how dolphins defend their self?
970805
Head-butting, biting, drowning, and (I think) sonically (by emitting a loud sound focused at the enemy).
283592
They are part of the food chain for many species, whether it be at the beginning or in the middle. If dolphins disappeared, certain species would become over populated, and others would die off.
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Dolphins have to be conscious to breath. This means that they cannot go into a full deep sleep, because then they would suffocate. Dolphins have "solved" that by letting one half of their brain sleep at a time. This has been determined by doing EEG studies on dolphins. Dolphins sleep about 8 hours day in this fashion. \n\nA dolphin's behavior when sleeping/resting depends on the circumstances and possibly on individual preferences. They can either:\n1. swim slowly and surface every now and then for a breath\n2. rest at the surface with their blowhole exposed \n3. rest on the bottom (in shallow water) and rise to the surface every now and then to breath.
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.WHALES AND DOLPHINS:\n\nWhales and Dolphins are marine animals. They live in oceans around the world. Whales and Dolphins come from the same family, CETACEA (sey-tay-sha) . They both breath from a blowhole located at the top of their head. Whales and dolpins are mammals. They are mammals because they have lungs not gills,they have hair not scales , and they also have give live birth and don't lay eggs. There are only about 80 kinds of whales and dolphins that we know of right now.\n\nWHALES:\nWhales are very large animals. They can grow up to 100 ft. or more in length. They can weigh up to 200 tons or more. Whales live in families called pods. These pods vary in numbers and consist of family members and family friends. Whales live in these families their whole life. Group living is safer when other whales or sharks attack. It also makes it easier to find food. Whales are always migrating. They travel to find food, breed and have young.\nWhales do not have eyelids. They rely on thick oily tears to protect their eyes. Whales hear from little holes behind their eyes.\n\nWhales talk to each other by making high pitched sounds like whistles, clicks, squeaks, rattles, and groans.\n\nTo help protect the whales from extinction please DO NOT throw nets, fishing lures, or other fishing gear ocean\n\nDOLPHINS:\nDolphins live with the whales in the oceans. But dolphins come much closer to the shore. They will come as close to the shore as you or I can walk without going under water. Dolphins have teeth.\nLooking at a dolphin you would not think it as a nose, but surprise...it does! They have nostrils called blowholes. Over millions of years of evoloution whales and dolphins nostrils moved to the top of their head. This allows them to breath by surfacing instead of them sticking their whole head out of the water.\nThe first thing a newborn dolphin must do is to go to the surface to breathe. But the baby can not swim so its mother and a another dolphin will help push the baby to the surface for its first breath of air. The baby will be able to swim in about 30 min.\nDolphins are fast swimmers. When a speeding boat passes the bottlenose dolphin, it will start to race out in front . They will take off hitting the water and keep going.\nDolphins navigate by following the hills and mountains of the ocean floor, by tracking the sun, by sensing currents, and by tasting the water along the journey.\nA dolphin's sound probably originated in its nasal passages. These nasal passages are located on the top of the head. Dolphins can make sounds to see what lies ahead. This sense is called echolocations. The dolphins' sound waves hit an object and the echo bounces back. Echolocation sounds are called sprays. Sprays are so strong they can stun another whale. Dolphins don't "point" their melons at any other sealife except their enemies.\n\nSHARKS:\nOut of all the species walking, flying, slithering or swimming, there aren't many who have been around as long, survived as well, or come in so many shapes and kinds as the shark. The earliest evidences of sharks are isolated spines, teeth and scales that appeared about 430 million years ago in the Silurian Period, known as the "Age of Fishes". Sharks have a sleek, streamlined design which helps them swim without using up a lot of energy.They certainly need to conserve their energy because they never really sleep and most of them never stop swimming.\n\nSome sharks are fierce predators, and would be happy to eat you if they encountered you. Almost any shark six feet or longer is a potential danger, but three species have been identified repeatedly in attacks: the Great White Shark, the Tiger Shark and the Bull Shark . All three live world wide, reach large sizes and eat large prey such as marine mammals or sea turtles. But most sharks never grow longer than five feet and never even see anyone with legs and arms anyway. People kill thousands more sharks every year than sh
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They have breathing holes on their heads.When they need oxygen,they will swim onto the surface of the water and take in the oxygen.
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Dolphins have the vocal capabilities to talk like humans and communicate with us. It's true.
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chameleon, giant squid, wait... oh didn't see it all they all gone camouflaging...think that was a defense mechanism for them...
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Check a aquarium. Also, you can check the Internet and if you live near the coast, there is probably going to be some sort of research center nearby that would have people who know a lot of stuff about dolphins.\nCheck www.dolphins.org\nIt's a dolphin research center, I think.
