Buzz
Since the release of Jaws decades ago, sharks have been widely viewed as nothing but symbols of death and destruction beneath the waves. While great whites can be hazardous to humans, the vast majority of shark species have never attacked humans, whether provoked or not.
In reality, despite being portrayed as the ocean's deadliest creatures, sharks are not at the top of the food chain in our seas. The legend of the shark has been misrepresented and blown out of proportion over time, but the truth behind them is far more fascinating than the myths suggest.
10. Certain Sharks Are Bottom-Feeding Species
Sharks are often thought of as vicious, bloodthirsty hunters that relentlessly consume everything in the ocean. However, with over 400 known shark species, it may surprise you to learn that many of them don’t even pose a significant danger to smaller fish. Sharks aren't a major threat to humans because we're not their natural prey. When a shark does attack a human, it's usually because the animal has strayed far from its usual environment and made an error in judgment.
Many types of sharks are actually bottom-feeders, making them unlikely to pose a threat to humans, even by accident. There are also species of sharks that rely on filter feeding techniques for nourishment. Sharks like the whale shark, basking shark, and megamouth shark all use filter feeding, where they filter plankton from the water as food.
For even the largest sharks, dolphins can prove to be the most formidable adversaries. Dolphins often travel in groups and have been known to coordinate efforts to defend against shark attacks. Furthermore, dolphins are far from the docile, benevolent creatures we typically imagine. Studies have revealed that they tend to form groups, abduct fertile females from other pods, and even engage in aggressive behavior, such as raping males, to establish dominance.
9. Certain Sharks Can Halt Their Swimming
For a long time, it was believed that if a shark stopped swimming, it would suffocate and die in the water. However, the reality is more nuanced. Depending on how they breathe, some sharks are capable of stopping their movement.
Most sharks breathe using a process called “ram ventilation,” where they push water through their gills by swimming rapidly. However, other sharks use an older breathing technique, known as “buccal pumping,” which allows them to breathe while stationary. This process enables the shark to use its mouth muscles to draw water in for oxygen. Some sharks are “obligate ram ventilators” and cannot use buccal pumping. These species were once thought to perish if they stopped swimming. Nevertheless, researchers have occasionally observed obligate ram ventilators resting without any signs of distress, proving that they don't drown.
The practice of shark finning—where a shark is captured, its fin removed for shark fin soup, and the shark is then discarded back into the water—adds complexity to the issue of sharks drowning. Although it seems that removing a fin would lead to certain death, some finned sharks have been found alive (though in a malnourished state) during shark-catching events. Clearly, scientists still have much to discover about how sharks breathe.
8. Shark Attacks Are On the Rise But Are Still Exaggerated
According to the media, shark attacks saw an increase in 2015, especially along the coasts of North and South Carolina. Typically, there are only about six attacks each year in this region, but by early August 2015, there had already been 11. While some media outlets have compared this to a feeding frenzy, George H. Burgess, the head of the International Shark Attack File, penned an op-ed for CNN explaining the reasons behind the rise in shark attacks and why we shouldn't be overly concerned.
Burgess reassures us that the actual probability of being attacked by a shark is still about 1 in 11.5 million. He also notes that your chances of being struck by lightning are higher than being attacked by a shark.
More importantly, based on his extensive research as the director of the Florida Program for Shark Research at the Florida Museum of Natural History, Burgess believes that shark attacks are actually decreasing in percentage terms. The real issue, he points out, is the increase in the number of beachgoers. So even if the percentage of shark attacks is dropping, the total number of attacks is rising simply because there are more people in the water.
Additionally, drought conditions resulting from environmental changes can disrupt the balance of saltwater and freshwater, pushing sharks closer to shore than usual. However, Burgess argues that this risk can be minimized with simple common-sense precautions. He advises avoiding the water during dawn and dusk when sharks are most active, swimming in groups, and staying alert to your surroundings.
7. Sharks Are Not the Deadliest Predators in the Ocean
For many people raised on films like Jaws or Sharknado, large sharks such as the great white are often thought of as the undisputed kings of the ocean. Sharks are rarely considered prey. However, dolphins have long competed with sharks for dominance in the sea. While an average dolphin stands no chance against a great white shark, one species of dolphin can send almost anything in the water fleeing for its life.
That species is the orca, often called the “killer whale,” even though it’s actually a member of the dolphin family. By exploiting a vulnerability in sharks, orcas have been known to hunt, kill, and devour large sharks like mako and great white sharks.
Orcas employ two main strategies to accomplish this. By using its tail, the orca can generate currents to force the shark to the surface and then strike it with a tail slam. Alternatively, a pod of orcas can surround the shark and take turns attacking, often targeting the belly. Eventually, the orcas flip the shark upside down, inducing a state called “tonic immobility.” In this state, the shark stops resisting, making it easy prey for the orcas. While scientists aren’t entirely sure how orcas understand tonic immobility, they clearly know enough to hunt and feast on great white sharks.
6. Stressed Female Sharks Can Reproduce Without A Male
Parthenogenesis, a rare form of reproduction typically found in snakes and lizards, allows a female to produce offspring from an unfertilized egg without the involvement of male DNA. Researchers were astounded when a female hammerhead shark gave birth to a baby hammerhead despite having been isolated from males for three years at a Nebraska aquarium. Although females can store sperm, none have been known to retain it for such an extended period.
After closely examining the baby, which was tragically killed by another fish shortly after birth, scientists determined that the baby must have been conceived through parthenogenesis since it contained no male DNA. This discovery was a major breakthrough because it had previously been believed that sharks couldn't reproduce in this manner.
