Most sharks have eight fins, which are made of cartilage. Their large dorsal fin provides balance, while the smaller ones are located closer to the tail. The pectoral fins help them steer and propel themselves. Here are some examples of what the fins of sharks do. Learn more about the different types of shark fins below. And, don’t forget to check out the rest of the article to learn about the different kinds of shark fins!
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Anal fins
An anal fin is a small, slender fin on the underside of a shark. It helps the shark stay stable in the water and prevents it from rolling sideways. Sharks also have a caudal fin, also called the tail, which helps them move forward. Sharks do not have an anal fin in all species. But they do have a similar function.
As they swim, sharks expend food and excrete waste. As do all animals, sharks poop after eating. The anal fin of some shark species acts like a boat’s keel. This makes high-speed cruising more energy-efficient. Sharks may have only one anal fin. In general, anal fins are triangular like the dorsal fin.
Caudal fins
The caudal fin on sharks has three distinct structures: the notochord, the anal fin, and the pelvic fin. The anal fin is located on the bottom of the body and provides stability for the entire body. The caudal fin, also called the tail, propels the entire shark forward, but not backwards. To turn away from an object, a shark must swish its caudal fin.
The caudal fins on sharks are asymmetric, making them ideal for maneuvering in water. This is the only animal group to maintain its asymmetrical tail profile for over 350 million years. Scientists are divided on the function of these fins, but some research suggests that they allow the shark to easily horizontally cruise. In any case, the caudal fin is a unique part of shark evolution.
Pectoral fins
We all know that sharks have pectoral fins, but what are the benefits and disadvantages of sharks having pectoral fins? Among those benefits, there is the fact that they are highly mobile. Their pectorals are not stiff like we might think. Recent film of White Sharks free-swimming has revealed that they can control and adjust their pectorals in a variety of ways. They can increase or decrease the angle of attack, and subtly curled, twisted, buckled, and bent.
Although sharks are highly versatile, each fin is specifically adapted to its habitat. Blue sharks and oceanic whitetips, for example, have long pectoral fins. Sharks use their pectoral fins to control their speed, decrease drag, and generate lift. Although pectoral fins are not used for swimming backwards, they are often used for social signals and display. These fins can even curled or buckled, which gives sharks precise control of their direction while swimming.
Pelvic fins
The pelvic fins of sharks have a variety of functions. In males, they function as a sperm intromitter by bearing a clasper made of modified radials. They also help in the growth of the young, which increases the chances of long-term survival. Unlike fish with a single, external fin, sharks have two sets of pelvic fins, a male and a female.
The pelvic fins of sharks are located on the underside of the animal, near the tail. Their main purpose is to stabilize the animal, allowing it to move forward. Not all shark species have pelvic fins, though. They are most commonly found in the great white shark and other large species. The pelvic fins of a wobbegong shark are flat and extend almost the entire length of the shark.
Dorsal fins
The dorsal fins of sharks look like moguls on a ski slope. That’s because sharks do not have proper arches or come to a decent point. However, modern viewers may not recognize the shark as a giant cat. In the film, the shark is freed by an octopus, a lady mouse, and a turtle. The giant shark dwarfs the turtle and scares the lady mouse.
Sharks and dolphins have very different dorsal fins. Dolphins have sharp fins, while sharks have curved ones. Compared to dolphins, sharks’ dorsal fins lie in parallel planes to the caudal fin. Although they are distantly related, sharks have different fins than dolphins. Dolphins have one dorsal fin and swim close to boats.