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Shark 

BellaOnline - 19 minutes ago
James Woods is directed by Spike Lee is Shark. A drama about a lawyer who want sto work at the LA high profile crime unit. This is the first TV drama for Woods. He was cut throat before he became a prosecutor and he is cut throat now. The high jinx begin on CBS.

Shark Meat Records to Release Grace Garland’s Holiday Anthem “Single Mingle Jingle” on October 31, 2006 
[Press Release] PR Web - 2 hours, 0 minute ago
Get Your Holiday On With Grace Garland. Dance Holiday Anthem Maxi-Single "Single Mingle Jingle" Featuring Remixes By Dr. Brooks To Be Released On Shark Meat Records. (PRWeb Oct 9, 2006) Trackback URL: http://www.prweb.com/chachingpr.html/Q291cC1FbXB0LVBpZ2ctRmFsdS1JbnNlLVplcm8=

Shark makes unwelcome competition appearance 
Independent Online - Oct 08 2:06 AM
A Great White shark - cruising close inshore - has forced organisers to temporarily halt the Kahuna Surf Series contest at Surfer's Corner in Muizenberg, Cape Town.

Shark disrupts surf contest 
iafrica.com - Oct 07 11:17 PM
A Great White shark cruising close inshore interrupted the first day's proceedings at the Kahuna Surf Series contest for novice surfers at Muizenberg Corner in Cape Town on Saturday, forcing the organisers to halt the event temporarily until the shark moved off.

sark

 

 

- shark

- sharks

?Sharks
Fossil range: Early Devonian sherk - Recent

Oceanic whitetip shark, Carcharhinus longimanus
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Chondrichthyes
Subclass: Elasmobranchii
Superorder: Selachimorpha
Orders

Carcharhiniformes
Heterodontiformes
Hexanchiformes
Lamniformes
Orectolobiformes
Pristiophoriformes
Squaliformes
Squatiniformes

Sharks Portal

Sharks (superorder zhark Selachimorpha) are fish with a full cartilaginous skeleton [1] and a streamlined sahrk body. They respire with the use of sjark five to seven gill slits. Sharks have a covering of dermal denticles to protect their skin shrk from damage, parasites and to improve fluid dynamics.[1] They have replaceable sharl teeth. They are some of the world's most misunderstood predators, as they never attack humans unless sharkk intimidated.

Sharks include species from the hand-sized pygmy shark, Euprotomicrus bispinatus, a deep sea species of only 22 cm in sharks length, to the whale shark, Rhincodon typus, the shark largest fish, which grows to a length of approximately 12 metres (41 feet) and which, like the great whales, feeds great white shark only on plankton through filter feeding. The bull shark, Carcharhinus leucas, is shark attacks the best known of several shark attack species to swim in both salt and fresh water (it is found in Lake Nicaragua, in great white sharks Central America) and in deltas.[2]

Contents

  • 1 Physical typer shark characteristics
    • 1.1 Skeleton
    • 1.2 Respiration
    • 1.3 Buoyancy
    • 1.4 Osmoregulation
    • 1.5 Teeth
    • 1.6 Tails
    • 1.7 Speed
    • 1.8 Dermal tiger shark whale shark denticles
    • 1.9 Body temperature
  • 2 Etymology
  • 3 Evolution
  • 4 Classification
  • 5 Reproduction
  • 6 Shark bull shark shark pictures hammerhead shark senses
    • 6.1 Sense of smell
    • 6.2 Sense of sight
    • 6.3 Sense of hearing
    • 6.4 Ampullae nurse shark of Lorenzini
    • 6.5 Lateral shark tale line
  • 7 Behavior
  • 8 Shark intelligence
  • 9 Shark sleep
  • 10 Shark goblin shark attacks
  • 11 Sharks in captivity
  • 12 Conservation
  • 13 Shark tiger sharks fishery
  • 14 Sharks in mythology
    • 14.1 Myths
  • 15 See basking shark also
    • 15.1 Films
  • 16 References
  • 17 External movie shark links

Physical characteristics

Main article: Physical characteristics of sharks

Skeleton

The skeleton shark tattoos of the shark is very different from that of bony fishes such as jump the shark cod; it is made from cartilage, which is very light and flexible, although the cartilage in shark bay older sharks can sometimes be partly calcified, making it harder and more bone-like. The shark's jaw is variable shark attack video and is walking shark thought to have evolved from the first gill arch. It is not shark fishing attached to the cranium and has extra mineral deposits to give it greater strength.[3]

Respiration

Like other shark tattoo fishes, sharks extract oxygen from seawater as it passes shark cartoon over their gills. Some sharks have a modified slit called a spiracle located just behind hammerhead sharks the eye, which is used in respiration.[4] Due to their size and the nature of their metabolism, many bala shark sharks have a higher demand for oxygen than bony fishes and they cannot megalodon shark rely on ambient water currents to shark teeth provide an adequate supply of oxygenated water. If these sharks were to stop lemon shark swimming, the water circulation would drop below the level necessary for respiration and the animal would suffocate. The process bull sharks of ensuring an adequate san jose sharks flow of the gills by forward movement is known as ram ventilation. Some sharks, such as the blacktip reef shark, Carcharhinus melanopterus, and shark bites nurse shark, Ginglymostoma cirratum, can cookie cutter shark pump water over their gills as they rest.

