The body of a shark has been streamlined to allow a fast forward movement. Some of the shark species use their tails to propel themselves. For others, moving their bodies sideways and their fines maintain their balance.
The scales that act as the outer skeleton of the shark enhance their movement. They also help to regulate the energy they will use for their movement.
To initiate motion, a shark will use its tail to push water around the fins. The speed of the sharks differs depending on their body shape. Some of the sharks’ body shapes are cruisers, generalists, undulators, flappers, and wrigglers, among others.
Among all the fish species, sharks are the only ones that cannot swim backward. Their pectoral fin cannot bend upwards which limits their swimming ability to the forward movement.
If a shark wants to move backwards, it will depend on the gravity force to fall in the opposite direction. It is not possible for a shark to move in a backward motion.
If a shark attempts to move backward, water will get into their gills. This will tamper with the respiratory system leading to death.
The fishermen understand this fact and this is why they will pull a shark backward to kill it. With this, they will use little effort to overpower the shark.
A shark can never swim backward or even stop suddenly. If a situation arises and it has to move backward, it will sink backward.
Some of the sharks’ species must keep swimming in order to stay alive. If they stop, the supply of oxygen will be cut off leading to their death.
For others, they will be able to stay in the depth of the sea and still stay alive. Even when sleeping, they will move slowly to maintain the flow of oxygen.