed or play-fighting with other dolphins. At times they also harass other local creatures, like seabirds and turtles.

Dolphins also seem to enjoy riding waves and frequently ’surf’ coastal swells and the bow waves of boats. Occasionally, they’re also willing to playfully interact with human swimmers.

Sleeping

Because dolphins need to come up to the surface to breathe and have to be alert for possible predators, they do not sleep in the same way land mammals do.

Generally, dolphins sleep with only one brain hemisphere in slow-wave sleep at a time, thus maintaining some amount of consciousness required to breathe and keeping one eye open to keep a watch out for possible threats. The earlier stages of sleep can be observed in both hemispheres of the brain, however.

However, in captivity, dolphins have been observed to seemingly enter a fully asleep state where both eyes are closed and the animal does not respond to mild external stimuli, respiration being automatic with a tail kick reflex keeping the blowhole above the water.

If not needed to keep the blowhole above the water, the tail kick reflex may subside. Dolphins kept unconscious using anesthetics initially show a similar tail kick reflex. Though a similar state has been observed with wild Sperm Whales, it is not known if this state is ever reached in the wild amongst any dolphin species.

The Brain

The brain size of a bottle-nosed dolphin is comparable to ours at birth and, during their lifetime develops well into the upper levels of the maximum size for modern man — about 1700 grams.

A dolphin’s brain size increases very rapidly during youth and seems to slow down at nine years of age. This decrease is less than our slow down which occurs at our equivalent age of 17 years and afterwords.

Comparing dolphin’s brains to ours and others we can claim that it is deductible that dolphins could be intelligent enough to communicate.

Ever since the first time man ventured into the sea, dolphins have been man’s friend. Throughout history mentions are made showing this.

Dolphins have never in all our history been known to attack man — even when man tries to make him. The dolphin will resist even until his death. This alone leads me to believe that there is something superior in dolphins than in any other creature….including man. C.S. Lewis, in Perelandra (book two of his space trilogy), wrote about a planet where God had created two intelligent species….one that walked on the ground and one that swam in the oceans. What if…….

source : Wikipedia