Table of contents:
- The structure of the jaw
- No swim bladder
- How a shark sleeps
- Prey hunting
- Interesting facts about sharks
Video: How does a shark sleep? Features of the life and development of sharks
2024 Author: Henry Conors | [email protected]. Last modified: 2024-02-12 02:43
At the moment, about 400 species of sharks are known: from the smallest (15 cm in length) to giants (18 m in length). They have their own characteristics, but there are also common features that are inherent in almost all species:
- Sharks are not stupid animals, the ratio of their brain to body weight reaches that of some mammals.
- Life expectancy is 30 years.
- Sharks have a highly developed sense of smell and hearing, and also have an unusual sense organ - Lorenzini's electroreceptors.
- They pick up electromagnetic waves.
- Shark cartilage skeleton.
However, there are a number of features that distinguish sharks from other animals and give great mystery: for example, how a shark sleeps, how it eats, moves and hunts.
The structure of the jaw
Huge teeth 5 cm long are terrifying. On average, a predator has 4-6 rows of teeth, but some individuals can have up to 20. When the front tooth falls out, a tooth from the back row moves to replace it. By the way, losing teeth for a shark is a common thing. For 10 years, an individual tiger shark is able to change up to 24 thousand teeth. The process of change occurs with such frequencydue to the structure of the jaw: the teeth are attached directly to the gum.
No swim bladder
Unlike other fish, sharks do not have a bladder. Therefore, the animal is constantly in motion. If you stop working with your tail, the shark will sink to the bottom. Despite the absence of a bladder in all individuals, there is a species of predator that can stay afloat without additional effort. We are talking about a sand shark: it is able to swallow air and keep it in itself for several hours.
How a shark sleeps
Answering the question of how a shark sleeps, you need to understand that it does not have sleep as such. Rather, the process can be called rest. Predators living near the shore or in shallower bodies of water equip a place to "sleep" in underwater caves. There, the shark seems to be sleeping - it lies at the bottom without moving.
How do sharks sleep in the oceans? Sharks that live in deep waters almost never sleep, because, having stopped working with their tail and fins, they will dive to a great depth not intended for them. It is easier for those individuals who live at a depth all the time - they can find time for "sleep". Speaking of whether sharks sleep, you can safely give a negative answer.
Prey hunting
Sharks are very bloodthirsty. Feeling the slightest smell of blood, they immediately go to search for the victim. In hunting, a developed sense of smell helps them. It only takes 1 gram of fish blood per 1 million grams of water to feel the prey. However, if you close the nostrils of a predator, then there will be no reaction to the victim, and the shark will swim past.
When a shark has already smelled its prey, it may start to have "hungry rabies". At this moment, the predator manifests a special rage, it crushes and swallows everything in its path. In the end, the stomach, which is able to expand several times, may contain many unusual things.
As for sharks that prefer plankton and small fish, these species pass more than one hundred liters of water through themselves to feast on their favorite food. They are not dangerous to humans and are peaceful.
Interesting facts about sharks
Sharks are rather unusual creatures that you can talk about endlessly. They exist for millions of years and at the same time perfectly adapt to any living conditions. Predators have outlived the dinosaurs and are clearly not going to die out. Here are some more interesting facts about sharks:
- Baby sharks are born with teeth.
- Sharks can see colors.
- The main food of polar sharks are polar bears and deer.
- Some species can jump up to 10m high.
- To saturate the body, an animal needs 3-14% of its own body weight per week.
- There are long-lived sharks that can live up to 100 years.
Learning how sharks sleep, how they eat and how they exist, you can understand that this is a unique species of fish with a long history.
Recommended:
How do dolphins sleep? Truth and fiction about dolphin sleep
Sleep is a natural and indispensable need for all mammals on the planet. However, the truth about dolphin sleep has long been a mystery to researchers. Do dolphins really sleep with one eye open? It was once believed that these animals rest "snaps" between breaths of air or even sleep deprived at all. Both of the latter assumptions turned out to be wrong. Today, scientists already know the true answer to the question of how dolphins sleep
What does crucian eat, where does it live and what does it look like?
The king of swamps, ponds and overgrown lakes is commonly called crucian. This is a very common fish in our country. Scientists have described so far only two main types of crucians - gold (red) and silver (white), as well as one artificially bred - goldfish. From this article you will learn what crucian eats, what it looks like and where it lives
Konda: photo, nature of the channel and features of the water regime. Where does the Konda river begin and where does it flow?
One of the largest tributaries of the Irtysh, flowing within the Khanty-Mansiysk Autonomous Okrug, is the Konda River. You will find a photo, the exact location of the source and mouth, as well as detailed information about the water regime of this watercourse in our article
Polar shark. Shark habitat. reef shark
Shark is perhaps the most perfect predator of the water element, which is rightfully considered the master of the oceans. But lately, in order to satisfy his whims and various economic needs, man has been mercilessly catching and destroying these fish
The scariest shark ever. Types of sharks: description and photo
Among these marine inhabitants there are truly formidable and dangerous. Some species of sharks pose a deadly threat to unwary surfers, scuba divers and divers. Our article will tell you about the most dangerous types of sharks, descriptions and photos will help you get the most complete picture of these predatory inhabitants of the deep sea