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Dolphins might also have an itch, and that's the best way they can deal with it since they don't have hands.
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River dolphins, apparently.
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What is the difference between a dolphin and a porpoise? I heard this question asked, on Johnny Carson. And, Johnny decided that a dolphin was a mammal, and a porpoise was a fish. Wrong. They are both mammals, and are very closely related. The porpoises have a rounded head, while the dolphins have a protruding snout. They are smaller members of the toothed whale family, to which killer whales and sperm whales belong.\n\nTo complicate things, there are a couple of fish which are also called dolphins. I assume that these are sometimes called "dolphin fish" to avoid confusion. But, the well-known dolphins are those cute mammals, like Flipper (who is a bottle-nosed dolphin).\n\nMammals have hair, breath air, give birth to live babies (platypuses and echidnas lay eggs), and feed milk to their young. Whales breath air (they can hold their breaths for long times), give birth to live babies, and feed milk to their young. Where is their hair? Evidently, they have a small amount of hair around their blow-holes, those holes, in the top of their heads, that they breath through.\n\nThe toothed whales are among the most intelligent of all animals. The killer whale (orca) apparently has a brain mass to body mass ratio (a rough measure of intelligence) which is greater than that of humans. Incidentally, while toothed whales are predators, there is no record of any killer whale ever having killed a human being.
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It squirts an "ink" as a defense mechanism and uses it's arms to propel itself away.
100057
Dolphins represents knowledge.  And if you a colleting them, you have a strong desire to achieve knowledge!!!!  is that correct in your case!!!!???
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To avoid attack by sharks, never swim with a bleeding wound, which sends them into a psychotic feeding-frenzy, keep nearer the beach and a constant vigil for them, with other swimmers, and preferably a very nearby boat, and as sharks nudge and nibble to determine if something is edible, you have to strike them hard -kick, punch, heel of hand, elbow- them on the nose, as they have a very sensitive area full of nerve-endings there, and can be fazed for a few minutes by a strong strike.\n  Bears are territorial, and 'own' a big area!  The worst thing to do is startle a bear, sneaking up on them.  You should sing while you hike, walk with jingle-bells on your boots, play a radio, makes a lot of noise, and they will hide, and watch you.  Never make eye-contact, never start running to escape, they can catch Olympic sprinters!  Keep  a big pistol to hand.  The noise will scare most off, but the gun helps gives you a confident psychic trace, that they pick up on, rather than you quaking in your boots, wishing you had a gun! \nBee-stings kill a lot more than both.
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I recently saw a programme on National Geographic Channel where they showed many animals masturbating.  Can you believe that dolphins are pervs?LOL.I guess even animals need a little fun!
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Most 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 hearing underwater is also if not exclusively done with the lower jaw which conducts the 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. The dolphin's sense of touch is also well-developed.\n\nHowever, dolphins lack an olfactory nerve and thus have no sense of smell, but they can taste and do show preferences for certain kinds of fish. Since dolphins spend most of their time below the surface in the wild, just tasting the water could act in a manner analogous to a sense of smell.
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The core of a dolphin’s body is well insulated by a thick layer of blubber. Generally, a blubber layer is anywhere between 3/4" to 1-1 /4" thick. The thickness is related to the type of environment the dolphin lives in. Colder waters require a thicker blubber layer. The blubber is actually the modified 3rd layer or "hypodermis" of a dolphin’s skin. Skin is made up of three layers: an epidermis (top layer), a dermis (middle layer) and a hypodermis (bottom layer). The surface layer or epidermis of a dolphin’s skin is ten times thicker than any land mammal, and serves as protection against the elements. Additionally, the entire top layer of skin sloughs off every two to four hours, helping the dolphin stay streamlined, moist and while free of external attachments while traveling through the water.\n\nUpon close examination of a dolphin’s skin, micro dermal ridges are visible. Micro dermal ridges are small ridges that trap water molecules at the surface of the skin. This allows the dolphin to pass through its environment with less resistance because liquid moves more easily past another liquid than past a solid object. Micro dermal ridges allow a dolphin to travel more like a liquid through water with less resistance. A famous sail boat competitor used the idea of micro dermal ridges to his advantage to win the World’s Cup. He had Dupont design a skin for the bottom of his boat based on a dolphin’s micro dermal ridges. This technology increased his boating speed by a half-knot. Many wet suit companies use the principle of micro dermal ridges, as well.\n\nIn addition to micro dermal ridges, a dolphin has very pliant skin. When a dolphin reaches a certain speed while traveling through water, the typical smooth flow of water becomes more turbulent. A dolphin’s skin will actually ripple at accelerated speeds to counter the effect of turbulence as they travel through the water.