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Dolphin : One of mammal animal in the sea.

11:20 PM
Dolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in seventeen genera. They vary in size from 1.2 m (4 ft) and 40 kg (90 lb) (Maui's Dolphin), up to 9.5 m (30 ft) and 10 tonnes (9.8 LT; 11 ST) (the Orca or Killer Whale). They are found worldwide, mostly in the shallower seas of the continental shelves, and are carnivores, mostly eating fish and squid. The family Delphinidae is the largest in the Cetacea, and relatively recent: dolphins evolved about ten million years ago, during the Miocene. Dolphins are considered to be amongst the most intelligent of animals and their often friendly appearance and seemingly playful attitude have made them popular in human culture.
The name is originally from Ancient Greek δελφίς (delphís; "dolphin"), which was related to the Greek δελφύς (delphys; "womb"). The animal's name can therefore be interpreted as meaning "a 'fish' with a womb". The name was transmitted via the Latin delphinus, Middle Latin dolfinus and the Old French daulphin, which reintroduced the ph into the word.

The Dolphin Family and classifications :

Six species in the family Delphinidae are commonly called "whales" but are strictly speaking dolphins. They are sometimes called blackfish.


Common Dolphin
Bottlenose Dolphin
Spotted Dolphin
Commerson's Dolphin
Dusky Dolphin
Killer Whales, also known as Orcas
The Boto, or Amazon River Dolphin
Suborder Odontoceti, toothed whales

Dolphins, along with whales and porpoises, are descendants of terrestrial mammals, most likely of the Artiodactyl order. The ancestors of the modern day dolphins entered the water roughly fifty million years ago, in the Eocene epoch.

Hind Limb Buds on Dolphins An embryo of a Spotted Dolphin in the fifth week of development. The hind limbs are present as small bumps (hind limb buds) near the base of the tail. The pin is approximately 2.5 cm (1.0 in) long.
Bottlenose Dolphin with vestigial hind flippers, captured 2006 in Japan.

Modern dolphin skeletons have two small, rod-shaped pelvic bones thought to be vestigial hind limbs. In October 2006 an unusual Bottlenose Dolphin was captured in Japan; it had small fin on each side of its genital slit which scientists believe to be a more pronounced development of these vestigial hind limbs.

Dolphins have a streamlined fusiform body, adapted for fast swimming. The tail fin, called the fluke, is used for propulsion, while the pectoral fins together with the entire tail section provide directional control. The dorsal fin, in those species that have one, provides stability while swimming. Though it varies per species, basic colouration patterns are shades of grey usually with a lighter underside. It is often combined with lines and patches of different hue and contrast.

The head contains the melon, a round organ used for echolocation. In many species, the jaws are elongated, forming a distinct beak; for some species like the Bottlenose, there is a curved mouth which looks like a fixed smile. Teeth can be very numerous (up to two hundred and fifty) in several species. Dolphins breathe through a blowhole located on top of their head, with the trachea being anterior to the brain. The dolphin brain is large and highly complex and is different in structure from most land mammals. Unlike most mammals, dolphins do not have hair, but they are born with a few hairs around the tip of their rostrum which they lose shortly after birth, in some cases even before they are born.[ The only exception to this is the Boto river dolphin, which does have some small hairs on the rostrum.

Their reproductive organs are located on the underside of the body. Males have two slits, one concealing the penis and one further behind for the anus. The female has one genital slit, housing the vagina and the anus. A mammary slit is positioned on either side of the female's genital slitMost dolphins have acute eyesight, both in and out of the water, and their sense of hearing is superior to that of humans. Though they have a small ear opening on each side of their head, it is believed that hearing underwater is also if not exclusively done with the lower jaw which conducts the sound vibrations to the middle ear via a fat-filled cavity in the lower jaw bone. Hearing is also used for echolocation, which seems to be an ability all dolphins have. It is believed that their teeth are arranged in a way that works as an array or antenna to receive the incoming sound and make it easier for them to pinpoint the exact location of an object.

