Sharks, especially great whites, were catapulted into the public eye with the release of the film Jaws in the summer of 1975. The film is the story of a massive great white that terrorizes a seaside community, and the image of the cover alone—the exposed jaws of a massive shark rising upward in murky water—is enough to inject fear into the hearts of would-be swimmers. Other thrillers have perpetuated the theme of sharks as villans.
But where did our fear of sharks come from, and how far back does it go? That and other shark-related inquiries below.
"The question implies they shouldn't be," says David Ropeik, a consultant on risk perception and author of the book How Risky Is It, Really? Why Our Fears Don't Always Match the Facts.
A fear of sharks, or galeophobia, is not irrational, says marine biologist Blake Chapman, a shark expert at the University of Queensland in Australia. Simply put, the predatory fish are scary. Great whites, for example—the species Hollywood immortalized as mindless killers—have mouths lined with several rows of up to 300 dagger-like teeth that can easily shred through prey. They can also sense tiny electromagnetic fields put out into water by other animals, which helps them scope out their next meal.
But we're not necessarily afraid of sharks upfront, and the animals are diverse. There are more than 465 known species of sharks, and they can range in size from the 7-inch spined pygmy shark to the 50-foot-long whale shark. Many of these cartilaginous swimmers eat fish, crustaceans, mollusks, plankton, krill, marine mammals, and other sharks—in short, humans are not on the menu.
Rather, Ropeik says, we're terrified of how sharks could kill us. Being eaten alive by a 15-foot-long tiger shark seems like a painful way to suffer through death, and we dread the possibility that a shark attack could be the thing that kills us. You're more likely to be crushed to death under a falling vending machine in your office, or a cow that collapses on you in a field than you are to die in the jaws of a shark. But fears don't necessarily match facts, and the fear of being attacked by a shark is more about our emotional response than the reality. Most of all, we're afraid of losing control. If you're swimming in shark-inhabited water, you don't want the jaws of a mysterious predator to clamp down on you and determine your fate. "The idea of being munched on by an animal that is in control is another factor," Ropeik says. "It's the nature of the experience, and not the agent, per say."
Read More A school of fish might seem like a sea of identical faces, but at least one species has no problem telling its comrades—and even strangers—apart, new research says.To human eyes, which cannot see ultraviolet light, the Ambon damselfish (Pomacentrus amboinensis), appears yellow with a few spots. But to damselfish, which can see ultraviolet wavelengths, their fellow species sport a complex array of facial patterns that are unique to each individual. "The idea is that these patterns help the fish communicate secretly—without attracting the attention of predators, which, like us, are UV blind," says experiment leader Ulrike Siebeck of the University of Queensland, Australia. Scientists could see these patterns when they viewed the fish, native to coral reefs in the Western Pacific Ocean, through a camera with a filter that blocks all wavelengths of light except ultraviolet.
In experiments, Siebeck and colleagues found the 3.5-inch (9-centimeter) long damselfish can discriminate between individual faces of their own species and those of a similar species, the lemon damselfish. They could also tell the difference between different individuals of their own species. "I was amazed at how well these fish could discriminate facial patterns that were almost identical to my eyes," says Siebeck, who presented her preliminary results at the recent Behaviour 2015 conference held in Cairns, Australia. Face-Off For the experiments, Siebeck and her colleagues trained captive damselfish to associate a particular facial pattern, say, a stripe on the forehead, with a food reward. "The fish quickly learn to select rewarded targets placed in or behind their aquarium by swimming up to them," says Siebeck. "Initially we used printed and laminated pictures, but recently we moved on to presenting [the facial patterns] on a computer monitor located behind the aquarium.
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Sea scallops caught off the coast of England are capable of ingesting billions of tiny plastic particles, which disperse throughout the body to the kidney, gill, muscle and other organs. This all takes place within six hours. These findings are the latest in a growing collection of studies that confirm an ever-expanding roster of wildlife eats microplastics and smaller particles known as nanoplastics. That research, in turn, has raised questions—so far unanswered—about potential effects on the food chain, and to human health. What’s different and new is that this project attempts to get beyond documenting consumption and begin to understand the consequences for the wildlife whose diet now includes regular samplings of plastic. The surprise discovery was the rapid speed with which plastic particles spread across most major organs of the body.
Sea scallops caught off the coast of England are capable of ingesting billions of tiny plastic particles, which disperse throughout the body to the kidney, gill, muscle and other organs. This all takes place within six hours. These findings are the latest in a growing collection of studies that confirm an ever-expanding roster of wildlife eats microplastics and smaller particles known as nanoplastics. That research, in turn, has raised questions—so far unanswered—about potential effects on the food chain, and to human health. What’s different and new is that this project attempts to get beyond documenting consumption and begin to understand the consequences for the wildlife whose diet now includes regular samplings of plastic. The surprise discovery was the rapid speed with which plastic particles spread across most major organs of the body.
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