Not long after, an aquarium in Detroit reported similar cases involving their bamboo sharks. While it’s unclear whether parthenogenesis occurred with these sharks, the possibility seems likely. This suggests that numerous shark species may have the ability to reproduce without the need for male DNA.
Researchers believe that parthenogenesis occurs mainly in extreme situations, such as in captivity, where the animal has no other option for reproduction. While this could offer sharks an evolutionary advantage if their populations continue to shrink, it also has a significant downside. Parthenogenesis diminishes genetic diversity, which could harm the long-term survival of the species.
5. Sharks Are An Endangered Species
As previously mentioned, shark finning is a practice used to create shark fin soup, which is highly prized in parts of Asia. Often prepared for special events, such as marking a business achievement, shark fin soup has become a luxury item. Chef Gordon Ramsay famously commented that shark fin “tastes of nothing,” as it is used primarily for its texture. Despite this, the dish remains a deeply ingrained cultural tradition, making it difficult to eliminate.
Shark finning operations typically involve capturing a shark, slicing off its fin, and discarding the rest of the living animal back into the water, where it will slowly perish. While this is a death sentence for the shark, it is also wasteful, as the rest of the shark could be utilized. Many sharks also meet their end when caught in nets designed for other types of fish.
Several shark species are already on the brink of extinction, and experts fear that the future of global shark populations is at risk. While some may find it hard to empathize with sharks, they play a crucial role in our ecosystem. Their loss would have far-reaching consequences for many aspects of our environment. Conservation organizations are urgently working to protect sharks before they disappear, though the outcome remains uncertain.
4. Myths About Shark Cures For Cancer
You may have come across the idea that sharks are immune to cancer or that consuming shark cartilage can cure the disease. Even if sharks had better protection against cancer than humans, it's illogical to think that their natural defenses could simply be transferred to humans by eating their cartilage. However, there is a mix of truth and fiction surrounding these claims.
Some studies suggest that certain sharks produce a substance called 'squalamine,' which may be effective in fighting cancer. According to some clinical research, specific extracts from shark cartilage, when injected under medical supervision, could potentially aid in the battle against tumors. However, other experts argue that current evidence shows that sharks are no more resistant to cancer than cows or other animals.
While cancer is uncommon in sharks, Dr. Gary Ostrander, a biology professor at Johns Hopkins in 2003, warned that we shouldn’t assume that most sharks are cancer-resistant. Studying sharks in large numbers to determine their cancer susceptibility is challenging, as a sick shark is unlikely to survive long enough to be studied. Instead, it’s more likely to become prey for another predator. Additionally, scientists have discovered malignant tumors in sharks, even in their cartilage.
Even though shark cartilage might be touted as a cancer cure, ingesting it wouldn't be effective for humans because the body would not be able to deliver it to the bloodstream or target the tumors effectively.
3. Making a Shark Totally Defenseless Without the Aid of Tools
As mentioned earlier, orcas sometimes target large sharks, utilizing a defense mechanism known as 'tonic immobility' to improve their success rate. Divers and other specialists have also learned to use tonic immobility to ensure safety while studying or interacting with sharks. By flipping the shark upside down and holding it underwater, the shark remains completely still for several minutes.
Tonic immobility is an evolutionary defense mechanism in sharks, similar to feigning death. However, scientists are puzzled as to why a creature that sits near the top of the food chain would develop such a defense. The threats posed by humans and orcas are too recent to explain its development. One theory is that tonic immobility might be related to mating, but further evidence and research are needed to confirm this.
Despite this, orcas have recently discovered this weakness in sharks and are now exploiting it to their advantage. Sharks may not pose as much of a threat as many think, but the orca—the true apex predator of the seas—continues to evolve and become more intelligent.
2. Offering Human Sacrifices to the Shark Gods
In ancient times, certain cultures revered sharks, even considering them deities. Both Hawaii and India practiced worship of shark gods, which sometimes included human sacrifices in hopes of securing blessings and favors, as with any ritualistic prayers. In Hawaii, many of these gods had specific names, such as Kauhuhu, the ancient shark god.
Surprisingly, many of these shark-related sacrifices were voluntary, with followers willingly walking into the ocean to meet their fate. This was a common practice across different continents. Some accounts describe people being in a state of religious ecstasy as they offered themselves to the sharks. One tale recounts that the sharks, accustomed to feeding on the people rushing toward them, would be drawn to a mere shadow, and soon the waters would be stained red with blood.
1. The Hidden Dangers of Cage Diving
Following the success of films like Jaws, a massive industry emerged to fulfill the desires of those who wanted to experience the thrill of confronting a shark in real life, but in a safe environment. Today, businesses around the globe offer cage diving experiences that allow tourists to get an up-close view of these magnificent predators.
Cage diving involves tourists embarking on a boat trip, donning safety gear, and being lowered into a cage for protection while submerged. The tour operator then attracts a shark to the cage, allowing the people inside to enjoy the adrenaline rush of nearly being devoured. However, this practice also brings sharks closer to human-populated waters, which can increase their curiosity about humans and get them used to the presence of boats. In places like Australia, where this practice is widespread, there is concern that it may alter shark behavior, making them more aggressive toward humans.
On the flip side, tour operators are eager to expand their operations to new areas to sustain their profits. They argue that orca attacks have forced sharks to vacate certain regions, sometimes for extended periods, disrupting their business. This has sparked significant debate, and many people believe that before expanding further, more research should be conducted on the impact of cage diving on shark behavior.
