Sharks appeared on Earth more than 400 million years ago (the first dinosaurs emerged about 230 million years ago before becoming extinct 65 million years ago. The world’s first humans originated in Africa about 7 – 4 million years ago. Modern humans have evolved approximately 200,000 years.)
Sharks are extremely diverse cartilaginous fish. There are more than 440 species of sharks worldwide. Sharks come in a variety of shapes, colors, and sizes. The smallest is the Dwarf lantern shark (Etmopterus perryi Springer & Burgess, 1985), measuring about 17 cm, and the largest being the whale shark. shark (Rhincodon typus (Smith, 1828)) is about 20 meters in size.
The presence of sharks is a guarantee of the balance of the marine fish population structure. because as the highest rank hunter Sharks are responsible for eliminating slow, sick, or near-expired fish. Help select other species of fish to be strong. Maintain the balance of herbivorous fish populations at a moderate level without causing damage to their habitats. At the same time, it also controls the behaviour of smaller prey fish to stay erratic to allocate resources appropriately. Sharks are, therefore, very important to the marine ecosystem. It is no different with the importance of the existence of tigers in the wild.
What would the Ocean look like without sharks?
The depletion of sharks from the ecosystem has a chain effect on the food chain. Study on the importance of sharks to coral reefs in the Caribbean, it was found that when the highest predators like sharks disappeared, the number of second-level predators come down like a giant grouper will increase the amount until abnormal causing the hunt for herbivorous fish as well. When herbivorous fish such as parrotfish were greatly reduced; it will affect the control of algae; causing algae to expand in the ecosystem to compete for coral areas or cover up until the coral can’t compete; leading to the deterioration of coral reefs and caused a change in the ecosystem as a whole.
Another study off the coast of Carolina in the United States found that the fact that the blacktip reef shark was caught out too much. This has led to the collapse of traditional fisheries that have been catching scallops for more than a century because when there are no sharks, the cownose ray, the number one prey for blacktip sharks, is also growing rapidly and feed on large numbers of scallops until the scallop population disappeared from the area. There is no longer any fishermen left.
Source of photo: https://upload.wikimedia.org/wikipedia/commons/0/09/Argopecten_irradians.jpg
It’s not just coral reefs that need sharks. A study from Hawaii found that the presence of tiger sharks in seagrass reefs helped the sea turtles diversify, because of the tiger shark’s suspicion. Therefore, they are not very active in any one place. On the other hand, when tiger sharks run out of space Sea turtles graze in the same area comfortably without being cautious, causing damage to some areas of seagrass.
Sharks may look like bloodthirsty ferocious beasts. But in the real world, there is an amazing statistic: of the approximately 350 species of sharks worldwide, only 30 are potentially dangerous to humans, and only 4-5 the only kind that could be the one who attacked humans first. According to statistics, there are about 28-30 people attacked by sharks per year and there are no more than 10 deaths per year, which is less than people who are struck by lightning or stung by bees. Instead, sharks are being hunted and preyed upon by humans at least 100 million per year.