The article said shark's cells are all replaced over time instead of in our case getting older and less effective. So unless a disease or another predator takes them out, they could supply a long time with all required nutrients.
207381
Lets browse my X-files directory, hmm,....\nYeah, they could, as well as humans. But 'theoreically'..
86064
You are more likely to die in a car wreck than get eaten by a shark.  I want you to read the reference i attached.  If you think about it.  The are more people die in a peanut allergic than shark bites.
374691
i think you have to remember that the shark attacked the orca a number of times, and holed the orca so i can only assume that it had taken on so much water, that the sharks weight tipped the scales in it,s favour
581556
Actually- just because we are at the top of the food chain doesn't mean that we aren't still subject to selection pressures.  It is true that predation is one selection pressure that we no longer have to worry about, but disease is a selection pressure that we cant fully avoid.  \n\nWhile science has made tremendous progress in terms of preventing/curing "old-world" epidemics like polio and smallpox, new viruses and pathogens are constantly emerging through an evolutionary process of their own.... some diseases are such that they're only fatal to certain groups of people (for example, those with compromised immune systems), as well.  So theoretically, if such a disease were to grow out of control, those groups of people would be selected against...   \n\nAlso, culturally we're seeing that certain groups of people are reproducing more frequently and in greater numbers than others, while some populations have a negative birth rate.  If these sort of culturally-based reproduction trends continue, it's logical to assume that humans will look significantly different in the future. \n\nIt is safe to argue that we as a species have broken free of most of the evolutionary constraints that were once upon us- but there are still some factors that limit our evolutionary fitness.
151039
i think its because they feed on small fish that are visible from over the sea, or maybe they love what the humidity does to their hair/ feathers\naksugar06 what the hell are you talking about
435461
Water boarding wouldn't work.  You'd need to pull the fish out of the water and make it think it was dying that way.  Then they'd talk.  We have no choice but to use that technique, because some fish somewhere knows the details of a plot to explode a nuclear weapon on US soil.
72206
They could *be* shark teeth. There are plenty of places where you can pick them up right off the sand if you know where and how to look for them.
352272
I searched the ultimate source of all the stuff on net and here's what came out-\n\nhttp://scholar.google.com/scholar?q=humans%20and%20shark%20dna&hl=en&lr=&oi=scholart\nhttp://www.google.com/search?hl=en&q=humans+and+shark+dna\n\nGood luck
69089
No sharks do not sleep.  They must keep moving to stay alive.  This in turn also makes sharks the most pissed off creatures on the planet.  No wonder they're mean.
477899
As already stated, a shark would not be able to turn in it's own body length to attack itself.  I know this sounds gruesome, but I have seen a video of a disembowelled shark eating its own entrails time and time again until it died.  The shark was in a feeding frenzy.  So My answer would be if it could, it would!.
213544
There are sharks in all seas and oceans aaround the world. \n\nThere are many species of sharks found in the Mediterranean, especially in the western and central Med - including Hammerheads and Great Whites. Unfortunately the numbers of these sharks, of all sharks in the med, are in great decline and in many areas the numbers are close to non-existent. The culprit for this is commercial fishing (for blackfinn tuna and swordfish - both as a result of being caught in netsAND having their natural food sources depleted, in some cases to extinction - bluefin tuna became extinct in the Med in the 1940's)and, ironically enough, tourism. Especilly around Croatia in the late 90's there were several 'Jaws Tours'operating. The 'chumming' undertaken to attract sharks obviously attracted sharks into tourist areas which resulted in the culling of many, many sharks so as not to endanger tourism!\n\nSo, yes, there are sharks in the Med but I wouldn't be put of swimming in the Med as shark attacks here are almost non existent. Between 1508 and 2004 therewere a total of 38 shark attacks in European/Mediterranean waters. 18 of which were fatal with the last reported fatal shark attack being in 1984.  \n\nBut please get your friend to put the possibility of shark attack into persective. WORLDWIDE shark attacks between 1508 and 2004 totalled 1,986 of which 486 were fatal - in almost 500 YEARS! More people have been killed by deers running into their cars than by sharks!
89153
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.
49139
No- this is not possible as the viruses that cause these diseases need something alive to live off of so once an animal dies, the viruses that causes these diseases also dies.
124814
It could be that the body is trying to rid itself of toxins.
352353
The sharks may avoid these fish because their ancestors learned that those fish species are poisonous or just taste awful. Predators don't eat everything, just certain species. Take birds and butterflies. There are certain butterflies that have distinct patterns that birds recognize and the birds leave them alone because they are poisonous. Other butterfly species have similar patterns because they will get left alone if they look poisonous. The shark probably looks at the fish swimming in the tank and goes "I'm not eating that, you can't make me" and they wait for feeding time.
205520
if they are sick their sonar is off and they lose direction.  Often times, they end up on shore.  Perhaps it is natures way of weeding out the sick and weak.  Still very sad.
172543
Hope this sheds some light on it jessica.\n\n\nREPRODUCTION\n\nMost fishes are egg-layers, but many bear living young. Live-bearing fishes may be ovoviviparous, in which the eggs essentially simply hatch within the female, or viviparous, in which the unborn young are supplied nourishment through the mother's tissues. In some ovoviviparous fishes the embryo develops in the egg while the egg is still within its follicular covering within the ovary, and ovulation (or release of the egg) and birth occur at the same time. In other ovoviviparous forms the eggs are released from the protective follicles into the cavity of the hollow ovary, where development continues. In some viviparous fishes the walls of the egg follicle are in intimate contact with the embryo, supplying it with nourishment. In the viviparous sharks, a part of the oviduct, or egg channel, is developed into a uterus, where the modified yolk sacs of the young are closely joined to pockets within the uterus.\n\nIn live-bearing fishes and in some egg-layers, fertilization occurs internally, and methods have been evolved for introducing the sperm into the female's body. In sharks the pelvic fins of the male are modified into intromittent organs called myxoptergia, and in the male topminnows the anal fin is modified into a similar-functioning intromittent organ called the gonopodium.\n\nAt least three modes of reproduction--heterosexual, hermaphroditic, and parthenogenetic--are found in fishes. In the most common form, heterosexual reproduction, there are separate male and female parents, but even here there is considerable variation. In some live-bearing fishes, the female is able to store sperm for up to 8 or even 10 months, and this sperm is used to fertilize new batches of eggs as they develop. In some cases, a female may carry sperm from several males at once.\n\nIn hermaphroditic reproduction, a single fish is both male and female, produces both eggs and sperm (either at the same time or at different times), and mates with other similar hermaphroditic fishes. External self-fertilization occurs in one hermaphroditic fish, which sheds egg and sperm simultaneously. In another, internal self-fertilization may occur. In certain fishes there is a time sequence of hermaphroditism, young fishes reversing their sex as they grow older.\n\nIn parthenogenetic reproduction, unfertilized eggs develop into embryos. This is known to exist in at least one fish species, Poecilia formosa, of the Amazon River; however, even though development proceeds without fertilization in some of these females, mating with a male is still required to stimulate egg development.\n\nParental care also shows great diversity. Some fishes, like the Atlantic herring, form huge schools of males and females and freely shed their eggs and sperm (milt), and then abandon the eggs. Other fishes build nests and care for both the eggs and newly hatched young. Others have evolved methods of carrying the eggs with them, commonly in their mouths, but also in gill cavities or in special pouches on the body.