DENIZENS OF THE SEA: CETACEANSIII
The daily trip to my workplace is a quick drive across the Mumbai – Agra Highway.
While traveling along this route, I have often witnessed the lonesome pariah dog and the typical chase that it gives a moving vehicle. This is habitually due to the playfulness of the canine rather than a hostile attitude. The drifting mariner, sailing across temperate and tropical waters, often has a similar experience with
dolphins. Moving in entire herds, nomadic dolphins follow ships for kilometers at a stretch, and while doing so, they display spectacular somersaults.
A somersault is second nature to this rather bouncy animal, probably because it is much smaller and lighter than most other whales. With bodies shaped like torpedoes, dolphins glide through water effortlessly, swiftly and ever so gently. Powerful tail fins called flukes propel dolphins through water while paddle-shaped flippers permit them to make sharp turns and halt abruptly in water. In spite of being gifted with the ability to dive deeply, dolphins do not appear to be very fond of doing so.
It is infact distressing to note that some dolphins die after swimming in very shallow waters and then, getting carelessly beached. These water-
mammals do not survive for long without water, as their bodies get over-heated. Most dolphins enjoy a life-span of 25 years while pilot whales are known to reach the age of 50 years.
Through the times, scientists have been mesmerized by studying these unusually stylish water-beings. An organ on top of the head enables them to make an entire range of sounds and they have even imitated human vocalizations! Enormously social and fairly friendly, they move in schools of 12 to 18 members.
Many aquariums and amusement parks across the globe have trained these animals to act in shows. These whales often invent behavior patterns and games by imitating other dolphins perform. To the awed spectators’ unmasked glee, they jump through hoops, chuck balls through nets and ‘walk’ backwards on the water surface. Some of them even leap 4 to 6 meters out of the water to ring a bell or snatch a fish out of a trainer’s grip! They even solve problems for themselves. A piece of food, stuck under a rock, is skillfully blown out and later, consumed.
The best known of all toothed whales, dolphins utilize their teeth to trap fish and squids. The killer whale, however, devours considerably large mammals.
A close relative of the dolphin, the porpoise, on the other hand, is not so intelligent. It also differs from the dolphin in the shape of head and teeth. With gently sloping foreheads, rounded snouts and spade-shaped teeth, porpoises roam the cool coastal waters of the Pacific and the Atlantic.
The interaction between dolphin and man goes back by centuries. Dolphins adorned ancient Greek coins, pottery and carvings. These mystical mammals were even a part of Greek and Roman mythology and were considered sacred to the Greek god, Apollo. In some parts of the world, the sailor is said to harbor a superstition that the sight of a dolphin is a sure indication of a safe voyage!
Swapna Datta Khan
Faculty, ICFAI, India