Crocodiles, the most primitive reptiles that have lived on Earth for more than 200 million years, have origins dating back to the late Triassic period. Even after two mass extinctions and constant succession of land domination, crocodiles still dominate important freshwater resources, and some crocodiles evolve in the direction of sea, land and amphibious.
Of the more than 2,000 species of reptiles that exist, there are only 23 species of crocodiles, all of which are classified as crocodilia, which is "thinner" than before. The order Crocodile is further divided into three families, namely the True Crocodile Family, the Fish-Eating Crocodile Family, and the Tuó Family. In fact, many people are stupid about what kind of crocodile belongs to and what it is called, anyway, it is called a crocodile, but there is a difference in body size.
However, if crocodiles are divided according to the killing and injury caused to humans, they can also be roughly divided into three levels: (source blogger 'Stewed Pig's Head')
Level 1 (Gangster, Don't Mess With Me): Crocodiles who kill people regularly. Representative species: Bay crocodile, Nile crocodile, Ze crocodile.
Crocodylus porosus – the largest surviving reptile in the world. Also known as saltwater crocodile, I believe everyone is very familiar with it. Males are 6–7 m long and adults weigh more than 1 tonne, while females are only 3 m long. Skill features: The bite force is 4 times that of the hyena, and it can "surf" at sea for long distances.
The Crocodylus niloticus, the most widely distributed and most adaptable crocodile in Africa, is arguably the second largest living reptile in the world. The body length is 2-6 meters, the average is 3.7 meters, and the adult weight is close to 1 ton. Skill characteristics: Hunt in groups, often preying on large herbivores such as zebras and antelopes. ps: In fact, crocodiles (Nile crocodiles) do not have a group concept, most of the time they live alone, and only cooperate in groups when hunting.
Crocodylus palustris are mainly found in densely populated south Asia, such as India, Bangladesh, Sri Lanka, Iran and southern Iraq. Its body length is 4-5 meters, and its weight does not exceed 1 ton. The skill feature is: the most flexible large crocodile on land, which can hunt deer and hares on land, and even drag prey wildly.
Studies have pointed out that crocodiles use "strategy" to prey, such as water birds during the breeding season, they will deliberately put branches on the top of their heads, wait for the male birds to collect, and then drag them into the water. PS: The 20th century was the darkest period of the Ze crocodile, about 20 million Ze crocodiles were killed, and there are about a few thousand existing ones.
All three species of crocodiles belong to the true crocodile family, and the common feature is that they all have chilling teeth, and the sharp canine teeth are interlaced with each other (large tooth), and all have a record of killing. According to data from 2008-2013, 528 attacks by saltwater crocodiles and 466 Nile crocodiles were recorded, of which more than 200 people were killed together. The record of injuries to the crocodile is relatively small (difficult to calculate), like some plantations in South Asia near the disappearance of workers from time to time, inferred that it should be the mouth of the dead crocodile, and the nearby also found the figure of the crocodile.
Second level (not active, irresponsible, not rejected): The large individual has the ability to kill but rarely kills. Representative species: American alligator, Malay crocodile.
The Alligator mississippiensis, also known as the Mikawa Crocodile (Mississippi alligator), is generally about 1.8 to 2.7 meters long, and the maximum can reach 4.5 meters long. American alligators are mostly found in Florida and Louisiana in the United States, and crocodiles are bound to be found in ponds along golf courses like Florida.
The Malay crocodile (Tomistoma schlegelii), also known as the Malay rapuncher crocodile, has an average body length of about 3 meters and is mainly distributed in the freshwater swamps, lakes and rivers of the Malay Peninsula, Kalimantan, Sumatra and Java.
Crocodiles of this level are medium-sized crocodiles, they all have the ability to kill, but they are generally not aggressive to people. Like some captive alligators, they are a bit timid and may even be scared off by domestic cats. There are now more than 1 million alligators in the United States in Florida alone, and at least 7 alligator injuries occur every year. But since 1973, there have been 23 deaths (including 8 children and 15 adults, but all occurred at the water's edge and there have been no injuries on shore). The Malay crocodile is also distributed in the southern coastal areas of China in history, and historical records record that in the Chaozhou area of Guangdong during the Tang Dynasty, fishermen working on the water and women washing by the river were attacked by Malay crocodiles.
Level 3 (Selling Cute Level): A crocodile that has no ability to kill at all. Representative species: Australian freshwater crocodile, Yangtze crocodile, pygmy crocodile.
Australian freshwater crocodile, belongs to australia's unique crocodile species, mainly distributed in the northern part of Australia freshwater rivers, lakes. Its snout is narrow, its body is relatively slender, its body length is 2-2.5 meters, and its weight is about 100 pounds. Compared with the 'Big Brother' saltwater crocodile next door, it is a small witch. However, the Australian freshwater crocodile runs fast, 25 kilometers per hour, and has a unique way of running: the front legs and hind legs move at the same time, and the front legs and hind legs move in the opposite direction.
Yangzi crocodile, another member of the genus Alligator, is a unique species in China and one of the smallest crocodile species in the world. The body length is only 1-2 meters, and the weight is about 30-36 kg. Compared with the American alligator of the same genus alligator, the Yangtze crocodile's combat effectiveness is negligible. Coupled with its sluggish movements, the Yangtze crocodile can only feed on some fish, shrimp, mollusks and insects.
Write at the end:
To this day, crocodiles remain an indispensable force in the food chain. However, for the current situation of the crocodile family, the words "hegemony falling by the side, natural enemies surrounding, and cannibalism" should be able to describe. From the time the crocodile eggs were laid to the ground, various predators of water, land and air traced, and were fortunate enough to be swallowed by large crocodiles between birth and underage, and even if they became adults, they would face various natural enemies. Adult large crocodiles rarely have natural enemies, but that doesn't mean they don't, like sharks, pythons, lions, tigers and leopards can kill it. In addition, there is one of the biggest bosses - humans...
Source: Fish Perspective
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