Now, Dolphins can helps as the therapy & healing for people. for example at Melka Excelsior Hotel Resort / Lovina - Bali.

The Bali Dolphin Therapy Centre that provides dolphin assisted therapy (DAT) and healing program to children & adults with paralysis, critical illnesses, disabilities, condition after stroke and special needs from all over the world.
We invite you to meet our therapist, learn about (DAT) dolphin assisted therapy
& healing, explore great resources for families and meet our dolphins in a peaceful atmosphere at the unique Melka Excelsior Hotel Resort on Bali Island.

Swimming with the dolphins is only a piece of the therapy. We will try to offer you more customized help.

To know if the client is ready to swim with the dolphins, you can try to swim in a normal pool and make him/ her float on the back with the head in the water. You can also practice this.This therapy program tries to involve the whole family if possible. Special attention or care can mean: relaxation, music, making art, play, horse riding, massages, balancing exercises (in the water). The longer time the client stays the more progress can be expected. For parents who come with children, we would appreciate their cooperation for the benefit of the child. Dolphins are characteristically very social creatures and often depend on social interaction for the purposes of hunting prey, defense and reproduction. Unlike humpbacks and other species of baleen whales, dolphins tend to form long-lasting groups that range in size from a few animals (2-40) called pods, to larger groups of up to several hundred members, known as schools or herds. Such groups may consist of more than one species, with little competition for resources, as each species occupies a different niche. Spotted dolphins and spinner dolphins are found living in such an association. Scientists believe this is possible because spotted dolphins tend to feed on larger species living near the surface, while spinner dolphins tend to feed at night on smaller species found in deeper waters. In Chile, some of the world's most endangered dolphins, the black dolphins, are hunted to provide bait for crab pots for the king crab industry. Catches of several thousand have been reported in recent years. Turkey has greatly reduced dolphin populations in the Black Sea to produce oil and chicken feed. In the Faroe Islands and parts of Asia, a type of fishing known as "drive fishing" has been practiced for centuries by fishermen who view the fish-eating marine mammals as competition for their catch. The fishermen use boats and large nets to "drive" schools of dolphins into shallow bays and harbors where they are killed, often brutally. The meat is often sold for human or animal consumption, or made into fertilizer. Japan is believed to be the largest consumer of dolphin.

Each year thousands of people around the world are introduced to dolphins and the problems they currently face through their visits to aquariums, zoos and marine parks. Education can be a very powerful tool as learning about a particular animal is often the first step towards becoming active in its conservation. As noted dolphin researcher Ken Norris states, "Our knowledge of these dolphins is their protection. You cannot kill what you come to love."
Public education is proving effective in some places where dolphins had traditionally been considered to be undesirable predators or competition to fishermen. Changes in public sentiment towards dolphins and other marine mammals have occurred as a result of people learning more about them. Once public sentiment changes, political sentiment is often soon to follow, bringing about the establishment new laws and regulations needed to protect species. There are many legal conservation which has protected the dolphin. In the United States dolphins are protected under the Marine Mammal Protection Act (MMPA) which prohibits the hunting, harming or harassing of any marine mammal by any person under legal jurisdiction of the United States (see Appendix 2 for more detailed information on and MMPA) and under the International Dolphin Conservation Act of 1992. The International Dolphin Conservation Act (IDCA) is a federal law passed by Congress in 1992 that is designed to bring about a rapid phase-out of all purse-seines set on schools of dolphins. The way the Act is designed to work is by providing countries that are currently purse-seining on dolphins with economic incentives to stop. and International protection of dolphin species considered to be endangered or threatened is provided under CITES, the Convention on International Trade of Endangered Species of Wild Fauna and Flora .

After all we must keep protect their population to keep the mammals animal in the sea.
Dolphins
Fossil range: Early Miocene - Recent
Bottlenose Dolphin breaching in the bow wave of a boat
Bottlenose Dolphin breaching in the bow wave of a boat
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Cetacea
Suborder: Odontoceti

Source : Wikipedia
earthtrust.org

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