Buoyancy

Unlike bony fishes, sharks do not have gas-filled swim bladders, thresher shark but instead loan sharks rely on a large oil-filled liver (which may constitute up to 25% of their body mass)[5] for buoyancy. Its effectiveness is whale sharks limited, so sharks sink when they stop swimming. Some sharks, if facts about sharks inverted, enter a natural state of tonic immobility - researchers use pictures of sharks this condition for handling sharks safely.[6]

Osmoregulation

In contrast to bony fishes, sharks do not drink seawater; cartoon shark instead they retain high concentrations blue shark of waste chemicals in their body to change the diffusion gradient so that they can absorb water directly from the sea. shark vacuum This adaptation prevents most sharks from surviving in fresh water, and greenland shark they are therefore confined to a street sharks marine environment. A few exceptions to this rule exist, such as the bull shark, which has developed shark photos a way to change its kidney function to excrete shark attack footage large amounts of urea.[5]

Teeth

Tiger shark teeth

The teeth of carnivorous sharks are not attached to the jaw, but embedded in the flesh, largest great white shark and in many species are constantly replaced throughout the shark's life. All shark vacuum cleaner review sharks have multiple rows of teeth along the edges of finding a loan shark their upper and lower jaws. New teeth grow continuously in a groove shark vacuum cleaner replacement just inside the mouth and move forward from inside the mouth on a "conveyor belt" formed by great white shark pictures the skin in which they are anchored. In some sharks rows of teeth sand tiger shark are replaced every 8–10 days, while in other species they shark vacuum cleaner online could last several months. The lower teeth are primarily used largest shark for holding prey, while the upper ones are used for cutting into it.[4] The teeth range from thin, needle-like teeth for great white shark attacks gripping fish to large, flat teeth adapted for crushing shellfish.

Tails

The tails game shark codes (caudal fins) of sharks vary considerably between species and are adapted to the lifestyle of the shark. The tail provides thrust and pool shark so speed and acceleration is dependent angel shark on tail shape. Different tail shapes have evolved in sharks adapted for different environments. The tiger shark's tail megamouth shark has a large upper lobe which delivers the maximum amount of power for shark games that you can play slow cruising or sudden bursts of speed. The tiger shark has a the great white shark varied diet, and because of this it must be able to shark attack video clips twist and turn in the water easily when shark vacuum cleaner information hunting, whereas the porbeagle, which hunts schooling fishes such as mackerel and herring has a large lower cartoon sharks lobe to provide greater speed to help it keep pace with its fast-swimming prey.[7]

Some tail adaptations have purposes other than providing thrust. The cookiecutter shark has a tail with broad shark cartilage lower and borrow loan shark money upper lobes of similar shape which are luminescent and may help to lure prey towards the shark. The thresher feeds on fish and squid, which it shark clip art is believed to herd, then stun with its powerful and spined pygmy shark elongated upper lobe.

Speed

In general, sharks loan sharks online swim ("cruise") at an average speed of 8 km/h (5 mph), but when feeding or attacking, the average shark can reach speeds nurse sharks upwards of 19 km/h (12 mph). The shortfin mako may range shark fin upwards of 50 km/h (31 mph).[8] The shortfin mako shark is considered to be shark tale soundtrack the fastest shark and one of the fastest fish. The shark bite great white shark is also capable of considerable bursts of speed. These exceptions may be due to the shark costume "warm-blooded", or homeothermic, nature of these sharks' physiology.

Dermal denticles

Main article: shark week Dermal denticle

Unlike bony columbian sharks fishes, sharks have a complex dermal corset made of flexible collagenous fibres and arranged as a helical fast loan sharks network surrounding their body. This works as an outer killer sharks skeleton, providing attachment for their swimming muscles and thus saving energy. Their dermal teeth give them hydrodynamic advantages leopard shark as they reduce turbulence when swimming.

Body temperature

A few of the larger species, such as the shortfin mako, Isurus oxyrinchus, and types of sharks the great white, are mildly homeothermic [7] - able to maintain their body temperature above the surrounding water temperature. This loan shark is possible because of sharks teeth the presence of the rete mirabile, a counter current exchange mechanism that reduces the loss of body heat.

Etymology

Until the 16th century,[9] sharks were known to mariners as "sea dogs".[10] The name "shark" first came into salmon shark use around the late 1560s to refer to the large sharks of the shark attack videos Caribbean Sea, and later as a general term for all sharks. The name may have been derived from the Mayan word for shark, shark clipart xoc, pronounced "shock" or "shawk".

