can a shark live with out swimming?
347164
YES! but that would depend on what species.\n\nsurprising to some, but NOT all sharks die when they stop moving. infact some species even tend to lie motionless at the bottom of underwater caves.\n\nCaribbean Reef Shark (Carcharhinus perezi)\nBanded Houndsharks (Triakis scyllium)\nWhitetip Reef Shark (Triaenodon obesus)\nLemon Sharks\nGrey Reef (Carcharhinus amblyrhynchos)\nBlackfin Reef (Carcharhinus melanopterus)\n\nare just a few examples.\n\nangel sharks lie motionless covered with sand on ocean floor to ambush prey.\nwhile some sharks "sleep"\n\nhope that helps :)
219522
The answer is a combination of several factors.\n\nThe skin is designed so as to limit "wrinkling" while swimming. (hydrodynamics) If u look at the skin closely, they consist of placoid scales which r smooth in one direction (swimming direction), and rough in the other direction.\n\nSharks r seriously buffed up, which aids in generating work.\n\nFins stabilise the body to prevent it from swimming upside down or in a circle\n\nThey belong to the chondrichthyes... cartilaginous fishes. This skeletal system is lighter than boney frames and allows for greater flexibility. Both characteristics COULD help in swimming. (There r, however, many fast marine animals with boney frames such as the dolphin or swordfish).\n\nThe tail is the main propulsion force. Which works in coordination with it's respiratory and circulatory system. As water passes over the gills, the lamellae r oxygenated, and at the same time release waste products (co2). So, if the shark swims slowly, the respiration rate decreases... and if he doesn't swim at all, he suffocates. I guess sharks swim fast because they have to. Haha. I hope that's helpful.
697945
Great Whites are a cold water shark. Yes you can find one off Rhode Island, though your chances get better the further north you go.. As for Australia being the place to go, not really. South Africa actually gives you better odds to dive with one as does the area around Patagonia, heck...anywhere the water temperature is 75 F to 55 F.
873464
sharks are really not as dangerous as there reputations shows them to be.  more people are killed by flying toilet seats every year than sharks while we kill over 100 MILLION sharks every year.  Now to answer your question, there is no real set of rules but there are guidelines you should follow\n1. don't swim alone\n2. always keep your eye on the shark\n3. do not wear jewelry or anything else shiny\n4. try to avoid the colors orange or yellow\n5. don't panic
721922
disagree  it's got to be a shark  and they don't have swim bladders
504128
Sharks do have backbones, as all vertebrates. Sharks do not have true bone, but their cartilaginous skeleton can be heavily calcified so that their vertebrae have the apperance of "bone" because they look like hard white cylindric spools. You might have seen their vertebrae made into necklaces and such by artisans. \nThis is what a shark trunk vertebra looks like:\nhttp://www.marinebiodiversity.ca/shark/english/porbeagle_vertebra__copy.jpg\nAnd without the neural and haemal arches they look like this: \nhttp://homepage.mac.com/mollet/Cm/BaskingSharkImages/basking%20shark%20vertebra%204.jpg\n\nAnd these are fragments of backbones:\nhttp://www.indonetwork.info/member/77806_backbone2.jpg\n\n(Notice the white color because the cartilage is calcified.)\n\nAlmost all the cartilaginous fish have backbones made of vertebrae (i.e. both sharks and skates/rays); the exception are the chimaeras or ratfish which do not have vertebrae, but retain a notochord (the primitive condition).
246558
That depends on the size of the shark and its scales. Shark scales are actually denticles embedded in the skin, with their point directed posteriorly. The morphology of these denticles is particular to each shark species, and in most cases, these denticles keep getting bigger as the animal grows (these skin denticles are shed and replaced just like sharks' teeth). \nSo, if you happen to rub with your naked skin against the shark, in the direction opposite that of the orientation of the denticle tips, you could get seriously grazed and chafed. \nAlthough many aboriginal cultures in different parts of the world have used shark teeth as knives, I've never heard of their skin used in this way. But the dry skin of some dogfish sharks was indeed commercialized as sandpaper, before the advent of artificial versions.
1043557
Relax, don't make any agitated movements, try and float horizontally.\n\nthe shark is attracted to movements and hence will go away if you do not thrash about.\n\nAlso, as its jaws are below its body, floatong flat makes it ver difficult for it to attack if uou are on the surface.
1010312
yes.\n\nthey are mammals and do not breathe underwater.\n\nthey take in air at the surface, so it does not matter what type of water they live in.
439262
I don't know anything about a "Sonic Shark Repellent". \n\nHowever, when you are diving in the Keys you should pay special attention to "current" and "wildlife".\n\nOcean currents can behave erratically when you are diving, especially around certain reefs. Just keep your "bearings" straight and you will be fine.\n\nDO NOT "handle" the wildlife. At some reef's the fish and "wildlife" will be quite "friendly". BE CAREFUL! Unless your qualified diving partner says its "OK" use the "LOOK BUT DON'T TOUCH" principle.( I don't want you to lose a hand or finger.)\n\nDO NOT touch the reef it-self. It is "un-cool"( and even illegal on some reef's), to "take a souvenir". Be happy with the experience of "the dive". Years ago my brother made the wrong decision to take some "cool looking red coral" as a souvenir. He wasn't wearing gloves. His hands swelled up like a balloon. Apparently, it was "Fire Coral",( that's what our guide told us later). \n\nJust make sure ,when you are in the water, to be aware of your surroundings; don't wear "flashy" watches or jewelry, and LISTEN TO YOUR GUIDE. \n\nObviously, you will want to wear appropriate "gear". And you should ALWAYS wear "booties" or "wet-shoes" when swimming,(coral can "eat" your feet up! Besides, you don't want to "kick-up" a Ray!) \n\nYou are going to have a blast! WISH I was going! Good Luck!
