Sharks are known for their powerful jaws and razor-sharp teeth.
They also possess some amazing abilities such as being able to swim backward and even change direction mid-swim.
Can they really stop moving?
According to shark experts, sharks can indeed stop swimming.
This ability helps them conserve energy and stay out of harm’s way – we took a closer look at the truth behind this claim, and the reasons why sharks may decide to stop swimming.
What Are Sharks?
Sharks are fish that belong to the class Chondrichthyes (cartilaginous fishes).
The word “shark” derives from the Old English scearac, which means “a sea raven.”
There are over 400 species of sharks in the world, but only about 40 of these live in freshwater.
Shark scientists use four main characteristics to identify different types of sharks: the shape of the head, number of gill slits, the structure of fins, and pattern of tooth rings.
How Do Sharks Swim?
Like all fish, sharks have two sets of paired fins on either side of their bodies, and these consist of pectoral fins, dorsal fins, ventral fins, anal fins, caudal fins, and tail fins.
When sharks move through water, they use their pectorals to push themselves forward using pressure gradients.
The caudal fin is used to steer and balance the animal while it moves forwards.
Sharks’ tails are made up of skin, muscle, blood vessels, nerves, and connective tissue.
Their tails help them propel themselves through the water by creating waves called propulsive vortices.
These vortices create thrust forces that push the shark forward.
The dorsal fin is located just above the back end of the body.
It serves as an airfoil, allowing the shark to glide through the water.
The dorsal fin has a very important function in helping sharks to swim in a straight line, as it works to keep the shark stable in its position, and acts almost as a downward boat stabilizer.
Do Sharks Die If They Stop Swimming?
There is a common belief that sharks will die if they stop swimming, but the situation is not quite as simple as this.
It is true that the majority of sharks need to be constantly moving forward throughout the course of their lives, as this helps them to continue to breathe.
Sharks take in oxygen through their gills, which are located near the top of their heads.
Gills allow sharks to extract oxygen directly from the surrounding water. In order to extract enough oxygen from the water, sharks must continuously swim.
To understand why sharks must constantly move, we need to first understand how they breathe. Sharks breathe by taking in seawater through their gills.
Once inside the gills, the seawater passes through capillary beds where it picks up oxygen.
Then, the oxygenated water travels along the length of the shark’s gills before leaving the body via the olfactory organ.
Once the oxygenated water leaves the shark’s body, it returns to the ocean, carrying with it the carbon dioxide produced during respiration.
This process allows sharks to absorb oxygen without having to spend energy, expending energy to produce more oxygen.
So, will sharks die if they stop swimming? The answer is not clear-cut.
While the movement is crucial for all sharks, there are a number of species that can survive and breathe by moving to the bottom of the ocean, and allowing the water to flow over their gills, providing them with the oxygen they need to survive.
However, even these species require some form of movement to stay alive.
For example, many deep-sea sharks are able to remain stationary at great depths because they live in environments where there is no light.
As a result, these animals cannot see and so cannot orient themselves. Therefore, they rely on currents to provide them with food and oxygen.
Essentially, if sharks fail to move at all, they will certainly suffer greatly.
As mentioned earlier, sharks need to remain active in order to stay alive, and when they become inactive for too long, they can begin to lose their ability to breathe.
Without continuous activity, sharks will eventually suffocate due to a lack of oxygen.
How Do Sharks Sleep?
Considering that sharks are required to continuously move, many people wonder whether they are able to sleep.
There are two main categories here – sharks who can stop swimming, and those who cannot.
In the case of the latter, these sharks are unlikely to fall into a deep sleep in the same way as humans and other creatures.
However, they may be able to rest in shallow waters, and use their fins to help keep them afloat.
In most cases, the sleep experienced by sharks is very different to that experienced by other species and creatures; one example can be seen in the metabolic rate, as sharks have a much higher metabolic rate than any other living creature.
This means that they must constantly expend large amounts of energy just to maintain their bodies, and so sleep is essential for maintaining health.
Sharks who swim through the sea usually experience a state known as ‘tonic immobility, which is similar to catalepsy.
During this period, sharks are unable to move but are still conscious. They simply cannot move due to an inability to control their muscles.
Tonic immobility is caused by the release of neurotransmitters from brain cells and is thought to be used as a defense mechanism against predators.
It is also believed that tonic immobility helps prevent sharks from being injured or killed by predators while they are sleeping.
While sharks do not appear to sleep like other organisms, they do seem to take time out to rest.
One study found that sharks were observed resting for up to 15 minutes every hour during daylight hours.
These periods of rest lasted anywhere between 10 seconds and several hours and were often followed by another bout of activity.
Sharks are fascinating creatures, and understanding how they move, breathe and sleep is an important element of gaining a more comprehensive understanding of these fascinating creatures.