Evolution

A collection of fossilised shark teeth

The fossil record of sharks extends back over shark drawings 450 million years - before land vertebrates sharks pictures existed and before many plants had colonised the continents.[11] The shark attack pictures first sharks looked very different from modern shark gifts sharks.[12] The majority of the modern sharks can be traced back to around 100 million years ago.[13]

Mostly only the fossilized teeth of earthquakes and sharks sharks are found, although often in large numbers. In some cases pieces pic shark of the internal skeleton or even complete fossilized sharks have been discovered. Estimates rainbow sharks suggest that over a span of a few years a shark may grow tens shark logo of thousands of teeth, which explains the abundance of fossils. As the shark research teeth consist of mineral apatite (calcium phosphate), they are easily shark in wave fossilized.

Instead of bones, sharks have cartilagenous skeletons, sharks for sale with a bonelike layer broken up into thousands of isolated apatite prisms. When a shark dies, the decomposing skeleton big sharks breaks up and the apatite prisms property shark scatter. Complete shark skeletons are only preserved when rapid burial in bottom sediments occurs.

Among the most ancient and primitive sharks is Cladoselache, from reef shark about 370 shark facts million years ago,[12] which has been found within the Paleozoic strata of Ohio, Kentucky and Tennessee. At this point in the earth's shark tale: good foot history these rocks made up the soft black fin shark sediment of the bottom of a large, shallow ocean, black tip shark which stretched across much of North America. Cladoselache was only about 1 m long with card sharks stiff triangular fins and slender jaws.[12] Its teeth had several pointed cusps, which would zebra shark have been worn down by use. From the number of teeth found in any banded cat shark one place it is most likely that Cladoselache did bonnethead shark not replace its teeth as regularly as modern sharks. Its salt water sharks tank caudal fins had a similar shape to the pelagic makos and great white sharks. The discovery shark bait of whole fish found tail first in their stomachs suggest that they were shark tales fast swimmers with great agility.

From about 300 to 150 million years ago, most fossil sharks can be shark pics assigned to one of two groups. One of these, the xenocanths, was almost exclusive to freshwater environments. By bala sharks the time this group became extinct (about 220 freshwater sharks million years ago) they had achieved worldwide distribution. The other group, the hybodonts, appeared about 320 million sand sharks years ago and was mostly found in the oceans, but also in freshwater.

Modern sharks shark steamer began to appear about 100 million years unsecured loan shark ago.[13] Fossil mackerel shark teeth occurred in the Lower Cretaceous. The oldest white shark teeth shark steam cleaners date from 60 to 65 million years ago, aquarium sharks around the time of the extinction of the dinosaurs. In early white shark evolution there are at least two living megalodon shark lineages: one with coarsely serrated teeth that probably gave rise to the modern pet sharks great white shark, and another with shark cartoons finely serrated teeth and a tendency to attain gigantic proportions. This group includes the extinct megalodon, Carcharodon megalodon, which iridescent shark like all extinct sharks is only known from its teeth. A reproduction of shark coloring pages its jaws was based on some shark species of the largest teeth which up to almost 17 cm (7 in) long and suggested a fish that could shark tv show grow to a length of 25 to 30.5 m (80 to 100 ft). red tailed shark The reconstruction was found to be inaccurate, and estimates revised downwards to around 13 to shark anatomy 15.9 m (43 to 52 ft).

It is believed that the immense shark vacuums size of predatory sharks such as the great white may have arisen from the extinction of the carpet shark dinosaurs and the diversification of mammals. It is known that at shark carpet sweeper the same time these sharks were evolving some early mammalian groups evolved shark cordless sweeper into aquatic forms. Certainly, wherever the teeth of large sharks have been found, there has shark games also been an abundance of marine mammal bones, including seals, porpoises and whales. These bones frequently show signs shark helmets of shark attack. There are theories that suggest shark steam cleaner that large sharks evolved to better take advantage of larger prey.

Classification

Sharks belong to shark videos the superorder Selachimorpha in the subclass Elasmobranchii in angel loan shark the class Chondrichthyes. The Elasmobranchii also include rays and skates; the Chondrichthyes also include Chimaeras. It is currently thought that the sharks shark information form a polyphyletic group: in particular, some sharks are more closely related great white shark facts to rays than they are to shark tooth necklaces some other sharks.

There are more than 360 described species of sharks.

There are shark wallpaper eight orders of sharks, listed below in roughly their evolutionary relationship bruce the shark from more primitive to more modern species:

  • Hexanchiformes: Examples from this group include the cow sharks, frilled shark and even a shark that looks code game gold pokemon shark version on first inspection sharks of the maldives to be a marine snake.
  • Squaliformes: This group includes the bramble sharks, dogfish and roughsharks, and prickly shark.
  • Pristiophoriformes: These are the white sharks sawsharks, with an elongated, toothed snout that they use for slashing the fish baby shark that they eat.
  • Squatiniformes: Angel baby sharks sharks.
  • Heterodontiformes: They are generally referred to as the bullhead or horn sharks.
  • Orectolobiformes: They are shark art commonly referred to as the carpet sharks, including zebra sharks, nurse sharks, wobbegongs and the whale shark.
  • Carcharhiniformes: These shark replicas are commonly referred to as the groundsharks, and some of the species shark taxidermy include the blue, tiger, bull, reef and oceanic whitetip sharks (collectively called the requiem sharks) along with the houndsharks, catsharks and shark vacuum cleaner hammerhead sharks. They are sharks soccer distinguished by an elongated snout and a nictitating membrane which protects the eyes during an attack.
  • Lamniformes: They are swimming with sharks commonly known as the mackerel sharks. They include the goblin shark, basking thresher sharks shark, megamouth shark, the thresher world's largest sharks sharks, shortfin and longfin mako sharks, and great white shark. They are distinguished by their large jaws and ovoviviparous reproduction. The Lamniformes include the extinct a loan shark megalodon, Carcharodon megalodon.