228732
Interesting question, but I think you're putting the cart before the horse. \nI could say that they don't live out of the water because their many specializations make it impossible; you've seen what happens when a whale gets beached. \n\nAnd why not turn the question around? Why not ask\n"If dolphins live in the water, why do they have lungs instead of gills?"\nThe thing is, adaptation is a phenomenon that usually shows us amazing results, such as the entire lifestyle of cetaceans (and they have many specializations for aquatic life). But a specialized or well-adapted animal is not "perfectly" fitted, because of the way evolutionary processes work. \nEvolution and natural selection can only work on the "materials" that are already there; and the lungs of mammals are not something that can be "reverted" to gills; their origin goes way back to remote ancestors of the whales. This irreversibility of _complex_ evolutionary processes is known as Dollo's "law" (and creationists love to misinterpret it). Stephen J. Gould gave a good example with the giant panda's "thumb" (this additional finger arose from one of the bones of the carp (wrist), and the real thumb of pandas is as reduced as in the rest of the Carnivora). \nEven if cetaceans where to evolve back into terrestrial animals, the results would not look like their ancestors, or probably anything that we know.
738330
feed my friend to the sharks while i swim away lol
631008
Sharks are boneless fish, so very primitive evolutionarily-they harken back a few hundred million years, without very much change- I seriously doubt, both because they are so primitive and havent changed in so long, that they have any remaining vestigial structures.  Generally vestigial structures come from an animal that has evolved from a quite different precursor-sharks are very close to the very first fish that evolved, thus they probably havent had to shed any organs or bones that arent useful.\nRibs? How is that vestigial?  They use their ribs for structural support, just like all fish...
29544
Sharks have two senses that many animals do not have:\n\nElectroreception: The Ampullae of Lorenzini are small pits in the head that detect electricity. The shark has the greatest electricity sensitivity known in all animals. This sense is used to find prey hidden in sand in bottom feeding sharks, by detecting the nerve impulses. It is this sense that sometimes confuses a shark into attacking a boat: when the metal interacts with salt water, sharks can detect the resultant electrical charge from over one mile away. \nLateral line - This system is found in most fishes, including sharks. It is used to detect motion or 'sound' in the water. The shark uses this to detect other organisms moving, especially wounded fish. The shark can 'hear' frequencies in the range of 25 to 50 Hz using this sense.\n\nHOW TO SWIM WITH SHARKS: A PRIMER \nVoltaire Cousteau\n\n\n--------------------------------------------------------------------------------\n\nForward\n\nActually, nobody wants to swim with sharks. It is not an acknowledged sport and it is neither enjoyable nor exhilarating. These instructions are written primarily for the benefit of those, who, by virtue of their occupation, find they must swim and find that the water is infested with sharks.\n\nIt is of obvious importance to learn that the waters are shark infested before commencing to swim. It is safe to say that this initial determination has already been made. If the waters were infested, the naïve swimmer is by now probably beyond help; at the very least, he has doubtless lost any interest in learning how to swim with sharks.\n\nFinally, swimming with sharks is like any other skill: It cannot be learned from books alone; the novice must practice in order to develop the skill. The following rules simply set forth the fundamental principles which, if followed will make it possible to survive while becoming expert through practice.\n\nRules\n\nAssume all unidentified fish are sharks. Not all sharks look like sharks, and some fish that are not sharks sometimes act like sharks. Unless you have witnessed docile behavior in the presence of shed blood on more than one occasion, it is best to assume an unknown species is a shark. Inexperienced swimmers have been badly mangled by assuming that docile behavior in the absence of blood indicates that the fish is not a shark. \nDo not bleed. It is a cardinal principle that if you are injured, either by accident or by intent, you must not bleed. Experience shows that bleeding prompts an even more aggressive attack and will often provoke the participation of sharks that are uninvolved or, as noted above, are usually docile. \nAdmittedly, it is difficult not to bleed when injured. Indeed, at first this may seem impossible. Diligent practice, however, will permit the experienced swimmer to sustain a serious laceration without bleeding and without even exhibiting any loss of composure. This hemostatic reflect can, in part, be conditioned, but there may be constitutional aspects as well. Those who cannot learn to control their bleeding should not attempt to swim with sharks, for the peril is too great. \nThe control of bleeding has a positive protective element for the swimmer. The shark will be confused as to whether or not his attack has injured you and confusion is to the swimmer's advantage. On the other hand, the shark may know he has injured you and be puzzled as to why you do not bleed or show distress. This also has a profound effect on sharks. They begin to question their own potency or, alternatively, believe the swimmer to have supernatural powers.\n\nCounter any aggression promptly. Sharks rarely attack a swimmer without warning. Usually there is some tentative, exploratory aggressive action. It is important that the swimmer recognize that this behavior is a prelude to an attack and takes prompt and vigorous remedial action. The appropriate countermove is a sharp blow to the nose. Almost invariably this will prevent
999898
only when it happens in the western hemisphere...during el nino while a hurrican blows in the month of july....wait of course they can they just say man-eating is because the women are smart to stay out of the water when there are sharks around...men say oooh...a shark let's go pet it. usually alchohol is involved with tha last part.
781518
Shark as long as i wasn't bleeding as they most likely wont attack unless you are. Where as lion's see meat and want to eat. Depends if they have been in capitivity for a while though because then i'd go in the cage because the lions would be used to humans and wouldnt attack and i don't really like fish.
655443
Sharks normally swim or live at a much deeper depth than dolphins. They do tend to share the same waters as far as proximity, although they do not get along very well.