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About This QuizMany shark attacks, while deadly, are mistakes. So why do sharks attack humans? And how can you avoid being mistaken for prey next time you're at the beach?
A shark is most likely to mistake a human on a surfboard for:
a beluga whale
a sea turtle
A shark swimming below the surface might see a roughly oval shape with arms and legs dangling off, paddling along. This bears a close resemblance to a sea turtle, a common food for tiger sharks.
Sharks detect the smell of blood in the water and the electrical impulses of a dying fish through sensors in their:
Sharks detect blood and other signals with their ampullae of Lorenzini, a set of detectors under the skin on a shark's snout. The ampullae are electrically sensitive cells that connect to the skin's surface through small tubes. They can lead a shark to mistake a human for a seal.
The majority of shark attacks:
occur after a shark stalks a surfer or swimmer for up to an hour, attacking only after its prey is alone
occur in the morning or early afternoon, as sharks are usually sleeping in the late afternoon or early evening
occur when a shark mistakes a human for its usual prey
Sharks usually eat sea turtles, seals, sea lions or whales, and there is no evidence that they have a natural appetite for humans. Most shark attacks on humans are mistakes -- the shark thinks it's attacking a sea creature. When it realizes it's not, it typically lets go and swims away. Unfortunately, by the time a shark realizes its mistake, the results can be lethal.
Great white sharks:
will usually attack and bite anything in the water, whether they think it's prey or not
are usually very picky about what they attack, refusing to bite anything that they don't think is prey
Contrary to their reputation in popular culture, great whites are actually very picky about what they eat -- refusing to bite things that are not their usual prey, such as floating sheep carcasses, after an initial taste.
usually attack prey as a display of dominance when they think another shark is acting too aggressively
Which of the following is true about shark attacks that occur in deep waters?
They are less common than attacks in shallow waters because sharks rarely swim at such depths.
They tend to be instances where the shark circles its prey before moving in, as opposed to most hit-and-run attacks.
While most shark attacks you hear about are hit-and-run -- a shark bites before realizing its mistake -- attacks at lower depths usually involve sharks circling the scene before moving in to attack.
They are more common than most shark attacks, because sharks are less cautious about losing their prey to other sharks at such depths.
Which of the following shark species demonstrates atypical attack behavior?
The bull shark is noted for its atypical attack behavior. It gets its name because of its persistence when attacking, often biting its prey, circling, biting again and repeating.
How many pounds per square inch can a shark generate with its teeth?
Sharks can generate an astonishing 40,000 pounds per square inch in jaw power, measured at the tip of the tooth. Their powerful bite can sever a human limb completely.
How do most attack victims die?
from sudden, traumatic injuries
from blood loss
Contrary to what most people think, most shark attack victims bleed to death, as it can take several minutes to bring a victim ashore and provide medical help. The difference between life and death is usually having someone at the scene who knows how to stop the blood loss.
from lethally low body temperature
What species of shark is considered the most dangerous?
great white sharks
Because of their unusual attacking habits and penchant for shallow coastal waters, bull sharks are considered the most dangerous. However, great white and tiger sharks are also among the most powerful and aggressive, residing at the top of the ocean food chain.
What U.S. state consistently has the most shark attacks?
Florida has consistently had the most attacks in the United States in the last two decades, with numbers since 1990 ranging from 10 to 37 per year. The U.S. tops the list for attacks worldwide.
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