Reproduction

Claspers of male spotted wobbegong, Orectolobus maculatus

The sex of sharks cartilage a shark can be easily determined. The males have modified pelvic fins the sharks of broadway which have become a pair of claspers. The name is somewhat misleading as they great white shark pics are not used to hold on to the female, but fulfill the role the mammalian penis.

Mating has rarely been observed grey nurse shark in sharks. The smaller catsharks often mate with the male curling grilling shark around the female. In less flexible species the two sharks swim parallel shark clips to each other while the male inserts a clasper shark tank into the female's oviduct. Females in many of the larger species have bite marks that aquarium sharks rays appear to be a result of a male common thresher shark grasping them to maintain position during mating. The bite marks may also pokemon pinball game shark code come from courtship behaviour: the male may bite the female to show his interest. In some species, females have evolved thicker skin to shark fishing rig withstand these bites.

Sharks have shark h a different reproductive strategy than most fishes. Instead of producing shark jaws huge numbers of eggs and fry (99.9% of which never reach sexual maturity in fishes which use shark recipe this strategy), sharks normally produce around a dozen pups (blue sharks have been recorded as producing shark skin twill 135 and some species produce as few as 2 code fantasy final game shark us x two).[14] These pups are either protected by egg cases or born bull sharks attack live. No shark species are known to provide post-natal parental protection for their young, but females have a hormone that inside of a shark is released into their blood during the pupping season that apparently keeps them from feeding on internet loan sharks their young.

Egg case of Port Jackson killer shark shark - found on Vincentia beach, Jervis Bay Territory, Australia

There are pokemon silver game shark codes three ways in shark chum which shark pups are born:

  • Oviparity - Some sharks lay eggs. In most of these species, the developing shark recipes embryo is protected by an egg case with the consistency shark steam cleaning of leather. Sometimes these cases are corkscrewed into crevices for protection. The mermaid's purse, found washed-up on beaches, is an empty egg case. Oviparous sharks shark vacuum cleaners include the horn shark, catshark, Port Jackson shark, whitetip reef shark and swellshark. [15]
  • Viviparity - These sharks maintain a placental link to the developing black shark young, more analogous to mammalian gestation than that of other fishes. final fantasy 8 game shark code The young are born alive and fully functional. Hammerheads, the requiem sharks (such as game pokemon saphire shark the bull and tiger sharks), the basking shark and the smooth dogfish fall great white shark attack into this category. Dogfish have the longest known gestation period of any shark, at 18 looking for loan sharks to 24 months. natal sharks Basking sharks and frilled sharks are likely to have even longer gestation pictures of killer whales attacking great white sharks periods, but accurate data is lacking.[14]
  • Ovoviviparity - Most sharks utilize this method. The young red tail shark are nourished by the yolk of their egg and by fluids shark vacuum filter replacement secreted by glands in the walls of the oviduct. The eggs hatch within the oviduct, and the young continue to be nourished by sharks in anguilla the remnants sharks in waves of the yolk and the oviduct's fluids. As in viviparity, the young are born alive and fully functional. Some species 8 cheat fantasy final game shark practice oophagy, where the first embryos to hatch eat the remaining eggs camden river sharks in the oviduct. This practice is believed to be present great white shark teeth in all lamniforme sharks, while the developing pups of the grey nurse shark take this a stage further and great white shark tooth necklace consume other developing embryos (intrauterine cannibalism). The survival strategy great white shark wallpaper for the species that are ovoviviparous is that the young are able to grow to leapard shark a comparatively larger size before being born. The whale shark is now considered to be in leopard sharks this category after long having been classified as oviparous. Whale shark eggs loan shark companies found are now thought package shark to have been aborted. Most ovoviviparous sharks give birth in sheltered areas, including bays, river mouths and shallow reefs. They choose such areas because of prince shark tennis racquet the protection from predators (mainly other sharks) and the abundance of food.

Shark senses

Sense of smell

Sharks have keen olfactory senses, with shark in a blue lagoon some species able to detect as little as one part per million of blood whale sharks in the golf of mexico in seawater. They are attracted to the chemicals found in the guts white shark photos of many species, and as a result often linger animated sharks near or in sewage outfalls. Some species, such as nurse sharks, have external barbels that greatly increase their megladon shark photos ability to sense shark attack in california prey. The short duct between the anterior and posterior nasal openings are not fused as in bony fishes.

Sharks generally shark eggs rely on their superior sense of smell to find prey, but at closer range they also shark movies use the lateral lines running along their sides to sense movement in the shark tatoos water, and also employ special sensory pores small shark on their heads (Ampullae of Lorenzini) to detect electrical fields created by prey and the shark net by robert drewe the ambient electric fields of the ocean.

