Crocodiles - a detachment of the reptile class, distributed mainly in the southern hemisphere of the Earth. Its representatives have established themselves as ferocious and dangerous animals that leave no chance for those who meet in their path. At the same time, among crocodiles, there are modest and timid individuals who can only take small prey in the teeth. Let's learn more about these animals.
Crocodile Squad: General Description
Crocodiles are large reptiles that existed 83 million years ago. And although they are reptiles, at the genetic level they are much closer to dinosaurs and birds than to turtles or snakes.
Today, the crocodile detachment includes 23 species that belong to the family of alligator, gavial and real crocodiles. As a rule, these are powerful lizards with short and strong limbs, sharp teeth and strong jaws. The characteristic features of a detachment of crocodiles are an elongated and slightly flat body, a long tapering tail and a large head. The snout of animals also narrows at the end.
Their ears, eyes and nostrils are located in the upper part of the head, which allows animals to completely immerse themselves under water, leaving only these parts of the body above its surface. The largest species weigh up to 2 tons. But, despite this, all crocodiles swim perfectly and run fast enough. On land, they can accelerate to 17 kilometers per hour.
Traditionally, crocodiles are considered green. But in reality, the range of their color is much wider and largely depends on the specifics of the habitat. The belly of animals is usually light beige tones, but the back can be from light yellow, gray and brown, to dark green and black shades. Often in the color there are various spots and stripes. Crocodiles are truly green when they just come out of the water and the skin does not have time to dry out yet.
Variety of species
Representatives of the crocodile order are easily recognized among other reptiles, but they are often confused with each other. Distinguish predators, first of all, by the structure of the muzzle. In real crocodiles, it narrows in the form of an English V, and upper teeth are sure to peep out of the closed mouth. For alligators, the snout is more rounded and looks like the letter U, and the teeth are practically invisible. Gavials have the most striking difference, because their jaws are very narrow and long. A huge number of teeth peeping out of it, which are directed to the sides, so that it is more difficult for the extraction to free itself.
The largest in the order are combed crocodiles. Their males reach 5-7 meters in length (with tail) and weigh about 2,000 kilograms. They prefer prey of large sizes, and sometimes even attack their own kind. The second after them are Nile crocodiles living in Africa. On average, they reach 4-5 meters in length. Nile and comb species are characterized by increased aggressiveness, it is they who most often attack people.
The smallest and most timid in the squad are blunt crocodiles. Their body reaches only 1.5-2 meters in length. They are regularly attacked by more agile and larger predators, therefore they behave secretly and extremely carefully.
Habitat
Representatives of the crocodile squad live in the tropical regions of the planet. Their distant ancestors lived on land, but modern species lead a semi-aquatic lifestyle. They prefer fresh lakes, rivers or tropical swamps, where they spend most of their lives. At the same time, reptiles feel great even in bodies of water with strong salinity and are found even on the shores of the seas. Salts from the body help them remove the special glands located in the eyes and mouth. The legend about "crocodile tears" that they pour, killing prey is widely known among the people. Reptiles really "cry", but not out of pity, but from an excess of salt.
The range of crocodiles covers almost the whole of Africa, most of South America, the northeast coast of Australia and all of Oceania. They live throughout Central America and on the coast of Mexico, in the states of Florida and Louisiana (USA). In Eurasia, they are found from Pakistan to the Japanese islands.
What do they eat?
Representatives of the crocodile squad are predators. Small and medium-sized species consume fish, shellfish, crustaceans, various lizards, snakes and mice. Saltwater crocodiles, living on the Pacific coast of Australia, eat even the venomous toad aga. The diet of the Ghanaian gavial includes exclusively fish, which is why the unusual shape of its jaws is associated. In fact, the theory is not too confirmed, because his close relative, the gavial crocodile, also feeds on monkeys, otters, deer, pythons, wild pigs and other animals.
Large species of crocodiles are quite capable of coping with strong and adult prey. They hunt buffalo, livestock, zebras, antelopes, dolphins, sea turtles, sharks, birds flying over water. They do not chew food, but swallow it. Crocodiles are first torn to pieces by moving their neck from side to side.
Physiology features
The body of crocodiles is covered with a dense horny layer. It consists of dead cells, so molting is not peculiar to animals. Above, their skin is covered with round bone plates, under which various channels and cavities with nerve cells and blood vessels are located.
On land, reptiles seem slow and slow, but in water they can accelerate to 30 km / h. More than 50% of their bodies are muscles, which provide significant power. Crocodile bite is considered the strongest among all existing animals. In the largest species, it ranges from 145 to 340 atmospheres.
Crocodiles see perfectly. Their narrow vertical pupils give a viewing angle of 270 degrees, leaving blind spots in front of the muzzle and above the back of the head. Unlike other reptiles, they have good hearing. Shields on the skin perform a tactile function and are tuned to sensitivity to vibration. This helps animals navigate the water.
Lifestyle
Crocodiles spend most of their time in water. They go to land early in the morning or in the evening. They are cold-blooded, so their body temperature depends on the environment. For thermoregulation on hot days, they open their mouths so that the moisture evaporates as soon as possible.
Some reptiles live alone all year, while others calmly carry the company of relatives. Their communication with each other resembles a growl, and during the mating season turns into a real roar. When it comes time to breed, they become owners, fiercely defending their territory. Crocodiles lay eggs on the coast, burying them in the sand, silt or covering with foliage. The gender of the babies depends on the temperature of the nest. Males are hatched only at 31-32 degrees, with a deviation from this norm only females appear.