Sense of sight

Shark eyes are tiger shark pictures similar to the eyes of other vertebrates, including similar lenses, corneas and retinas, though their eyesight is well adapted to the tribal shark marine environment all about sharks with the help of a tissue called tapetum lucidum. This tissue is behind the retina and reflects attack shark light back to the retina, thereby increasing bad consolidation credit debt loan new shark zealand visibility in the dark waters. The effectiveness of the tissue varies, with some sharks having stronger nocturnal adaptations. biggest shark ever Sharks have eyelids, but they do not blink because the surrounding water cleans their eyes. To giant sharks protect their eyes some have nictitating membranes. This membrane covers the eyes during predation, and when the how to make a shark puppet shark is being attacked. However, some jumping sharks species, including the great white shark (Carcharodon carcharias), do shark attack stories not have this membrane, but instead roll their eyes backwards to protect them when striking prey.

Sense of hearing

Sharks also have a sharp sense of hearing and can hear prey many miles away. shark tattoo pages A small opening on each side of their heads (not to be confused with the shark tooth identification spiracle) leads directly into the inner ear through a thin channel. The tiger shark golf clubs lateral line shows a similar blacktip shark arrangement, as it is open to the environment via a series of openings called lateral line pores. This card shark shoes is a reminder of the common origin of these two vibration- and greenland sharks sound-detecting organs that are grouped together as the acoustico-lateralis system. pokemon sapphire game shark code In bony fishes and tetrapods the external opening into the inner ear has been lost.

Ampullae of Lorenzini

Main article: Ampullae of Lorenzini
Electroreceptors (Ampullae of Lorenzini) and lateral line canals in the head of a shark.

The Ampullae of Lorenzini are the shark meat electroreceptor organs shark tooth of the shark, and they vary in number from a couple sharks attacks of hundred to thousands in an individual. The shark has the greatest electricity sensitivity known in all animals. This sharks in newfoundland waters sense is used to find prey hidden biggest shark in sand by detecting the electric fields inadvertently produced by all fish. It is this chemical shark repellent sense that sometimes confuses a shark into attacking a boat: when endangered sharks the metal interacts with salt water, the electrochemical potentials generated by the rusting metal are similar to the weak fields of prey, or in extinct sharks some cases, much stronger than the prey's electrical fields: strong enough to attract sharks gulf of mexico whale sharks from miles away. The oceanic pictures and 15 facts about sharks currents moving in the magnetic field of the earth also generate shark 1200 watt bagless convertible stick vacuum hepa electric fields that can be used by the sharks for orientation and navigation.

Lateral line

Main article: Lateral line

This system is found in most fish, including shark drawing sharks. It is used to detect motion or vibrations in the water. The shark uses shark identification this to detect the movements of other organisms, especially wounded fish. The shark can sense frequencies in the shark repellent range of 25 to 50 Hz.[16]

Behavior

Shark behaviour is inextricably linked to their senses as they influence every aspect of their lives. shark tale mp3 Studies on the behaviour of sharks have shark tale, get it together mp3 only recently been taken, leading to little information on the subject, sharks tale although this is changing. The classic view of the shark is of a whale sharks mexico solitary hunter, ranging the oceans in search of food; this is only true for a few species, 1963 corvett shark for sale with most living far more sedentary, benthic lives. Even solitary sharks meet for black tip reef shark breeding or on rich hunting grounds, which may lead them to cover thousands of miles in a year.[17] Migration patterns in cronulla sharks sharks may be even more complex than in birds, with many sharks covering how deadly is the great white shark entire ocean basins.

Some sharks can be highly social, remaining in large man eating sharks schools, sometimes up to over 100 individuals for scalloped hammerheads congregating around seamounts and islands in the Sea of Cortez.[5] Cross-species monster shark tournament social hierarchies exist with oceanic whitetip sharks dominating silky sharks or pacific sleeper shark comparable size when feeding.

When approached too closely some saw shark sharks will perform a threat display to warn off the prospective shark graphics predators.[18] This usually consists of exaggerated swimming movements, and can vary in intensity according to the level of threat. Although the display shark sweeper is not normally observed shark wallpapers during feeding, it resembles the action of a hard bite, and is believed to silky shark have derived from the feeding act itself.

Shark intelligence

Despite the common myth that sharks are instinct-driven "eating machines", recent studies have indicated that many species possess powerful problem-solving skills, social complexity baskin shark and curiosity. The brain-mass-to-body-mass ratios of sharks dogfish shark are similar to those of mammals and other higher vertebrate euro-pro shark 80 - 7133 review species.[19]

In 1987, near Smitswinkle Bay, South Africa, a group of up to seven great white sharks worked together to relocate freestyle shark watch the partially beached body hammerhead shark tattoo of a dead whale to deeper waters to feed.[20]

Sharks have heather boswell shark attack even been known to engage in playful activities (a trait also observed in cetaceans jumping the shark and primates). Porbeagle sharks have been seen repeatedly rolling in kelp and have even been observed kenny the shark chasing an individual trailing a piece behind them.[21]

Shark sleep

It is mud shark unclear how sharks sleep. Some sharks can lie on the bottom while actively poker shark pumping water over their gills, but their eyes remain open and actively follow divers. The spiny dogfish's pool shark vacuum spinal cord, rather than prince turbo shark tennis racquet its brain, coordinates swimming, so it is possible for a spiny dogfish to continue to swim while sleeping. It is also possible shark brain that a shark can sleep with only parts of its shark decals brain in a manner similar to dolphins.[22]

Shark attacks

Main article: shark filter internal Shark attack
Snorkeler with blacktip reef shark. In rare circumstances involving shark vacuum part poor visibility, blacktips may bite a human, mistaking it for prey. shark video Under normal conditions they are harmless and shy.

Contrary to popular belief, only a few sharks sharks and whales are dangerous to humans. Out of walking sharks more than 360 species, only four have been involved in a significant number of fatal, unprovoked angel sharks attacks on humans: the great white, buy six gill shark online tiger, oceanic whitetip and bull sharks.[23] These sharks, being large, powerful predators, may sometimes attack and kill people, car wash shark tale but all of these sharks have been filmed in open water, without the use charleston shark fishing of a protective cage.[24]

The perception of sharks as dangerous animals has been popularised by coral cat shark publicity given to a cow shark few isolated unprovoked attacks, such as the Jersey Shore Shark different types of sharks Attacks of 1916, and through popular fictional works about shark attacks, such as food web of shark the Jaws film series. The author of Jaws, Peter Benchley, had in his later years attempted free shark screensaver to dispel the image of sharks as man-eating monsters. In 2005, according to the greatwhite sharks International Shark Attack File, there were a total of 58 unprovoked attacks recorded worldwide, megladon shark of which four were fatal.[25] In comparison, several hundred modern great white shark teeth people die annually from lightning strikes[26] and 1.3 to pictures from be the creature great white shark 3 million people die from diseases transmitted via mosquito bites.[27]


Sharks in captivity

Two whale sharks in the Okinawa recent shark news Churaumi Aquarium

Until recently only a few benthic species of shark, such as hornsharks, leopard sharks and catsharks could survive in sandbar shark aquaria conditions for up to a year or more. This gave rise to shark cake the belief that sharks, as well as shark game being difficult to capture and transport, were shark records difficult to care for. A better knowledge of sharks has led to more species (including the shark skin large pelagic sharks) being able to be kept for far longer. At the same time, transportation techniques have improved and shark surfer now provide a way for the long distance movement shark tail of sharks.[28]

Despite controlled feeding shark theme behaviour being considered critical for the health of the shark, very few studies on this topic have been carried out. Since food is the reward sharks that walk for appropriate behaviour, trainers small sharks must rely on control of feeding motivation.

Conservation

The number tiger shark research of sharks being caught has increased rapidly over white tip reef shark the last 50 years.

The majority of shark fisheries around the amazing shark picture globe have little monitoring or management. With the rise in demand of shark products there is epaulette shark a greater pressure on fisheries.[29] Stocks decline and collapse because free pictures of sharks because sharks are long-lived apex predators with comparatively small populations, which makes it difficult for them breed game shark cheats rapidly enough to maintain population levels. Major declines in shark stocks have been recorded in recent years - great white shark photographs some species have been depleted largest great white shark caught by over 90% over the past 20-30 years with a mandalay bay shark reef population decline of 70% not being unusual.[30] Many governments and the UN have acknowledged the need for shark picture of the shark anatomy fisheries management, but due to the low pictures of great white sharks economic value of shark fisheries, the small volumes of products produced and the poor public image prehistoric shark teeth of sharks, little progress has been made.

Many other threats to sharks include habitat alteration, damage and radio shark loss from coastal developments, pollution and the impact recipes for grilling shark of fisheries on the seabed and prey species.

Shark fishery

Every year, an estimate states that 26 shark birthday party to 73 millon (median value is at 38 million) sharks are killed by people in commercial and recreational shark fins fishing.[31] In the past, sharks were shark icon killed simply for the sport of landing a good fighting fish (such as the shortfin mako shark mouth sharks). Shark skin shark picture is covered with dermal denticles, which are similar to tiny teeth, and was used for purposes similar shark sounds to sandpaper. Other sharks are hunted for food (Atlantic thresher, shortfin mako sharks for kids and others), and some species for other products.[32]

Sharks are stuffed sharks a common seafood in many places around the world, including Japan and Australia. In the type shark Australian State of Victoria shark is the most commonly used fish in fish and chips, in which fillets are battered typing shark and deep-fried or crumbed world record hammer head shark and grilled and served alongside chips. When served in fish and chip shops, it is called flake.

Sharks are often baby shark song killed for shark fin soup: the finning process involves capture of a live bagless shark vacuum shark, the removal of the fin with a hot metal blade, and the release blue shark charters of the live animal back into the water. There have been cases where cookie-cutter shark hundreds of de-finned sharks were swept up on local beaches without create my own shark monster any way to convey themselves back into the sea. Conservationists have campaigned for changes in the law to make facts on shark attacks finning illegal in goblin shark photo the U.S.

Sharks generally reach sexual maturity slowly and produce very few offspring in comparison to other fishes that are harvested. This has great hammerhead shark caused concern great white shark charters among biologists regarding the increase in effort applied to catching sharks over time, and many species are considered to great white shark wall paper be threatened.

Some organizations, such as the Shark irregular white spots dogfish spiny shark waters fin Trust, campaign to limit shark fishing.

Sharks in mythology

Sharks figure prominently in the Hawaiian mythology. There are stories of life cycle of a shark shark men who have shark jaws on their back. They could man and shark change form between shark and human at any time they desired. A common photos of sharks theme in the stories was that the shark men would warn beach-goers that sharks were in the rate shark deluxe upright vacuum hepa filter waters. The beach-goers recent shark attacks would laugh and ignore the warnings and go swimming, subsequently being eaten by the same shark man who warned them not to sea shark boat enter the water.

Hawaiian mythology also shark attack on surfer video contained many shark gods. They believed that sharks were guardians of the sea, and called them Aumakua:[33]

  • Kamohoali'i - shark attack statistics The best known and revered of the shark gods, he was the older and favored brother shark cordless vacuum of Pele,[34] and helped and journeyed with her shark dives to Hawaii. He was able to take on all human and fish forms. shark eating A summit cliff on the crater of Kilauea is considered shark helmet to be one of his most sacred spots. At one point he had a shark injector he'iau (temple or shrine) dedicated to him on every piece of land that jutted into the shark liver oil ocean on the island of Moloka'i.
  • Ka'ahupahau - This goddess was born human, with her shark outline defining characteristic being her red hair. She was later transformed into shark form shark punch and was believed to protect the people who lived on O'ahu from sharks. shark skeletons She was also shark steam floor cleaner believed to live near Pearl Harbor.
  • Kaholia Kane - This was the shark god of the ali'i Kalaniopu'u and he was shark tale car wash believed to live in a shark toys cave at Puhi, Kaua'i.
  • Kane'ae - The shark goddess who transformed into a human in order to experience the joy of dancing.
  • Kane'apua - Most silver capped shark tooth commonly, he was the brother of spiny dogfish shark waters fin Pele and Kamohoali'i. He was a trickster god who performed many heroic feats, including the calming of two legendary colliding the number of lemon shark attacks hills that destroyed canoes trying to pass between.
  • Kawelomahamahai'a - the sharks Another human, he was transformed into a shark.
  • Keali'ikau 'o Ka'u - He was the cousin of Pele tiger shark jet ski and son of Kua. He was called the protector of the Ka'u people. bamboo shark He had an affair with a human girl, who gave birth to buy sharks online a helpful green shark.
  • Kua - This was the main shark god of the codigos de game shark para medabots metabee version people of Ka'u, and believed to be their ancestor.
  • Kuhaimoana - He was the brother of fossil shark teeth Pele and lived in the free clipart sharks Ka'ula islet. He was said to be 30 fathoms (55 m) long and was the husband of Ka'ahupahau.
  • Kauhuhu - He was a great white shark photos fierce king shark that lived in a cave in hepa vacuum filters shark pursuit Kipahulu on the island of Maui. He sometimes moved to another cave on the windward side identifying shark teeth of island of Moloka'i.
  • Kane-i-kokala - A kind identifying sharks shark god that saved shipwrecked people by taking them to shore. The iridescent sharks people who worshipped him feared to eat, touch or cross the smoke of the kokala, his sacred fish.

In other Pacific Ocean lemon sharks cultures, Dakuwanga was a shark god who was the eater of lost souls.

In ancient Greece, octopus kills shark it was forbidden to eat painted sharks shark flesh at women's festivals.

Myths

A popular myth is that sharks are immune to pictures of tiger sharks disease and cancer; however, this is untrue. There are both diseases and parasites that affect sharks. The sale sharks evidence that sharks are at least resistant to cancer and disease is mostly anecdotal and there shark around have shark bite fittings been few, if any, scientific or statistical studies that have shown sharks to have shark diving heightened immunity to disease.[35]

See also

  • List of sharks

Films

  • Jaws (1975)
  • Deep Blue Sea (1999)
  • Open Water (2003)
  • Shark Tale (2004)

References

  1. ^ a b Budker, Paul (1971). The Life shark for sale of shark illustrations Sharks. London: Weidenfeld and Nicolson. SBN 297003070.
  2. ^ Allen, Thomas B. (1999). The Shark Almanac. New shark motorcycle helmets York: The Lyons Press. ISBN 1-55821-582-4.
  3. ^ Hamlett, W. C. (1999). Sharks, Skates and Rays: The shark silhouette Biology of Elasmobranch Fishes. Johns shark skeleton Hopkins University Press. ISBN 0801860482.
  4. ^ a b Gilbertson, Lance (1999). Zoology Laboratory Manual. New York: McGraw-Hill Companies, Inc.. ISBN 0-07-237716-X.
  5. ^ a b c Compagno, Leonard, Dando, Marc & Fowler, Sarah (2005). Sharks of sharks tooth the World. Collins Field Guides. ISBN 0007136102.
  6. ^ Pratt, H. L. silver shark Jr, Gruber, S. H.; sixgill shark & Taniuchi, T. (1990). Elasmobranchs as living resources: Advances in the biology, ecology, systematics, and the status snaggletooth shark of the fisheries. NOAA Tech Rept..
  7. ^ a b Nelson, Joseph S. (1994). Fishes of the World. New spiny dogfish shark York: John Wiley and Sons. ISBN 0-471-54713-1.
  8. ^ What's the Speediest Marine Creature?. Reefquest Center for sun shark Shark Research. Retrieved on 2006-09-12.
  9. ^ Online Etymology Dictionary. Retrieved the great white shark sunken vessel on 2006-08-08.
  10. ^ Marx, Robert F. (1990). The History of Underwater Exploration. Courier Dover Publications, 3. ISBN 0486264874.
  11. ^ Martin, the new york times 3a shark attack in florida R. Aidan.. Geologic Time. ReefQuest. 10 most dangerous sharks Retrieved on 2006-09-09.
  12. ^ a b c Martin, R. Aidan.. Ancient Sharks. ReefQuest. Retrieved on 2006-09-09.
  13. ^ a b Martin, bamboo sharks R. Aidan.. The Origin of Modern Sharks. ReefQuest. Retrieved on 2006-09-09.
  14. ^ a b Leonard J. V. Compagno (1984). Sharks of the World: An annotated and illustrated bull shark pics catalogue of shark species known to cape sharks pop warner date. Food and Agriculture Organization of the United Nations. ISBN 92-5-104543-7.
  15. ^ Marine Biology notes. School of Life Sciences, Napier University. Retrieved dinosaur shark on 2006-09-12.
  16. ^ Popper, A.N., C. Platt (1993). "Inner ear and lateral line". edible sharks The Physiology of Fishes (1st ed.).
  17. ^ Scientists track shark's 12,000-mile round-trip. Guardian fantasy sharks Unlimited. Retrieved on 2006-09-17.
  18. ^ Jaws: The natural history of florida shark attacks sharks. Natural History Museum. Retrieved on funny shark video clips 2006-09-17.
  19. ^ Smart sharks. BBC - Science and nature. Retrieved on 2006-08-07.
  20. ^ Is the White gory shark bites Shark Intelligent. ReefQuest Centre for Shark Research. Retrieved on 2006-08-07.
  21. ^ Biology of graet white shark the Porbeagle. ReefQuest Centre for Shark Research. Retrieved on 2006-08-07.
  22. ^ How great white shark fishing Do Sharks Swim When Asleep?. ReefQuest Centre for Shark Research. Retrieved on 2006-08-07.
  23. ^ Statistics on great white shark picture Attacking Species of Shark. ISAF. Retrieved on 2006-09-12.
  24. ^ Great white shark spotted off grilled shark recipes Hale'iwa. Hawaiian newspaper article. Retrieved on 2006-09-12. with pictures of cageless diver with great hammerhead shark tatoos white shark.
  25. ^ 2005 Worldwide Shark Attack Summary. ISAF. Retrieved how to draw sharks on 2006-09-12.
  26. ^ A Comparison with the Number of Lightning Fatalities in Coastal United States: kayak fishing for shark 1959-2004. Florida Museum of Natural History, University of Florida. Retrieved on 2006-09-12.
  27. ^ Campbell, Neil A., et mexico whale sharks al. new shark species (2005). Biology - Seventh edition. Menlo Park, CA: Addison Wesley Longman, Inc.. ISBN 0201434644.
  28. ^ Whale Sharks in Captivity. Retrieved on orca vs shark 2006-09-13.
  29. ^ Pratt, H. L. Jr., Gruber, S. H. & Taniuchi, T. (1990). Elasmobranchs as picture of a bull shark living resources: Advances in the biology, ecology, systematics, and the status of the record great white shark fisheries. NOAA Tech Rept. (90).
  30. ^ Walker, T.I. (1998). Shark Fisheries Management and shark and surfer Biology.
  31. ^ Triple Threat: World Fin Trade May Harvest up to 73 Million Sharks per Year. Retrieved shark attack .com on 2007-10-07.
  32. ^ FAO Shark Fisheries. Retrieved on 2006-09-10.
  33. ^ Hawaiian Mythology. Retrieved on 2006-09-13.
  34. ^ Pele, Goddess of Fire. shark attack game Retrieved on shark eggs for sale 2006-09-13.
  35. ^ Do Sharks Hold Secret to Human Cancer Fight?. National Geographic. Retrieved on 2006-09-08.
General references
  • Castro, Jose (1983). shark floor cleaner The Sharks of North American Waters. College Station: Texas A&M University Press. ISBN 0890961433.
  • Stevens, shark population John D. (1987). Sharks. New York: NY Facts on File Publications. ISBN sharks and minnows 1-858052-49-4.
  • Pough, F. H., Janis, C. M. & Heiser, J. B. silver tip sharks (2005). Vertebrate Life. 7th Ed.. New sleeper shark Jersey: Pearson Education Ltd.. ISBN 0-13-127836-3.

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